Iron Ore Open-Pit Mine, Concentrator, Pellet Plant, Rail Terminal and Shiploader HVAC Duct Guide — Pilbara, BHP, Rio Tinto, FMG, Roy Hill, Port Hedland, Dampier, Cape Lambert

Why Australian iron ore is the largest single HVAC scope in mining infrastructure

Australian iron ore is the largest export commodity by tonnage moving across any port on the planet. The Pilbara region of Western Australia alone produces more than 800 million tonnes of iron ore annually, exported through Port Hedland (the world's largest bulk export port by tonnage, handling over 700 million tonnes per year through Pilbara Ports Authority on behalf of BHP, Fortescue Metals Group, Roy Hill, Atlas Iron and others), Dampier (Pilbara Ports Authority on behalf of Rio Tinto and others), Cape Lambert (Rio Tinto's own port), and now Onslow under construction by Mineral Resources. Beyond the Pilbara, the WA Mid-West region exports through Geraldton (Karara magnetite, the only operating Australian pelletising plant) and Esperance (Mt Gibson Koolan Island via the southern port), and the NT exports manganese (a related ore) through Groote Eylandt for South32 GEMCO. The combined HVAC duct scope across this network — from the operator cab inside a 400-tonne Liebherr T 282C haul truck at Mount Whaleback through to the shiploader baghouse on a Capesize ore carrier berth at Port Hedland — is the largest single industrial HVAC scope on the continent.

The reason that scope is so large, and so engineering-heavy, is the unique combination of constraints that the Pilbara forces on every HVAC designer. The first is climate. The Pilbara sits between 21 and 24 degrees south latitude in the heart of the arid tropical north of Australia. Summer daytime ambient temperature regularly exceeds 45 degrees C dry bulb, with peaks above 50 degrees C measured at the Newman and Tom Price weather stations, and solar gain on a haul truck cab roof under direct sun at noon adds another 15 to 25 degrees C of equivalent heat load. The HVAC cooling capacity required to hold a haul truck operator cab at 22 degrees C set point against that ambient is several times the cooling capacity of an equivalent cab operating in a temperate climate, and the filtration capacity required to keep the cab interior below the Safe Work Australia respirable inhalable dust standard of 10 mg/m³ TWA in the omnipresent Pilbara red dust is correspondingly higher than in cleaner air. Cyclone season from November through April adds tropical revolving storms (Severe Tropical Cyclone Veronica in 2019 closed Port Hedland for over a week) that test the structural integrity of every external duct fixing, every louvre, every flue stack.

The second constraint is dust. Iron ore in the bulk is hematite (Fe2O3) or magnetite (Fe3O4), and in mineral form it is not particularly hazardous. But the moment iron ore moves through a chute, a crusher, a screen, a conveyor transfer, a rail load-out, a tippler, a stacker, a reclaimer or a shiploader, mechanical reduction and abrasion generates a fine respirable fraction that contains free metallic iron from frictional contact with steel components. The fine iron dust fraction is a combustible metal dust under NFPA 660 (the consolidated combustible dust standard that absorbed NFPA 484 metal dusts in 2024), with a Kst deflagration index of 50 to 100 bar.m/s placing it in Class St-1. The dust explosion risk at every transfer point in the dry processing circuit is real — there have been documented iron dust deflagration events at international iron ore facilities, and the engineering response in modern Australian iron ore HVAC design is non-negotiable: explosion venting on every dust extract plenum to NFPA 68, explosion prevention through inerting or chemical isolation on connected enclosures to NFPA 69, spark-resistant fan construction throughout, bonded electrical continuity across all duct sections, and rigorous housekeeping protocols that prevent dust accumulation depth above the NFPA 660 0.8 mm threshold.

The third constraint is silica. Pilbara iron ore deposits sit within the Hamersley Basin and the Mara Mamba Iron Formation, with surrounding waste rock containing varying free silica fractions. Operator cab and amenity HVAC must keep respirable crystalline silica below the Safe Work Australia exposure standard of 0.05 mg/m³ TWA — recently halved from the previous 0.1 mg/m³ standard following the resurgence of silicosis cases in Australian engineered stone workers and in tunnel construction. The filtration target in the cab and amenity HVAC is correspondingly tighter than in non-silica industries. HEPA H10 was the historic minimum; H13 is increasingly specified on Tier 4 final Pilbara fleet renewals.

The fourth constraint is diesel particulate matter. Open-pit iron ore mining is one of the most diesel-intensive operations on Earth. A single Caterpillar 793F haul truck running on a Cat 3516B engine at 1,765 kilowatts at full power produces enough DPM and NOx that the dilution airflow required around the loading face and the haul road during pre-dawn loading is in the order of tens of cubic metres per second per truck. A typical Pilbara mine operates a fleet of 50 to 200 haul trucks plus 5 to 15 hydraulic excavators (Liebherr 9800, Komatsu PC4000, Caterpillar 6060), 5 to 15 wheel loaders (Caterpillar 994H, Komatsu WA1200), 20 to 50 service vehicles and 10 to 30 light vehicles. The total diesel fleet on a single Pilbara mine site can run to several hundred individual diesel sources, all needing operator cab HVAC pressurisation to keep the operator out of the cumulative exposure. The Safe Work Australia DPM exposure standard is 0.1 mg/m³ EC TWA — the same hazard class as asbestos under the IARC Group 1 carcinogen classification — and the dilution airflow required at the cab and at the workshop where these trucks are serviced is a major engineering load.

The fifth constraint is cultural heritage. Every Pilbara iron ore site sits on traditional Aboriginal land. The Banjima, Yindjibarndi, Nyiyaparli, Ngarluma, Karriyarra, Eastern Guruma, Kuruma Marthudunera and other Pilbara traditional owner groups hold native title under the Native Title Act 1993, and sacred sites are protected under the Aboriginal Heritage Act WA 1972. The Juukan Gorge incident of May 2020 — where Rio Tinto destroyed two 46,000-year-old rock shelters of cultural significance during blasting — drove a comprehensive industry rebuild of Aboriginal heritage management. Every greenfield duct routing at a Pilbara site, every new building location, every new road or trench, requires sacred site clearance through the project's Cultural Heritage Management Plan in coordination with the Native Title Holder. The HVAC designer engages early on routing rather than late on legal review, and the SBKJ engineering team in Box Hill North works with the project's Aboriginal heritage coordinator from the start of the design phase.

This guide walks an HVAC contractor, project HVAC engineer or duct fabricator from the open-pit excavator cab through to the shiploader baghouse at the export berth, with reference to the Australian standards (AS 1668.2 mechanical ventilation, AS 4254 ductwork, AS 1530.4 fire-rated, AS 3957 dust hazard, AS 1657 platforms, AS 1851 fire damper, AS 1940 flammable liquids, AS 1318 industrial chimneys, AS 3580 boundary monitoring), the limited hazardous area scope under AS/NZS 60079 (diesel refuelling, LPG storage, battery charging only), the NFPA combustible dust trilogy (NFPA 660 for the iron metal dust hazard, NFPA 68 for explosion venting, NFPA 69 for explosion prevention), the ASHRAE Applications Chapter 35 reference on industrial drying for the pellet plant, the Safe Work Australia exposure standards, the WHS Resources Mining Regulations and DMIRS WA, and the cultural heritage framework. It specifies the SBKJ machine portfolio that an Australian fabricator should be running to support an iron ore HVAC duct package from mine site through to port export.

The Australian iron ore industry context

The first fix in any iron ore HVAC scope is to understand the operator, the geography and the production scale. The Australian iron ore industry is dominated by a small number of large operators across the Pilbara region in WA, with a smaller magnetite sector in WA Mid-West and minor operations elsewhere.

BHP Iron Ore — the largest single operator

BHP Iron Ore (a division of BHP Group, ASX:BHP) operates the largest combined iron ore production in Australia at around 290 million tonnes per annum. Sites include Mount Whaleback at Newman (the original Mount Newman mine, the largest single-pit iron ore operation in the world), South Flank (commissioned 2021, the largest single greenfield iron ore project in Australia in two decades), Mining Area C, Yandi (BHP-controlled portion), Jimblebar, Mt Whaleback, Wheelarra, Caramulla, Eastern Ridge and the Newman East operations. BHP runs the BHP Iron Ore Railway from Newman through to Port Hedland, with eight-car tipplers at the port and 27,000 tonne unit trains hauling 240 wagons across the Pilbara. BHP exports through Port Hedland with multiple berths and shiploaders at the Nelson Point and Finucane Island facilities, handled by Pilbara Ports Authority.

Rio Tinto Iron Ore — diversified Pilbara portfolio

Rio Tinto Iron Ore (a division of Rio Tinto, ASX:RIO and LSE:RIO) operates approximately 320 million tonnes per annum across a diversified Pilbara portfolio. Sites include Tom Price (the original Hamersley Range mine), Paraburdoo, Brockman 2, Brockman 4, Yandicoogina, Hope Downs 1, Hope Downs 4, West Angelas, Channar, Mesa A, Mesa J, Marandoo, Western Range and Eastern Range. Rio Tinto operates its own railway network — the Pilbara Iron Ore Railway — between the mines and the ports at Dampier and Cape Lambert. Cape Lambert is Rio Tinto's own port (not Pilbara Ports Authority operated), with the largest export tonnage of any single port operator globally. The autonomous haulage system (AHS) implemented across the Rio Tinto fleet — driverless Komatsu 930E and Caterpillar 793F haul trucks operated from the Operations Centre in Perth — is among the most advanced in the world, with implications for the operator cab HVAC scope (now installed but unoccupied during routine operation, used for maintenance and emergency access only).

Fortescue Metals Group (FMG) — ASX:FMG

Fortescue Metals Group (ASX:FMG, founded by Andrew Forrest and now under a leadership team including Forrest as chairman) operates approximately 200 million tonnes per annum from the Cloudbreak, Christmas Creek, Solomon Hub (Kings, Firetail) and Iron Bridge magnetite operations. FMG runs its own railway between Cloudbreak and Port Hedland, with eight-car tipplers and multiple berths at the FMG port facility within the broader Port Hedland complex operated by Pilbara Ports Authority. Iron Bridge is FMG's higher-grade magnetite concentrate operation — a different process flow from the standard direct-shipping ore (DSO) hematite from the rest of the FMG portfolio, with concentrator and tailings infrastructure that adds substantial HVAC scope.

Roy Hill — Hancock Prospecting

Roy Hill (a Hancock Prospecting subsidiary, ultimately owned by Gina Rinehart) operates the Roy Hill mine in the Pilbara with approximately 60 million tonnes per annum capacity. The mine, the rail and the port allocation through Port Hedland is a single integrated project commissioned 2015 and now one of the larger single-site iron ore operators globally. Hancock Prospecting also owns Atlas Iron (acquired 2018) and holds a joint venture share in Karara through Karara Mining (with Sinosteel).

Mineral Resources (ASX:MIN) — Onslow Iron under construction

Mineral Resources (ASX:MIN, founded by Chris Ellison) operates several iron ore mines including Mt Webber, Iron Valley and Wonmunna with combined capacity around 20 million tonnes per annum, and is commissioning the Onslow Iron project — a new 35 million tonne per annum operation with its own dedicated port at Onslow on the WA north coast. MinRes is vertically integrated with its own crushing services subsidiary (operating processing plants on behalf of multiple mining clients including BHP and FMG), its own mining contracting services and now its own logistics chain at Onslow.

Mid-West WA and other operators

Beyond the Pilbara, smaller WA operators include Karara Mining (Karara magnetite at Geraldton — Australia's only operating pelletising plant, a joint venture between Hancock Prospecting and Sinosteel), Mt Gibson Iron (ASX:MGX — Koolan Island off the WA Kimberley coast, exported through Esperance), BCI Iron (ASX:BCI — Iron Valley and Kingston operations) and various smaller hematite producers. Champion Iron (ASX:CIA) operates Bloom Lake in Quebec Canada — not strictly Australian but ASX listed and relevant context. The WA Mid-West magnetite plays are distinct from the Pilbara hematite operations because magnetite requires concentration and pelletising before sale, whereas Pilbara hematite is direct-shipping ore that goes from mine to ship with only crushing and screening between.

Pilbara Iron Ore Bodies Association and industry bodies

The industry is represented by the WA Chamber of Minerals and Energy (CME WA), the Minerals Council of Australia (MCA), the Australian Iron and Steel Manufacturers Association (AISMA — note this is the manufacturing side), and the Iron Ore Bodies Association. The Pilbara Iron Ore industry is reported through the WA Department of Mines, Industry Regulation and Safety (DMIRS) as the regulatory body, and through the operators' quarterly production reports to the ASX. The HVAC engineering community engages with these bodies through trade events (ARBS 2026 has dedicated bulk materials handling exhibitor zones) and through the dedicated mining HVAC working groups under AIRAH and AMC.

Open-pit operations — excavator, haul truck and drill jumbo cab HVAC

The first HVAC scope at any iron ore operation is the operator cab on every diesel mobile machine. The Pilbara iron ore mining fleet operates around the clock — 24/7 shift coverage on a 12-hour roster with FIFO crews flying in and out of Perth, Karratha, Port Hedland and the airstrips at Newman, Paraburdoo, Tom Price and the operator-owned airstrips. The HVAC scope inside the cab is the operator's only protection against the cumulative shift exposure to Pilbara dust, diesel exhaust, heat and solar gain.

Haul truck operator cab — Caterpillar 793F, 797F, MT5500AC, Komatsu 930E, Liebherr T 282C

The dominant haul truck classes in Australian iron ore are the Caterpillar 793F (240 tonne class), the Caterpillar 797F (380 tonne class, used at the largest mines), the Caterpillar MT5500AC (the Cat-Atlas Copco joint venture electric drive truck), the Komatsu 930E (320 tonne class, the most numerous globally and present in large numbers at Pilbara sites), and the Liebherr T 282C (the 400 tonne class flagship operating at South Flank, Christmas Creek and Roy Hill). Each operator cab is a climate-controlled sealed cabin operating at positive pressure relative to the surrounding cab exterior. The HVAC specification is:

• Multi-stage filtration train. G4 pre-filter at the cab air inlet for the coarse Pilbara dust, F7 bag filter for the fine fraction, H10 HEPA at minimum for the respirable fraction (H13 HEPA increasingly common on Tier 4 specifications). Some sites add an activated carbon stage for diesel hydrocarbon adsorption around the loading face where exhaust concentration is highest.
• Positive pressure 50 to 100 Pa. The cab is held at positive pressure relative to the outside so that any leakage is outward and unfiltered air cannot enter the cab through small seal gaps. Pressure differential is monitored and cab pressurisation loss triggers a withdrawal condition under modern Pilbara haul truck safety specifications.
• Set point 18 to 24 degrees C. The internal set point is typically 22 degrees C dry bulb at 50 percent relative humidity, with the operator's individual preference adjustable within the 18 to 24 degree C range. The cooling capacity required to hold this against the Pilbara summer ambient — often 45 to 50 degrees C plus solar gain on the cab roof — is 10 to 18 kilowatts of refrigeration per truck.
• Redundant DX cooling. Direct expansion cooling sized for the Pilbara design ambient (often 47 degrees C plus 25 percent solar load), with redundant N+1 compressors where the operator specification supports it. Compressor failure during a shift in 45-plus degree ambient air is a withdrawal condition.
• Supply air at breathing zone. Supply registers positioned at the breathing zone level (chest to head height), return through low-level grilles to ensure that the freshest filtered air reaches the operator's nose and mouth.

The HVAC duct inside the cab is small in quantity but absolute in integrity. Typical specification is galvanised or stainless rectangular distribution duct from the air handler to the supply registers, with low leakage construction (AS 4254 class C or D, leakage below 0.1 litres per second per square metre of duct surface area at 250 Pa). The SBKJ SBAL-V auto duct production line fabricates the rectangular distribution duct at the gauge required for the cab manufacturer's specification, in galvanised standard configuration. For cab installations destined for the most aggressive marine port environments (the Cape Lambert export berth operator cabs on the shiploader trolley) the duct is upgraded to 316L stainless on the SBAL-V stainless configuration.

Hydraulic excavator cab — Liebherr R9800, Komatsu PC4000, Caterpillar 6060

The hydraulic excavator (also called the rope shovel or face shovel depending on the configuration) is the front-line loading machine at the iron ore pit face. The Liebherr R9800 at South Flank and Christmas Creek is the largest hydraulic excavator class operating in Australian iron ore, with a bucket capacity of 47 cubic metres and the ability to load a 400 tonne haul truck in 4 to 5 passes. The Komatsu PC4000 is the mid-class workhorse. The Caterpillar 6060 is the Caterpillar competitive offering. Each excavator operator cab has the same climate-controlled pressurised HVAC specification as the haul truck cab — multi-stage filtration to H10 minimum, positive pressure, 22 degree C set point, redundant DX cooling. The duct scope inside the cab is similar in size to the haul truck — small in quantity, high in integrity, SBAL-V scope at the gauge required.

Drill jumbo cab — Atlas Copco Pit Viper, Sandvik DR580

The drill jumbo at an open-pit iron ore operation drills the blast holes that fragment the ore body for excavation. The Atlas Copco Pit Viper PV-271 and PV-351 (now Epiroc branded post-spin-off) and the Sandvik DR580 are the dominant blast hole drills, with drill bits typically 311 mm or 349 mm diameter and hole depths to 50 metres. The drill operator cab has the same HVAC scope as the haul truck cab plus additional dust capture at the drill collar (where dust generation during drilling is intense) — the drill collar dust shroud connects to a local dust collector mounted on the drill itself, not part of the cab HVAC, but the cab air inlet must be located away from the drill collar dust plume to avoid overloading the cab filtration. The cab HVAC duct itself is SBKJ SBAL-V scope at the gauge required.

Wheel loader and service vehicle cabs

The wheel loader (Caterpillar 994H, Komatsu WA1200 — the largest classes in Australian iron ore) and the smaller service vehicles (graders, water trucks, fuel and lube trucks, light vehicles) have cab HVAC at progressively reduced specification — H10 HEPA on the wheel loader and graders, F7 only on the smaller light vehicles, with corresponding reductions in cooling capacity. The duct scope is small in each individual cab but multiplied across a fleet of 50 to 200 trucks plus 30 to 100 service vehicles per Pilbara mine, the total cab HVAC duct quantity per mine is substantial.

The primary gyratory crusher — the biggest single dust extract on a mine site

The primary gyratory crusher is the first reduction step at every iron ore operation. Run-of-mine (ROM) ore from the haul truck dump pocket is fed by an apron feeder into the crusher chamber, where a gyrating mantle pulverises the rock against a fixed concave liner. Typical primary gyratory dimensions are a 60 inch (1,524 mm) top size with a discharge size of 200 to 300 mm. The crusher itself is one of the largest single machines on the site — a 60-inch primary gyratory weighs several thousand tonnes installed.

Dust generation at the primary gyratory

Rock fracturing in the gyratory chamber generates respirable and inhalable dust at high intensity. Typical Pilbara primary gyratory dust release rates are 10 to 50 kilograms per hour of dust into the surrounding air at full crusher capacity. The dust is fugitive — it escapes the crusher chamber at the top opening (where the haul truck dumps the ROM ore in), at the discharge chute below (where the crushed ore drops onto the conveyor), and at any gap in the surrounding crusher building. Without dust capture, the dust loading at the crusher operator pulpit and at the crusher chamber walkway would be many multiples of the Safe Work Australia respirable inhalable dust exposure standard of 10 mg/m³ TWA.

Hood design and face velocity

Dust capture at the primary gyratory is via a hood enclosing the crusher discharge chute and the conveyor head pulley below. The hood is designed to maintain face velocity at the hood opening above the ACGIH minimum capture velocity for the dust generation type — 1.0 metres per second minimum for dust generated at low velocity, ramped to 2.5 metres per second for high-energy dust generation at chute falls. Practical Pilbara design typically targets 1.5 to 2.0 metres per second at the hood opening with the crusher operating at full capacity.

Extract duct and baghouse

Total extraction duty at a primary gyratory is 100 to 300 cubic metres per second through 1,200 to 2,000 mm round duct on the main extract. The duct routes from the hood through a network of branches, transfer ducts and main runs to a fabric filter baghouse for collection. The baghouse is sized for an air-to-cloth ratio of 0.5 to 1.0 cubic metres per minute per square metre of filter media (the iron ore industry standard for fine respirable dust capture). At a 200 cubic metre per second total extract duty, the baghouse media area is 12,000 to 24,000 square metres — a very large baghouse with multiple compartments and pulse-jet cleaning.

Duct material — heavy-gauge galvanised with abrasion lining

Duct material at the primary gyratory extract is heavy-gauge galvanised G275 1.5 to 2.0 mm wall thickness for the main runs. The high-wear elbows (the 90 degree changes of direction where dust loaded with abrasive iron ore particulate impacts the duct wall) are lined with a wear-resistant material — typically a ceramic tile (Kingfisher, ALMATIS) or a basalt brick liner, attached to the duct wall through a backing plate or a welded stud system. The lining adds 5 to 15 mm to the inside wall thickness and extends the duct service life from 2 to 4 years (unlined) to 10 to 15 years (lined) at the worst-case elbow positions.

Explosion venting and spark-resistant fan

The dust extract plenum at the baghouse and at any large duct expansion is fitted with explosion vents calculated to NFPA 68. The vent area is sized to the enclosure volume, the maximum reduced explosion pressure (Pred) for the vent panel rating, and the Kst deflagration index of the iron metal dust (typically 50 to 100 bar.m/s as the design basis). Vent panels are typically lightweight composite or thin steel with a calculated burst pressure (usually 0.05 to 0.15 bar gauge) that opens before the enclosure design pressure is reached. The fan at the baghouse outlet (the induced draft fan pulling air through the system) is specified as spark-resistant construction per AMCA Type A or Type B — typically an aluminium impeller in a steel casing with a non-sparking inlet guard, paired with a soft-start variable frequency drive that limits inrush current and inrush sparking at the motor starter.

SBKJ machinery for primary gyratory extract

The SBKJ SBTF-2020 spiral tubeformer fabricates the round main extract duct up to 2,000 mm diameter for the primary gyratory crusher. The SBTF-2020 produces round duct from 200 mm to 2,000 mm in galvanised, aluminium or stainless construction at heavy gauge, with the lock-seam pitch and the wall thickness tailored to the abrasion service. The SBAL-V auto duct production line fabricates the rectangular plenum sections at the baghouse and at any rectilinear connections to the structural plenum. The SBFB-1500 spiral fitting machine fabricates the bell-mouth inlet, the Y-piece branches, the transitions and the bell-mouth take-offs. The SBPC1500 plasma cutter cuts the heavy-gauge plate for the hood transitions and the baghouse plenum panels. The SBLR-600 inverter welder is used for field installation welding and for the periodic shutdown maintenance welding at the high-wear elbows where the abrasion lining is renewed.

Secondary cone crusher, tertiary cone crusher and HPGR

Downstream of the primary gyratory, the ore size is further reduced through secondary and tertiary cone crushers and, increasingly at modern Pilbara operations, through high pressure grinding rolls (HPGR) before entering the grinding circuit or the screening and beneficiation circuits.

Secondary cone crusher

The secondary cone crusher reduces 200 to 300 mm primary discharge to 50 to 100 mm secondary discharge. Typical secondary cone crushers at Pilbara operations are the Metso Outotec Nordberg MP series or the FLSmidth Raptor series, each rated 800 to 1,500 kilowatts and processing 1,000 to 3,000 tonnes per hour per crusher. Dust generation at the secondary crusher is similar in intensity to the primary on a per-tonne basis, but the absolute duct size is smaller because the secondary processes less tonnage per individual machine. Typical extract duty per secondary crusher is 30 to 100 cubic metres per second through 800 to 1,500 mm round duct, ducted to a shared baghouse with the primary or to a dedicated secondary baghouse depending on the plant layout.

Tertiary cone crusher

The tertiary cone crusher (if used) reduces 50 to 100 mm secondary discharge to 12 to 25 mm tertiary discharge suitable for the screening circuit or the HPGR feed. Typical tertiary crushers are smaller than the secondary, with extract duty per crusher 20 to 60 cubic metres per second through 600 to 1,000 mm round duct.

HPGR high pressure grinding rolls

HPGR is increasingly replacing the tertiary cone crusher in modern iron ore processing because of its energy efficiency advantage in the fine grinding region. The HPGR consists of two counter-rotating rolls (typically 2 to 3 metres in diameter and 1 to 2 metres wide) that compress the feed ore at pressures of 100 to 300 MPa, producing micro-cracking that enhances downstream grinding efficiency. Iron ore HPGR installations at the FMG Iron Bridge magnetite project, Karara Mining and various international magnetite operations are increasingly common. Dust generation at the HPGR is more intense than at the equivalent cone crusher because the rolls operate dry and the fine particulate generation rate is high — typical extract duty per HPGR is 50 to 150 cubic metres per second through 1,000 to 1,500 mm round duct.

Ball mill and SAG mill grinding (wet — minimal HVAC)

Ball mills and SAG (semi-autogenous grinding) mills are the primary grinding stages in magnetite concentrator operations (Karara, FMG Iron Bridge) and in any iron ore plant that requires sub-100-micron grind for downstream beneficiation. Wet grinding is the norm — water is added to the mill to form a slurry that the mill grinds and discharges to a hydrocyclone classifier. Wet grinding suppresses dust at source, so HVAC extract at the mill itself is minimal — limited to the feed and discharge end seals where slurry contact with the rotating shell can fling fine spray and droplet that contains a small respirable fraction. Typical extract duty per mill is 10 to 30 cubic metres per second through 600 to 1,000 mm round duct. Direct-shipping ore (DSO) hematite operations in the Pilbara do not typically run wet grinding — they screen and crush only, so the ball mill and SAG mill scope is concentrated in the magnetite concentrator operations.

Iron ore beneficiation — magnetic, gravity and flotation

Iron ore beneficiation upgrades the run-of-mine ore from its as-mined grade (typically 55 to 62 percent Fe for Pilbara hematite, 25 to 40 percent Fe for magnetite) to a saleable concentrate grade (typically 62 to 67 percent Fe for hematite DSO, 65 to 70 percent Fe for magnetite concentrate). Different beneficiation technologies suit different ore types.

Magnetic separation — LIMS, WHIMS, dry magnetic drums

Magnetic separation is the dominant beneficiation method for magnetite (Fe3O4) because magnetite is strongly ferromagnetic. The dominant technologies are LIMS (low-intensity magnetic separation, typically wet drum magnets at 0.05 to 0.15 Tesla), WHIMS (wet high-intensity magnetic separation, typically 0.5 to 2.0 Tesla for fine particle recovery) and dry magnetic drums for coarser feed. Wet circuits have minimal HVAC need — the operating environment is wet and the dust is suppressed at source. Dry magnetic drum circuits have hood extract at the discharge — typical duty 5 to 20 cubic metres per second per drum through 400 to 800 mm round duct.

Gravity separation — spirals, jigs, hydrocyclones

Gravity separation is the workhorse beneficiation method for hematite, taking advantage of the density difference between iron oxide (5.2 g/cm³ for hematite) and the silicate gangue (2.6 to 2.9 g/cm³). Spirals (Mineral Technologies, Multotec) and jigs (Allgaier, RC Allflux) are the dominant technologies, with hydrocyclones for classification. All of these run wet — HVAC scope is minimal at the equipment, limited to general body ventilation of the concentrator building to maintain the air-change rate and to dilute trace ammonia from the flotation reagent if used.

Flotation — Karara and CITIC Pacific magnetite

Flotation is rare for Pilbara hematite (direct-shipping ore is sold without flotation upgrade) but common for WA magnetite operations including Karara Mining and CITIC Pacific Sino Iron at Cape Preston. Flotation cells inject air into a slurry where the addition of collector and frother reagents selectively floats either the iron mineral or the gangue. The flotation circuit produces froth that overflows the cell, containing the floated mineral plus reagent residue. Reagent vapour from collectors (typically xanthate or fatty acid based for iron ore) and frothers (typically methyl isobutyl carbinol MIBC, polyglycol or pine oil) requires general body ventilation at the flotation circuit to dilute below the Safe Work Australia chemical exposure standards. Typical extract is 20 to 60 cubic metres per second of general body ventilation per flotation cell row through 600 to 1,000 mm rectangular duct. The duct is heavy-gauge galvanised with epoxy overcoat or 316L stainless depending on the reagent corrosivity.

The Karara pellet plant — induration grate-kiln-cooler

The Karara Mining pellet plant at Geraldton in Mid-West WA is the only operating iron ore pelletising facility in Australia. The plant takes magnetite concentrate from the Karara mine (a Hancock Prospecting and Sinosteel joint venture), filters it to a moisture cake, mixes with bentonite binder and any flux additives, agglomerates the filter cake in a balling drum or a balling disc to form 8 to 16 mm green balls, and indurates the green balls in a grate-kiln-cooler train at 1,300 degrees C to produce fired iron ore pellets suitable for direct charging to a blast furnace or a direct reduction shaft.

Pellet plant process flow

The Karara pellet plant operates a grate-kiln-cooler induration system (the most common configuration globally for iron ore pelletising). The grate is a moving belt that dries the green balls in successive temperature zones (UDD updraft drying, DDD downdraft drying, TPH tempered preheat, PH preheat). The rotary kiln is a 5 to 6 metre diameter rotating refractory-lined cylinder where the pellets reach the induration temperature of 1,300 degrees C — the temperature at which iron oxide grains sinter and bond, giving the pellet its strength for downstream handling. The cooler is a rotating annular cooler or a circular cooler where the indurated pellets are cooled in counter-current air flow before discharge to the product stockpile. Hot air from the cooler is recycled to the dryer and preheat zones to recover heat — a critical energy efficiency feature in modern pellet plant design.

HVAC scope at the pellet plant — four duct populations

The HVAC scope at the pellet plant divides into four distinct duct populations:

1. Combustion air supply duct. Large volume (200 to 500 cubic metres per second), ambient temperature, heavy-gauge galvanised round and rectangular construction. Feeds the kiln burner and the grate preheat burners. SBKJ scope.
2. Induration kiln flue gas extract. 1,300 degree C at the kiln discharge, cooling to 900 degree C at the preheat downstream and 400 to 600 degrees C at the recycle take-off. Refractory-lined carbon steel for the 1,300 degree C section, 310S austenitic stainless for the 600 to 900 degree C downstream section, with stack to AS 1318 industrial chimneys at the discharge. This is heavy fabrication scope, procured separately from the heat-recovery and refractory vendor (typically Outotec, Metso, Andritz, John Cockerill or Sumitomo SHI). Not SBKJ standard machinery scope.
3. Cooler exhaust recycle duct. 400 to 600 degrees C, 310S austenitic stainless duct, recycled to the dryer and preheat zones. Heat-recovery vendor scope, with the heat exchanger and the downstream HVAC duct procured separately.
4. Plant general body ventilation, control room HVAC, operator pulpit, laboratory, lab fume hood and crib room ventilation. Heavy-gauge galvanised in standard zones, 316L stainless at the laboratory fume hood and any wet processing zone. SBKJ scope.

Pellet plant control room and operator pulpit

The pellet plant control room overlooks the grate-kiln-cooler train and houses the DCS terminals, the operator workstations and the supervisory engineering office. HVAC specification is N+1 redundant cooling rated for the Geraldton ambient (typical summer 35 to 40 degrees C plus solar load), UPS-backed supply fans, low-leakage construction, smoke detection on supply air and gas-tight dampers for emergency isolation. The duct is heavy-gauge galvanised on the SBAL-V auto duct line.

Pellet plant laboratory

The pellet plant laboratory operates fume hoods for sample preparation, assay (XRF, ICP-MS, wet chemistry titration), Tumble Index testing for pellet strength, Reduction Disintegration Index (RDI) testing in a reduction tube furnace and metallurgical microscope analysis. Fume hood extraction per AS 1668.2 and the Safe Work Australia chemical exposure standards is mandatory. Duct material is 316L stainless welded construction for the corrosive sections downstream of the wet chemistry and the reduction furnace, with heavy-gauge galvanised for the upstream supply and general body ventilation. SBKJ scope — SBAL-V in 316L stainless paired with the SB-ZF1500 longitudinal stitchwelder for the welded plenum sections.

ASHRAE Applications Chapter 35 — industrial drying reference

The pellet plant induration system overlaps with ASHRAE Applications Chapter 35 (Industrial Drying) for the drying zone of the grate, where wet green balls are dried in successive temperature zones before preheat. Air flow direction, recirculation ratio, recovery of latent heat from evaporation, and the energy balance across the dryer zones are all governed by industrial drying engineering principles documented in the ASHRAE Applications handbook. The HVAC contractor working on a pellet plant scope should have this reference available alongside the standard AS suite.

Concentrate stockpile, tailings dam, and dust suppression

Downstream of the concentrator, the iron concentrate is held on a concentrate stockpile (typically in a covered shed at magnetite operations like Karara, or in an open stockpile at hematite DSO operations like the Pilbara giants), and the tailings (the gangue minerals rejected from beneficiation) are pumped to a tailings storage facility (TSF) or to a paste backfill operation.

Concentrate stockpile shed

The concentrate stockpile shed at a magnetite concentrator is a large covered building (typically 100 to 300 metres long, 30 to 60 metres wide and 20 to 40 metres high) that holds the concentrate before reclaim to the train or the ship loading sequence. The shed is enclosed to reduce wind-blown dust emission to the boundary under the AS 3580 boundary monitoring framework. Internal ventilation maintains a slight negative pressure (typically 25 to 50 Pa) relative to the outside so that any dust released during stockpile build and reclaim is captured rather than emitted to the boundary. Total ventilation duty is 50 to 200 cubic metres per second per shed through 1,000 to 1,800 mm round duct, ducted to a fabric filter baghouse and recycled to the concentrate stream so that no iron is lost. SBKJ scope — SBTF-2020 spiral tubeformer for the round duct, SBAL-V auto duct line for the baghouse plenum.

Tailings dam — minimal HVAC

The tailings storage facility is typically outdoor, with minimal HVAC scope. The tailings pumping station (which pumps the tailings slurry from the concentrator to the TSF) is a wet plant building with general body ventilation only. The TSF itself has no HVAC scope beyond any access point pumping stations.

Conveyor transfer points — the network of dust hot spots

The conveyor network at an iron ore operation links every process step, with transfer points and chutes at every direction change. Each transfer is a fugitive dust hot spot where ore falls from one conveyor onto the next, releasing dust at the chute exit, the chute throat and the receiving conveyor head. A typical mid-size Pilbara operation has 50 to 200 conveyor transfer points across the full circuit from ROM stockpile to train loadout, each requiring local dust capture.

Transfer chute design

Modern transfer chute design (the Conveyor Equipment Manufacturers Association CEMA standard and the Australian Belt Conveyor Institute reference) focuses on controlled material flow that minimises chute exit velocity, reduces material impact at the receiving conveyor and minimises dust generation. Engineered chutes with curved transfer geometry, rock boxes for terminal velocity reduction and skirtboards at the receiving conveyor are standard at modern Pilbara installations. The HVAC dust extract handles the residual airborne fraction that escapes the engineered chute despite the controlled design.

Hood extract per transfer

Each transfer point has a hood enclosing the chute exit and the receiving conveyor head, with face velocity at the hood opening above 1.5 metres per second minimum. Typical extract duty per transfer is 5 to 30 cubic metres per second through 600 to 1,000 mm round duct, ducted to a local cyclone bag filter (a small standalone baghouse mounted near the transfer) or to the central baghouse network depending on the layout. NFPA 660 housekeeping required — dust accumulation depth below 0.8 mm at all duct surfaces.

SBKJ scope at transfer points

The SBKJ SBTF-1602 and SBTF-1500C spiral tubeformer fabricate the round main duct at each transfer point in galvanised heavy gauge. The SBAL-V auto duct line fabricates the rectangular plenum sections at the local cyclone bag filter or at any rectilinear connections. The SBFB-1500 fabricates the bell-mouth inlets, the Y-piece branches and the transitions.

Rail load-out terminal — slot loading and the 27,000 tonne unit train

The rail load-out terminal at a Pilbara iron ore mine is the loading station where ore is fed from the surface stockpile onto a unit train for haulage to the port. A typical Pilbara train carries 27,000 to 30,000 tonnes of ore across 240 to 250 wagons, with each wagon holding around 110 to 120 tonnes. Loading is slot-loading from a buffer bin via a measured chute drop onto each passing wagon, with the train travelling continuously at 1 to 2 metres per second through the load-out chute. A full train load cycle takes 90 to 120 minutes from start to finish.

Slot loading mechanics

The slot loading system uses a series of measured chute drops along the load-out length, each drop sized to deposit a precise tonnage into the passing wagon as the train moves through. The chute drop distance is typically 2 to 4 metres from the chute exit to the wagon top, with ore terminal velocity of 6 to 8 metres per second by impact on the existing wagon contents. The impact energy generates fugitive dust at high intensity — a typical Pilbara load-out releases 100 to 500 kilograms per hour of airborne dust during the active loading period.

Wet dust suppression and HVAC extract

Primary dust control at the load-out chute is wet dust suppression — water sprays at the chute throat that reduce the respirable dust fraction by 60 to 90 percent before the dust leaves the chute. Secondary control is HVAC dust extract — hoods enclosing the load-out chute with face velocity at the hood opening above 2.5 metres per second to capture the residual airborne fraction not knocked down by the wet sprays. Total extraction duty at the load-out is 50 to 200 cubic metres per second through 1,000 to 1,800 mm round duct, ducted to a fabric filter baghouse.

Duct material and explosion venting

Duct material at the rail load-out is heavy-gauge galvanised G275 1.5 to 2.0 mm wall with abrasion lining at the high-wear elbows. Explosion venting on the baghouse plenum to NFPA 68. Spark-resistant fan construction. Bonded electrical continuity across all duct sections with bonding resistance below 10 ohms.

SBKJ scope at rail load-out

SBTF-2020 spiral tubeformer for the round main extract up to 2,000 mm. SBAL-V auto duct line for the rectangular baghouse plenum. SBFB-1500 for fittings. SBPC1500 for plate cutting. SBLR-600 for field welding.

The rotary car tippler — the biggest dust source at the port

The rotary car tippler at the Pilbara iron ore ports is the rail unloading station where loaded ore wagons are rotated upside down to empty their load onto a receiving conveyor below. The eight-car tandem tippler is the modern standard at BHP, FMG and Rio Tinto port facilities — eight loaded wagons are clamped into a rotary carriage and rotated 160 to 180 degrees as a single unit, dumping 8 by 110 to 120 tonnes per cycle in 2 to 3 minutes total. A typical Pilbara port handles 10 to 20 tippler cycles per hour at peak loading rate, generating airborne dust at the single largest fugitive source in any iron ore facility — 1,000 to 5,000 kilograms per hour of dust release at peak.

Tippler chamber enclosure and negative pressure

The eight-car tippler operates inside a large enclosed chamber (typically 30 to 40 metres long, 10 to 15 metres wide and 15 to 20 metres high) that contains the tippler mechanism, the wagons during inversion and the receiving conveyor below. The chamber is maintained at negative pressure relative to the outside (typically 50 to 100 Pa) so that all dust released during tipping is captured at the extract rather than escaping to the surrounding port environment. The chamber doors at the wagon inlet and outlet are interlocked with the tippler cycle to minimise the open-door time during which positive equilibration with the outside air could occur.

Extraction duct sizing

Total extraction duty at an eight-car tippler is 500 to 1,500 cubic metres per second through multiple 1,500 to 2,000 mm round main ducts, with the network feeding a large fabric filter baghouse mounted adjacent to the tippler structure. The baghouse is typically the largest single piece of HVAC equipment at the port — at a 1,000 cubic metre per second extract duty, the baghouse media area is 60,000 to 120,000 square metres across multiple compartments. The induced draft fans at the baghouse outlet are 1,500 to 3,500 kilowatts each, with redundant N+1 fan configuration so that one fan failure does not bring the tippler offline.

Duct material and combustible dust controls

Duct material is heavy-gauge galvanised G275 1.5 to 2.0 mm wall with abrasion lining at the high-wear elbows. Explosion venting on the baghouse plenum to NFPA 68 — the tippler baghouse is the largest single explosion venting calculation at the port, with vent area in the order of 50 to 200 square metres distributed across the baghouse roof and side walls. Spark-resistant fan construction throughout (AMCA Type A aluminium impeller in steel casing). Bonded electrical continuity. NFPA 660 housekeeping at intensity — the tippler baghouse is the most aggressive cleaning schedule of any HVAC equipment on the site.

SBKJ scope at the tippler

SBTF-2020 spiral tubeformer for the round main extract ducts up to 2,000 mm — this is the upper limit of the SBKJ spiral tubeformer range and the eight-car tippler scope is at the top of the SBKJ machine capacity. SBAL-V auto duct line for the rectangular baghouse plenum and the rectangular chamber wall connection ducts. SBFB-1500 for the bell-mouth inlets and the transitions at the multiple main duct headers. SBPC1500 for the heavy plate cutting at the chamber walls and the baghouse plenum. SBLR-600 for field welding during the periodic tippler shutdowns when the abrasion lining is renewed and the baghouse internals are serviced.

Stockyard, stacker and reclaimer at the port

The port stockyard at Port Hedland, Dampier and Cape Lambert holds the iron ore between rail unloading and ship loading. The stockyard is a large outdoor area (often 1 to 2 kilometres long with multiple parallel stockpiles, each holding 100,000 to 500,000 tonnes) with stacker and reclaimer machines that build and reclaim the stockpiles on a continuous cycle.

Stacker — boom stacker, slewing radial stacker

The stacker is a large rail-mounted machine that travels along the side of the stockpile, with a boom that lays down ore in a controlled pattern (typically cone-stacked or chevron-stacked depending on the blending requirement). The boom chute at the stacker tip is the main dust source — typical extract duty is 10 to 30 cubic metres per second through a small baghouse mounted on the machine.

Reclaimer — bucket wheel reclaimer, scraper reclaimer

The reclaimer is the matched machine that lifts ore from the stockpile back onto the conveyor for the next process step (typically the shiploader feed). The bucket wheel reclaimer is the dominant Pilbara configuration — a large bucket wheel mounted on a slewing boom that cuts a face into the stockpile and lifts ore onto the boom conveyor. The reclaimer generates less dust than the stacker because the bucket wheel cuts a face rather than dropping ore, but local extract is still required at the bucket wheel discharge — typical duty 5 to 20 cubic metres per second.

Operator cab on stacker reclaimer

The stacker and reclaimer operator cab is climate-controlled pressurised — the same specification as the haul truck cab but at smaller cooling capacity because the cab sits at the slewing boom counterweight position and is shielded somewhat from direct solar load. HVAC specification is multi-stage filtration to H10 minimum, positive pressure, 22 degree C set point, redundant DX cooling. Duct scope is small — SBAL-V scope at the gauge required.

Wind shield walls and boundary management

The Pilbara port stockyards operate under strict boundary air quality compliance to the WA Environmental Protection Authority — typical limit is PM10 24-hour average 50 µg/m³ and PM2.5 24-hour average 25 µg/m³ at the nearest residential boundary, with continuous monitoring under AS 3580. Wind shield walls (typically corrugated steel walls 6 to 12 metres high running along the upwind side of the stockpile) reduce wind-blown dust emission to the boundary. The HVAC scope at the stockyard is minimal beyond the operator cabs and the local extract at stacker and reclaimer tips — the boundary compliance is achieved primarily by wet dust suppression at the stockpile surface (water sprays from the gantry water cannons), wind shield walls and continuous boundary monitoring rather than by enclosed extraction.

The shiploader — loading a 200,000 DWT Capesize ore carrier

The shiploader at Port Hedland, Dampier, Cape Lambert and now Onslow is the final piece of HVAC scope before the iron ore leaves Australia. Modern Pilbara shiploaders are 10,000 to 14,000 tonne per hour rated machines that load a 200,000 to 250,000 DWT Capesize ore carrier (the standard Pilbara export vessel) through a telescopic chute that follows the rising ore level inside each hold.

Loading cycle and dust generation

A typical Capesize ore carrier has 9 to 11 cargo holds, each holding 20,000 to 25,000 tonnes when fully loaded. Loading sequence is hold-by-hold with the shiploader trolley moving between holds, the telescopic chute extending and retracting to follow the ore level, and the conveyor feed continuous from the stockyard reclaimer. Total load cycle is 18 to 30 hours per ship depending on the loader rating and the vessel size. Dust generation occurs at three points — the chute exit at the ship hold (the largest dust source, where ore impacts the existing ore pile or the steel hold floor), the chute inlet at the loader hopper (where ore transfers from the conveyor), and the conveyor head pulley at the loader.

Wet dust suppression and HVAC extract

Primary dust control at the shiploader is wet dust suppression — water sprays at the chute throat and at the chute exit that reduce respirable dust by 60 to 90 percent before the dust leaves the loader. Some operators also use fog cannons mounted on the dolphin or the loader structure that knock down airborne dust at the hold opening. Secondary control is HVAC dust extract — hoods enclosing the chute inlet and the conveyor head, ducted to a fabric filter baghouse mounted on the loader structure. Extraction duty at a 14,000 tonne per hour shiploader is 100 to 300 cubic metres per second through 1,000 to 1,800 mm round duct.

Marine environment duct material

The shiploader sits in the wet, salty marine environment of the Pilbara port. Material specification is heavy-gauge galvanised G275 1.5 to 2.0 mm wall with epoxy overcoat (typically two-pack epoxy 250 to 350 micron dry film thickness) in standard zones, upgraded to 316L stainless at the chute throat extract, at any zone with continuous water spray contact and at the marine-exposed external duct on the loader structure. The dust collected at the baghouse is recycled to the ore stream so that no iron is lost — a fabric filter blowdown system returns the collected dust to the next ore stream via a small feed conveyor.

SBKJ scope at the shiploader

SBAL-V auto duct production line in 316L stainless configuration for the corrosive marine zones, paired with the SB-ZF1500 longitudinal stitchwelder for the welded plenum sections. SBSF-1525 stainless folder for the precise heavy-gauge plate folding. SBTF-1602 and SBTF-2020 spiral tubeformer for the round main extract duct in galvanised heavy gauge with epoxy overcoat in the standard zones, and in 316L stainless at the chute throat. SBFB-1500 for fittings. SBPC1500 for plate cutting.

Heavy mobile equipment workshop and tyre fitting shed

Every Pilbara iron ore mine operates a heavy mobile equipment workshop (the "HME workshop" or "truck shop") that services the diesel fleet — haul trucks, excavators, drill jumbos, wheel loaders and service vehicles. The workshop is one of the largest single buildings on the site, typically 1,000 to 3,000 square metres in plan, 15 to 25 metres high to clear the cab of the largest haul trucks, and operating 24/7 to maintain the fleet through scheduled and unscheduled maintenance.

Heavy welding fume capture

The HME workshop generates substantial welding fume from the routine repair welding of haul truck dump bodies, excavator bucket repairs, conveyor frame repairs and structural steel work. Welding fume includes iron oxide fume (Safe Work Australia exposure standard 5 mg/m³ TWA), manganese fume from MMA and FCAW consumables (respirable Mn at 1 mg/m³ TWA), nickel and chromium fume from stainless welding (each at 1 mg/m³ TWA respirable), ozone and nitrogen oxides from GMAW and GTAW (NOx 5 ppm STEL). Local exhaust ventilation per AS 1716 and the Safe Work Australia welding fume management guidance captures the fume at source via fume arms with capture velocity above 0.5 metres per second at the welding zone, ducted to a fabric filter for collection.

Diesel exhaust capture

When haul trucks and excavators are run indoors during maintenance (engine startup checks, road testing, brake testing on the rolling road), diesel exhaust capture is required at the truck tailpipe via a flexible duct connected to the truck during the run. Diesel particulate matter exposure standard is 0.1 mg/m³ EC TWA and the capture duty per truck is 5 to 15 cubic metres per second through 200 to 400 mm flexible duct, ducted to an outside discharge or to a baghouse with diesel particulate filter.

General body ventilation and lighting

General body ventilation in the HME workshop maintains the workshop air change rate at 4 to 8 air changes per hour, dilutes residual welding fume, diesel exhaust, hydraulic oil mist and parts washer solvent vapour, and provides outdoor air to AS 1668.2 minimum standards. Heat removal from the running equipment, the welding arc heat, and the solar gain through the roof and walls is sized for the Pilbara summer ambient — typical cooling load is 200 to 500 kilowatts of refrigeration per workshop.

SBKJ machine recommendation for HME workshop

The HME workshop HVAC scope sits firmly in the SBKJ SBAL-V galvanised range for general factory ventilation. SBAL-V auto duct line for the rectangular supply and return duct in heavy-gauge galvanised G275, SBTF-1602 for the round connection ducts, SBFB-1500 for the fittings. The welding fume capture duct is on the SBTF spiral tubeformer with hood take-offs on the SBFB-1500. The diesel exhaust capture flexible duct is procured separately from a specialist supplier (Plymovent, Nederman) but the rigid connection ducts at the discharge stack and the fan plenum are on the SBAL-V.

Tyre fitting shed

The tyre fitting shed is the dedicated workshop where the giant mining tyres (4 metres tall — Bridgestone VRPS, Michelin XDR, Goodyear RM-4A+) are fitted to the haul truck wheel hubs after delivery or after recapping. The shed has heat exposure from the slow rotation of the tyre on the tyre fitting machine (which generates frictional heat at the bead seat during fitting) and requires pressurised filtered air to prevent dust ingress during the fit. HVAC specification is climate-controlled pressurised at the operator zone, with 50 to 100 Pa positive pressure, multi-stage filtration to F7 minimum, and cooling sized for the heat exposure plus the Pilbara ambient. SBKJ scope on the SBAL-V auto duct line for the rectangular distribution duct.

Mine site amenity, control room, crib room and laboratory

Every Pilbara mine site has a constellation of fixed buildings that support the operational fleet — the mine site control room, the mine site office, the crib rooms (the meal and break rooms for the shift crews), the muster point, the laboratory and assay, the first aid and emergency response building, and the heavy mobile equipment workshop. Each has its own HVAC scope.

Mine site control room

The mine site control room overlooks the open pit or sits at the central plant location depending on the layout. It houses the operator workstations for the pit production system, the autonomous haulage system (at Rio Tinto sites with AHS implementation), the SCADA terminals for the processing plant, the dispatcher workstation for the mining cycle, and the supervisory engineering offices. HVAC specification is N+1 redundant cooling rated for the Pilbara ambient (47 degree C design with solar load), UPS-backed supply fans, low-leakage construction, smoke detection on supply air and gas-tight dampers for emergency isolation. The duct is heavy-gauge galvanised on the SBAL-V auto duct line.

Mine site office and crib rooms

The mine site office and the crib rooms operate 24/7 under FIFO occupancy — typical Pilbara mine has 600 to 2,000 personnel on site at any time, rotating through 12-hour shifts on a 14-7 or 8-6 swing roster. The crib rooms in particular have heavy peak occupancy at shift changes (every 12 hours) and the HVAC sizing reflects the peak — typical 200 to 400 person crib room handles a 30-minute peak at full occupancy, with ventilation sized to maintain CO2 below 1,000 ppm at peak per AS 1668.2 default outdoor air rates. Cooling is sized for the Pilbara ambient plus internal heat gain plus the food service equipment. SBKJ scope on the SBAL-V auto duct line.

Laboratory and assay

The mine site laboratory operates fume hoods for sample preparation, assay (XRF spectrometry, ICP-MS, fire assay for gold by-product where applicable), particle size analysis (laser diffraction, sieve analysis), moisture determination and Tumble Index for product quality testing. Fume hood extraction per AS 1668.2 and the Safe Work Australia chemical exposure standards. Duct material is 316L stainless welded construction for the corrosive sections, with heavy-gauge galvanised for the upstream supply. SBKJ scope on the SBAL-V in 316L stainless paired with the SB-ZF1500 longitudinal stitchwelder.

Mine camp — refer to dedicated guide

The mine camp accommodation is a separate HVAC scope outside the operating plant and covered in detail in the SBKJ Mining Workforce Camp FIFO Village HVAC Duct Guide. Typical Pilbara camps house 400 to 4,000 FIFO workers across single-room en-suite donga units, central messes, recreation buildings, gymnasiums and the boutique services. The HVAC scope at the camp is conventional residential and commercial — galvanised duct on the SBAL-V at the gauge required.

Hazardous area scope — diesel, LPG and battery rooms

Unlike underground coal mines (where the entire mine workings are classified Zone 1 hazardous area for methane) or unlike chemical plants (where major plant zones may be Zone 1 or Zone 2), an open-pit iron ore site has limited hazardous area scope. The general body of plant air is not classified hazardous because iron oxide dust is not flammable in the conventional sense and there is no methane, hydrogen sulphide or process flammable atmosphere in the plant body.

Diesel refuelling area — Zone 1

The diesel refuelling area at every Pilbara mine site (where the haul truck and excavator fleet refuel from the on-site diesel tank farm) is classified Zone 1 hazardous area for diesel vapour under AS/NZS 60079.10.1. AS 1940 governs the flammable liquid storage. Ventilation runs at high air change rate to keep diesel vapour below the LEL, with the duct system in heavy-gauge galvanised and all in-line equipment IECEx Ex-d certified. Fire-rated duct sections per AS 1530.4 separate the refuelling station from the surrounding plant.

LPG storage — Zone 1

LPG storage (used for the haul truck cab heating, the boiler room at the camp, and occasional process applications) is classified Zone 1 under AS/NZS 60079.10.1 in the area immediately around the storage vessel and the loading point. Ventilation runs at high air change rate.

Battery charging room — Zone 2

The battery charging room (lead-acid batteries for trucks and equipment, and increasingly lithium-ion batteries as the fleet transitions) is classified Zone 2 for hydrogen released during lead-acid charging or Zone 2 for thermal runaway risk on lithium-ion. The Safe Work Australia hydrogen LEL is 4 percent by volume and the room ventilation runs at sufficient air change rate to keep hydrogen below 25 percent of LEL (1 percent absolute) at the worst-case charging load. As battery-electric mining fleet becomes more common at Australian iron ore sites in the next decade, the battery charging room HVAC scope will grow. Duct is heavy-gauge galvanised with IECEx Ex-d in-line equipment.

Explosives storage — Zone 2

The explosives magazine (storing ammonium nitrate emulsion or ANFO precursor for the blast crew) is classified Zone 2 for trace NOx and ammonia. AS 1940 and AS/NZS 60079 apply. Duct is heavy-gauge galvanised with IECEx Ex-d in-line equipment.

SBKJ machine recommendation — by iron ore application

The following machine recommendations cover the typical SBKJ portfolio for an Australian iron ore HVAC duct fabrication shop. Each application has a primary machine and one or more secondary machines for fittings, accessories and field repair.

General factory and maintenance workshop — SBAL-V galvanised

• SBAL-V auto duct production line (standard galvanised configuration) — primary machine for the general factory and maintenance workshop rectangular duct in heavy-gauge G275 galvanised steel. Covers the heavy mobile equipment workshop, the tyre fitting shed, the mine site office, the crib rooms, the mine site control room and the general plant body rectangular ventilation duct. The SBAL-V handles the 0.6 to 1.5 mm gauge range typical of the general HVAC scope.
• SBTF-1602 spiral tubeformer — secondary machine for the round connection ducts at the supply and return air handlers, the return air plenums and the general body extract main duct.
• SBFB-1500 spiral fitting machine — secondary machine for the spiral fittings (Y-pieces, bell-mouth inlets, transitions, take-offs) at the rectangular-to-round connections.

Primary gyratory crusher extract main — SBTF-2020 spiral up to 2,000 mm

• SBTF-2020 spiral tubeformer — primary machine for the round main extract duct up to 2,000 mm diameter at the primary gyratory crusher. Fabricates heavy-gauge galvanised round duct with the lock-seam pitch and the wall thickness tailored to the abrasion service.
• SBAL-V auto duct production line — primary machine for the rectangular plenum sections at the baghouse and at any rectilinear plenum connections.
• SBFB-1500 spiral fitting machine — secondary machine for the bell-mouth inlets, the Y-piece branches and the transitions at the main duct headers.
• SBPC1500 plasma cutter — secondary machine for the heavy plate cutting at the crusher hood transitions and the baghouse plenum panels.
• SBLR-600 inverter welder — secondary machine for field installation welding and for the periodic shutdown maintenance welding at the high-wear elbows.

Critical specification. Spark-resistant fan construction (AMCA Type A aluminium impeller in steel casing) and NFPA 660 housekeeping protocols are mandatory at every iron metal dust transfer point. Explosion venting on the baghouse plenum to NFPA 68 with calculated vent area sized to the enclosure volume and the worst-case iron dust Kst.

Eight-car rotary tippler extract main — SBTF-2020 at the upper limit

• SBTF-2020 spiral tubeformer — primary machine for the multiple round main extract ducts up to 2,000 mm diameter at the eight-car tippler. This is the upper limit of the SBKJ spiral tubeformer range and the tippler scope is the top of SBKJ machine capacity in iron ore.
• SBAL-V auto duct production line — primary machine for the large rectangular plenum sections at the tippler baghouse and at the rectangular chamber wall connection ducts.
• SBFB-1500 spiral fitting machine — secondary machine for the bell-mouth inlets and the transitions at the multiple main duct headers.
• SBPC1500 plasma cutter — secondary machine for the heavy plate cutting at the chamber walls and the baghouse plenum.
• SBLR-600 inverter welder — secondary machine for field welding during periodic tippler shutdowns.

Rail load-out terminal — SBTF-2020 spiral plus SBAL-V plenum

• SBTF-2020 spiral tubeformer — primary machine for the round main extract duct up to 2,000 mm at the rail load-out hood.
• SBAL-V auto duct production line — primary machine for the rectangular plenum at the load-out baghouse.
• SBFB-1500 — fittings.
• SBPC1500 — plate cutting.
• SBLR-600 — field welding.

Shiploader (316L stainless marine environment)

• SBAL-V auto duct production line (316L stainless configuration) — primary machine for the rectangular distribution duct in the corrosive marine zones at the shiploader chute throat and continuous water spray contact zones.
• SB-ZF1500 longitudinal stitchwelder — primary machine for the welded plenum sections in 316L stainless on the shiploader.
• SBSF-1525 stainless folder — primary machine for the precise heavy-gauge stainless plate folding at the chute throat fabrication.
• SBTF-1602 / SBTF-2020 spiral tubeformer — secondary machine for the round main extract duct in galvanised heavy gauge with epoxy overcoat (standard zones) and 316L stainless (chute throat and wet zones).
• SBFB-1500 — fittings.
• SBPC1500 — plate cutting.

Pellet plant control room, pulpit, laboratory (316L stainless lab + general)

• SBAL-V auto duct production line (standard galvanised configuration) — primary machine for the control room, the operator pulpit, the crib room and the general body ventilation duct.
• SBAL-V auto duct production line (316L stainless configuration) — primary machine for the laboratory fume hood ductwork.
• SB-ZF1500 longitudinal stitchwelder — secondary machine for the welded plenum sections in the laboratory stainless duct.
• SBSF-1525 stainless folder — secondary machine for the precise stainless plate folding at the laboratory fume hood throat.
• SBTF-1602 spiral tubeformer — secondary machine for the round connection ducts.

Operator cab (haul truck, excavator, drill jumbo)

• SBAL-V auto duct production line (standard galvanised configuration) — primary machine for the small rectangular distribution duct inside the cab from the air handler to the supply registers, in the gauge required by the cab manufacturer's specification.

Conveyor transfer point local extract

• SBTF-1602 / SBTF-1500C spiral tubeformer — primary machine for the round main duct at each transfer point in galvanised heavy gauge.
• SBAL-V auto duct production line — primary machine for the rectangular plenum at the local cyclone bag filter.
• SBFB-1500 — fittings.

Pilbara cyclone season, marine corrosion and field life

The Pilbara cyclone season runs from November through April, with the peak intensity typically January through March. Severe Tropical Cyclones (Category 3 and above) regularly cross the WA north coast — Veronica in 2019, Damien in 2020, Seroja in 2021 — and the bulk export ports of Port Hedland, Dampier and Cape Lambert close for typical periods of 24 to 72 hours per cyclone passage, with the most severe events closing for over a week. The HVAC design implications are several.

External structural fixings

External duct fixings must be designed for the cyclone wind loading — typical Pilbara design wind speed is 70 m/s for Category 3 cyclone (252 km/h peak gust at 10 metre height per the Australian Wind Loading Code AS 1170.2). External duct ladders, walkways, supports, louvre frames and hoods are all rated to this wind speed plus the gust factor on the local area. Routine duct hangers are sized for the static load plus the seismic factor (low in WA but still applied) and not for cyclone wind.

Marine corrosion

The Pilbara ports sit in a class C5 marine environment under AS/NZS 2312 paint specification (the most aggressive marine atmospheric class). Galvanised duct at the port has a typical field life of 5 to 10 years without epoxy overcoat, extended to 15 to 25 years with two-pack epoxy overcoat at 250 to 350 micron dry film thickness. 316L stainless duct has effectively unlimited field life in the marine environment provided the surface is kept clean of chloride deposits (which can drive crevice corrosion under deposits). The economic balance between galvanised plus epoxy overcoat and direct stainless depends on the duct location, the maintenance access cost and the operator's life cycle costing approach.

Solar radiation

Solar radiation at the Pilbara latitude (21 to 24 degrees south) is intense year-round, with solar flux at the duct surface in the order of 1,000 W/m² during midday summer. External duct surface temperature can reach 70 to 80 degrees C even with light-coloured paint, accelerating the breakdown of polymeric coatings. White or light grey epoxy overcoat is the typical specification to minimise solar absorption and surface temperature.

Aboriginal heritage, Native Title and cultural management plans

Every Pilbara iron ore site sits on traditional Aboriginal land. The Banjima, Yindjibarndi, Nyiyaparli, Ngarluma, Karriyarra, Eastern Guruma, Kuruma Marthudunera and other Pilbara traditional owner groups hold native title or registered claims under the Native Title Act 1993, and sacred sites are protected under the Aboriginal Heritage Act WA 1972.

The Juukan Gorge incident of May 2020 — where Rio Tinto destroyed two 46,000-year-old rock shelters of cultural significance at the Juukan Gorge site in the Pilbara during legal blasting at Brockman 4 — drove a comprehensive industry rebuild of Aboriginal heritage management. The Rio Tinto board resignations, the parliamentary inquiry, the Federal Government review of the Aboriginal Heritage Act WA 1972, and the operator-by-operator review of Cultural Heritage Management Plans (CHMPs) reset the engineering procurement and construction sequence for every greenfield Pilbara project.

Engineering implications for HVAC duct routing

The HVAC designer is now engaged early on duct routing — not late on legal review. Every new greenfield duct routing at a Pilbara site, every new building location, every new road or trench that the duct route requires, must have sacred site clearance through the project's CHMP in coordination with the Native Title Holder. The CHMP is developed jointly between the operator, the traditional owner representative body (Yamatji Marlpa Aboriginal Corporation YMAC for the southern Pilbara, the Pilbara Native Title Service for some groups) and the project consultants. Sacred site clearance typically takes 6 to 18 months from greenfield identification to construction approval, and any HVAC duct routing change late in the project that requires a new sacred site clearance can delay the construction window by months.

SBKJ engagement

SBKJ's engineering team in Box Hill North works with the project's Aboriginal heritage coordinator from the start of the design phase. The fabrication scope itself is delivered to the project site after sacred site clearance is complete, so the fabrication schedule is decoupled from the cultural heritage process — but the routing and the building location confirmation that drives the duct layout has to be locked in early to avoid downstream rework.

State mining regulations — DMIRS WA is the dominant jurisdiction

WA is the dominant iron ore mining jurisdiction in Australia and DMIRS (the Department of Energy, Mines, Industry Regulation and Safety) is the regulator. WA operates under the WHS (Mines) Regulations 2022 and the Mines Safety and Inspection Act 1994. The DMIRS framework includes Mine Manager appointments, Site Senior Executive responsibilities, Notifications of Significant Events, and the Major Hazard Facility registration where applicable.

Other states play smaller roles in iron ore. NSW operates under the Work Health and Safety (Mines and Petroleum Sites) Act 2013 and the WHS Mining Regulations 2014 — minor iron ore presence with operations like BCI Iron Kingston. QLD operates under the Mining and Quarrying Safety and Health Act 1999 — minimal iron ore presence. SA operates under the Mining Act 1971 — minimal iron ore. NT operates under the Mining Management Act 2001 — primarily manganese (South32 Groote Eylandt GEMCO) rather than iron ore.

The Site Senior Executive and Mine Manager

Under the WA framework, the Site Senior Executive (SSE) is the statutory role with overall responsibility for safety and health at the mine site. The Mine Manager is the statutory role responsible for the day-to-day mine operation. The HVAC duct designer and fabricator engage with the SSE's engineering team and the Mine Manager's site engineering team on the scope, the schedule and the commissioning sequence.

Safe Work Australia Workplace Exposure Standards — iron ore reference

The Safe Work Australia Workplace Exposure Standards relevant to iron ore HVAC design are:

• Respirable inhalable dust 10 mg/m³ TWA — the dominant exposure standard at iron ore sites because iron ore dust is the primary respirable contaminant.
• Respirable crystalline silica 0.05 mg/m³ TWA — recently halved from the previous 0.1 mg/m³. Pilbara iron ore dust contains silica from the surrounding waste rock and silicate gangue.
• Iron oxide fume 5 mg/m³ TWA — applies at welding fume capture in the HME workshop.
• Diesel particulate matter elemental carbon 0.1 mg/m³ EC TWA — the dominant exposure standard for the diesel fleet.
• Carbon monoxide 30 ppm TWA — applies in diesel exhaust and in the haul truck cab if pressurisation fails.
• Nitrogen dioxide 5 ppm STEL, 1 ppm TWA — applies in diesel exhaust (post-Tier 4 final still produces NOx) and in the blasting fume.
• Sulphur dioxide 2 ppm TWA — applies at the pellet plant induration kiln flue.
• Respirable manganese 1 mg/m³ TWA — applies where the ore contains manganese (South32 Groote Eylandt) and in welding fume.
• Respirable nickel 1 mg/m³ TWA — applies where the ore contains nickel and in stainless welding fume.
• Benzene-soluble fraction — applies at the haul road dust where asphalt binder breakdown products contribute.

Commissioning — fan curve, dust capture verification, NFPA 660 housekeeping baseline

Iron ore HVAC commissioning is a multi-stage process running over several months and culminating in the project HVAC engineer's sign-off as the final pre-operation acceptance milestone.

The first stage is component commissioning — fan startup against design fan curve, damper actuation testing, sensor calibration, leakage testing of installed duct sections to AS 4254 class C or D, and verification of fail-safe positions on power loss and dust alarm signal. The second stage is sub-system commissioning — primary gyratory baghouse pressure drop check, hood face velocity verification at every dust extract point, fan curve verification at the actual installed duct condition, AS 1851 fire damper test on every fire-rated penetration, baghouse explosion vent function check. The third stage is integrated system testing — coordinated response to simulated dust alarm signals from the plant SCADA, verification of withdrawal trigger response on haul truck cab pressurisation loss, validation of pressure profile and air-flow direction across the full system. The fourth stage is the NFPA 660 housekeeping baseline — initial dust accumulation depth measurement at all duct surfaces after 30 days of operation, with cleaning protocols established to maintain accumulation below 0.8 mm at all points.

The Factory Acceptance Test on first-of-type duct is the project-controlled document that ties the on-site commissioning back to the fabrication baseline. SBKJ supports witnessed FAT on first-of-type duct as standard, with full documentation including weld procedure qualification records under AS 1554.6 for stainless welding, weld inspector reports, mill certificates for raw material and dimensional inspection records for every duct section.

Project timing — typical 18 to 30 month delivery

An iron ore HVAC duct package for a typical 30 to 60 million tonne per annum greenfield Pilbara project runs 18 to 30 months from contract award to final commissioning.

• Months 0–3 — Contract award and stakeholder engagement. Detailed shop drawing development, coordination with the project HVAC engineer, the SSE engineering team, the Aboriginal heritage coordinator, the Native Title Holder representative body, the DMIRS notifications. Material specification confirmation, fire engineering basis lock-down, explosion venting calculation lock-down, NFPA 660 housekeeping protocol definition.
• Months 3–6 — First-of-type and FAT. Manufacture of first-of-type duct sections including any 316L stainless welded plenum for the laboratory, the pellet plant downstream zones and the shiploader chute throat. Factory Acceptance Test witnessed by the project HVAC engineer or the principal contractor's engineering representative. Sign-off on the welded duct assembly procedure for the stainless sections.
• Months 6–18 — Bulk fabrication. High-throughput fabrication of the bulk main and auxiliary duct on the SBAL-V auto duct line, the SBTF spiral tubeformer and the SB-ZF stitchwelder. Continuous QA witnessed at the fabricator, mill certificates collected on stainless duct, weld maps documented for fire-rated and stainless sections.
• Months 12–22 — Staged delivery. Phased delivery aligned to construction progress. Pre-strip and earthworks completion drives the early site infrastructure (office, control room, HME workshop). Crusher and processing plant construction drives the bulk dust extract duct. Rail load-out construction drives the load-out hood extract. Port works (separate from the mine but often parallel) drive the tippler, stockyard and shiploader duct.
• Months 20–26 — Installation and commissioning. Duct installation, pressure and leakage testing, fan commissioning, baghouse commissioning, explosion vent commissioning, fire damper integration test per AS 1851, NFPA 660 housekeeping baseline establishment.
• Months 26–30 — Project HVAC engineer handover. Final acceptance, as-built drawing handover, ongoing maintenance baseline established under the operator's PM system.

How SBKJ supports iron ore HVAC duct projects

SBKJ Group supplies the heavy-gauge duct fabrication machinery used by HVAC contractors and duct fabricators on Australian iron ore mining and port export projects. The relationship typically runs through one of two routes — direct supply of fabrication machinery to a contractor with in-house duct manufacturing, or supply through a fabricator partner who is bidding into the project's HVAC duct package.

Our engineering team in Box Hill North VIC supports iron ore HVAC duct projects in several ways: machine sizing for the project's specific duct material, gauge and pressure class; fabrication consultation including weld procedure development for 316L stainless sections destined for the laboratory, the pellet plant downstream zones, the shiploader chute throat and the marine environment; FAT witnessing on machinery destined for project sites; and ongoing field service support during the project's fabrication and installation phases. Our heavy-gauge machine portfolio covers round duct fabrication via the SBTF-2020 spiral tubeformer up to 2,000 mm diameter for the primary gyratory crusher extract main and the rotary tippler extract main, the SBTF-1602 and SBTF-1500C for the mid-range main and transfer point duct, rectangular duct via the SBAL-V auto duct line in heavy-gauge galvanised and 316L stainless configurations, welded duct via the SBSF-1525 stainless folder paired with the SB-ZF1500 longitudinal stitchwelder, spiral fittings via the SBFB-1500, plasma cutting via the SBPC1500 and field welding via the SBLR-600 inverter welder. Spark-resistant fan specification and NFPA 660 combustible iron metal dust housekeeping protocols are integrated into the fabrication consultation from the project award.

For HVAC contractors and duct fabricators bidding into Australian iron ore mining and port projects — whether the project sits with BHP Iron Ore at Mount Whaleback or South Flank, Rio Tinto at Tom Price or Paraburdoo or Cape Lambert, FMG at Cloudbreak or Christmas Creek or Solomon or Iron Bridge, Roy Hill in the Pilbara, Mineral Resources at Onslow Iron or Mt Webber, Karara Mining at Geraldton, Mt Gibson at Koolan Island, or through Pilbara Ports Authority at Port Hedland or Dampier — the natural starting point is a conversation about scope. Duct quantities, material breakdown across galvanised and 316L stainless, fire-rated proportion, explosion venting calculation requirement, NFPA 660 housekeeping protocol expectation, schedule and FAT requirements. From that scope we run a sizing exercise to confirm the right machine portfolio for the project. Browse the SBKJ machine portfolio or view the SBAL-V auto duct production line in detail, then go directly to contact to start the conversation. We typically reply within 12 hours from a senior engineer at the Box Hill North VIC engineering office, not a salesperson.

Related guides on SBKJ

This guide on iron ore mining and port HVAC duct sits alongside several related references on the SBKJ insights library:

• Underground mine ventilation HVAC duct guide — covers the hard rock metalliferous and coal underground operations that complement the open-pit iron ore scope, including primary fan stations, refuge chambers, bulk air coolers and the methane Zone 1 framework.
• Steel mill and smelter HVAC duct guide — covers the downstream end use of iron ore at BlueScope Port Kembla, Liberty Whyalla and the green steel transition, where the iron ore is reduced and processed into steel.
• Container port and cargo terminal HVAC duct guide — covers the broader port scope including container terminals, stevedore amenity and the port pilot operations, useful context for the bulk export terminal scope at Port Hedland, Dampier and Cape Lambert.
• Mining workforce camp FIFO village HVAC duct guide — covers the above-ground camp accommodation HVAC scope that supports the FIFO mine workforce at every Pilbara site.
• All insights articles — the full SBKJ engineering insights library.
• SBKJ machine portfolio — the full SBKJ duct fabrication machinery range.
• SBAL-V auto duct production line — the SBKJ machine used for the rectangular galvanised duct in iron ore general factory, maintenance workshop and the rectangular plenum sections at the dust extract baghouses.
• Contact SBKJ Engineering — Box Hill North VIC — direct contact with a senior engineer.

FAQ

What Australian standards and regulations apply to iron ore mine and port HVAC ductwork?

AS 1668.2 mechanical ventilation, AS 4254 ductwork, AS 1530.4 fire-rated, AS 3957 dust hazard, AS 1657 platforms, AS 1851 fire damper, AS 1940 flammable liquids, AS 1318 industrial chimneys, AS 3580 boundary monitoring. AS/NZS 60079 hazardous area classification applies only to the diesel refuelling, LPG storage and battery charging rooms — the general body of plant air is not hazardous because iron oxide is not flammable in the conventional sense, but iron metal dust is combustible under NFPA 660 with explosion venting per NFPA 68 and explosion prevention per NFPA 69. Safe Work Australia exposure standards: respirable inhalable dust 10 mg/m³, RCS 0.05 mg/m³, iron oxide fume 5 mg/m³, DPM 0.1 mg/m³ EC. State regulator is DMIRS WA for the Pilbara. Aboriginal Heritage Act WA 1972 and Native Title Act 1993 govern sacred site clearance for every Pilbara greenfield project.

Why is iron ore dust treated as a combustible metal dust under NFPA 660?

Iron ore in mineral form (hematite Fe2O3 or magnetite Fe3O4) is not combustible. But mechanical reduction and abrasion at chutes, crushers, screens and transfers generates a fine dust fraction containing free metallic iron from frictional contact with steel components. The fine iron dust is a combustible metal dust under NFPA 660 (the consolidated combustible dust standard that replaced NFPA 484 metal dusts in 2024), with Kst 50 to 100 bar.m/s placing it in Class St-1. The HVAC consequences are: explosion venting on every extract plenum to NFPA 68, explosion prevention to NFPA 69, spark-resistant fan construction (AMCA Type A aluminium impeller in steel casing), bonded electrical continuity across all duct sections (bonding resistance below 10 ohms), and NFPA 660 housekeeping protocols that keep dust accumulation depth below 0.8 mm at all duct surfaces.

What HVAC duct goes into an open-pit haul truck operator cab?

The Caterpillar 793F, 797F, MT5500AC, Komatsu 930E and Liebherr T 282C operator cabs are climate-controlled sealed cabins at positive pressure. HVAC specification: multi-stage filtration G4+F7+H10 (H13 increasingly common on Tier 4), positive pressure 50 to 100 Pa, set point 18 to 24 degrees C, redundant DX cooling sized for the Pilbara 45 to 50 degree C ambient plus solar gain. Cab pressurisation failure is a withdrawal condition. The internal duct is small in quantity but high in integrity — typically galvanised rectangular on the SBAL-V auto duct line at the gauge required by the cab manufacturer.

How is dust extracted at an iron ore primary gyratory crusher?

Dust extract at the primary gyratory is via a hood enclosing the discharge chute and the conveyor head with face velocity above 1.0 m/s minimum (ramped to 2.5 m/s for high-energy dust). Total duty 100 to 300 m³/s through 1,200 to 2,000 mm round duct, baghouse collection, explosion venting on plenum to NFPA 68, spark-resistant fan construction, abrasion lining at high-wear elbows. SBKJ SBTF-2020 fabricates round duct up to 2,000 mm and SBAL-V fabricates the rectangular baghouse plenum.

What is the HVAC scope at the Karara pellet plant induration kiln?

The Karara pellet plant at Geraldton is Australia's only operating iron ore pelletiser. HVAC scope divides into four populations: combustion air supply (heavy-gauge galvanised, large volume, SBKJ scope), induration kiln flue gas extract (refractory-lined carbon steel and 310S stainless, high temperature, separate heavy fabrication scope), cooler exhaust recycle (310S stainless, 400 to 600 degrees C, heat-recovery vendor scope) and plant general body ventilation including control room, pulpit, laboratory and crib room (SBKJ scope on the SBAL-V auto duct line in heavy-gauge galvanised plus 316L stainless for the laboratory fume hood).

How is the rail load-out terminal ventilated?

The rail load-out terminal loads a 27,000 tonne unit train via slot loading from a buffer bin. Hood extract at the chute with face velocity above 2.5 m/s, total duty 50 to 200 m³/s through 1,000 to 1,800 mm round duct, baghouse collection. Wet dust suppression at the chute throat is the primary control with HVAC extract handling the residual. Explosion venting on plenum, spark-resistant fan, abrasion lining at elbows. SBKJ SBTF-2020 for the main extract round duct and SBAL-V for the baghouse plenum.

What is a rotary car tippler and how is the dust handled?

The eight-car tandem tippler at BHP, FMG, Roy Hill and Rio Tinto ports inverts eight loaded wagons at a time in a 2 to 3 minute cycle, dumping 8 by 110 to 120 tonnes per cycle. The chamber is enclosed and held at negative pressure 50 to 100 Pa with total extract 500 to 1,500 m³/s through multiple 1,500 to 2,000 mm round main ducts to a large fabric filter baghouse. The tippler is the single largest fugitive dust source at the port (1,000 to 5,000 kg/h at peak). Explosion venting, spark-resistant fan and NFPA 660 housekeeping at intensity. SBKJ SBTF-2020 at the upper limit of its range for the main extract and SBAL-V for the baghouse plenum.

How is the Port Hedland or Cape Lambert shiploader ventilated?

A 14,000 tonne/hour shiploader loads a 200,000 DWT Capesize ore carrier through a telescopic chute that follows the rising ore level. Wet dust suppression at the chute throat is the primary control. Hood extract at the chute inlet and conveyor head, total duty 100 to 300 m³/s through 1,000 to 1,800 mm round duct, baghouse on the loader structure with dust recycled to the ore stream. Marine environment material specification — 316L stainless at chute throat and wet zones, heavy-gauge galvanised with epoxy overcoat in standard zones. SBKJ SBAL-V in 316L stainless plus SB-ZF1500 stitchwelder for the welded plenum sections, SBSF-1525 stainless folder for the chute throat fabrication.

What duct fabrication machines does SBKJ supply for iron ore projects?

The largest extract duct (primary gyratory, eight-car tippler, rail load-out and shiploader main extract up to 2,000 mm) is on the SBTF-2020 spiral tubeformer. Mid-range main duct from 200 to 1,602 mm at secondary cone crushers, HPGR rolls and transfer points is on the SBTF-1602 and SBTF-1500C. Rectangular duct for operator cabs, baghouse plenum, control room, pulpit, laboratory, mine office, crib room, HME workshop and tyre fitting shed is on the SBAL-V auto duct line (galvanised standard, 316L stainless for laboratory and marine). Welded duct for 316L stainless plenum at the laboratory, the pellet plant downstream and the shiploader chute throat is on the SBSF-1525 stainless folder paired with the SB-ZF1500 longitudinal stitchwelder. Spiral fittings on the SBFB-1500. Heavy-gauge plate plasma cutting on the SBPC1500. Field welding on the SBLR-600. Spark-resistant fan specification and NFPA 660 housekeeping are mandatory throughout.

How does Aboriginal heritage management affect iron ore HVAC duct routing?

Every Pilbara iron ore site sits on traditional Aboriginal land under the Native Title Act 1993 with sacred sites protected under the Aboriginal Heritage Act WA 1972. The Juukan Gorge incident of May 2020 drove a comprehensive industry rebuild of Aboriginal heritage management. Every greenfield duct routing, every new building location and every new trench requires sacred site clearance through the project Cultural Heritage Management Plan in coordination with the Native Title Holder (Banjima, Yindjibarndi, Nyiyaparli, Ngarluma and other Pilbara traditional owner groups). Sacred site clearance takes 6 to 18 months from greenfield identification to construction approval — the HVAC designer engages early on routing rather than late on legal review.