Inside the SBKJ Jiangyin factory

Where the factory sits and why it matters

The SBKJ factory is in Jiangyin, Jiangsu Province — one of the densest steel and machinery clusters in eastern China. Jiangyin sits between Shanghai and Nanjing on the south bank of the Yangtze River, ninety minutes by car from Shanghai Hongqiao international airport and sixty minutes from Wuxi Sunan Shuofang airport. Two things matter about that location for buyers. First, the supplier base for galvanised steel coil, hydraulic valves, gearmotors, PLCs, frequency drives and structural steel is concentrated within a hundred kilometres of the workshop — SBKJ does not need to truck in critical components from across the country, which keeps lead times predictable and allows the QA team to visit suppliers in person when an issue surfaces. Second, the port of Shanghai is a four-hour road haul from the factory gate, so finished machines reach the container yard and the export terminal in a single day — faster and more reliable than factories in inland provinces that need a multi-day rail haul to reach blue water.

How the workshop is laid out — one continuous flow

The Jiangyin facility runs three connected production halls. The first hall handles incoming steel: coil storage, sheet shearing, plasma and laser cutting, structural steel preparation and welding. The second hall is the machining and sub-assembly area, where forming heads, fold stations, cassette holders, decoiler bodies, hydraulic units and electrical cabinets are built up as discrete sub-assemblies before they reach the main line. The third hall is the integration and test bay, where the sub-assemblies are bolted together into the finished machine, the electrical cabinet is married to the mechanical structure, the PLC is loaded, and the machine runs its first powered cycle. The layout is deliberately one-directional: a machine enters the first hall as raw material and never doubles back, which keeps work-in-progress visible and makes scheduling far easier than the back-and-forth flow common in older Chinese workshops.

The five workshop stations every machine passes through

SBKJ production is organised around five named stations. Each one has a fixed location, dedicated tooling, a responsible foreman, and a sign-off step before work moves on. None of the five can be skipped.

1. Structural steel preparation and welding

This is where the machine's skeleton is built. Heavy-gauge structural steel is shot-blasted, cut to length, drilled and welded into the base frame of the line. Welders use jigs to lock alignment so that the long base rails of an SBAL-V auto duct line stay straight to within a small fraction of a millimetre over the full machine length — alignment that the buyer never sees but that determines whether a finished duct comes off the line square or twisted. After welding, the frame is stress-relieved, primer-coated and inspected against the drawing before it leaves the bay.

2. Machined surface preparation and sub-assembly

Forming rollers, fold heads, cassette holders, drive shafts, gearbox mounts and pneumatic cylinder brackets are all built as discrete sub-assemblies in the second hall. Critical surfaces are CNC-machined to drawing tolerance, then fitted, lubricated and bench-tested before being released to the main line. Sub-assemblies that fail bench inspection are reworked or scrapped at this stage rather than discovered later when they are buried inside a half-built machine. This is one of the most important quality steps in the workshop because it catches defects when they are still cheap to fix.

3. Electrical cabinet build

SBKJ builds its own electrical cabinets in-house. The cabinet bay holds the inventory of branded electrical components — Schneider, Siemens, Mitsubishi, Omron, Delta and other major-brand contactors, drives, PLCs and HMIs as the project specification calls for — and a panel-build station where the wiring loom, terminal blocks, cable trays and component mounting are completed against the schematic. Every cabinet is point-to-point continuity tested before it leaves the bay. This in-house build is why SBKJ can guarantee genuine branded electrical components on every machine: the cabinet is never sub-contracted to an outside panel shop.

4. Final integration and powered run-up

The integration bay is where the structural frame, the sub-assemblies and the electrical cabinet come together. The mechanical assembly is completed first — rollers, drives, hydraulic and pneumatic plumbing, guarding, sensors. Then the electrical cabinet is craned into position and the wiring loom is connected to the field devices. The machine is then energised for the first time, the PLC program is loaded from a checksummed master copy, and the integration team runs a no-load motion sequence to verify that every axis moves in the right direction and every sensor reads correctly. Only when the no-load run is clean does the machine move to the test bay.

5. Test bay and FAT preparation

The dedicated test bay is the last station in the workshop. Here the machine runs the full forming program at no-load and at full design load using SBKJ stock galvanised coil. Cycle times, motor currents, hydraulic pressures, seam quality and dimensional accuracy are all measured and recorded. When the test bay is satisfied, the machine is cleaned, touched-up, photographed for the build record, and made ready for the buyer's factory acceptance test (FAT). The FAT itself is run in the same bay, against the buyer's nominated coil and target program, with the buyer's authorised engineer present.

Production capability — what the factory can actually deliver

Capacity is not a single number because SBKJ runs a mixed-output workshop. High-volume product families — TDF flange machines, lockformers, beading and grooving machines — can be built in batches of ten or more in parallel because they share tooling and electrical cabinets. Lower-volume, higher-complexity lines — SBAL-V auto duct, SBEM rectangular duct line, SBTF-1602 and SBTF-2020 spiral tubeformers — are built one or two at a time because they need dedicated bay space and longer test cycles. The factory is sized to deliver several full SBAL-V lines per quarter alongside continuous production of the higher-volume product families. SBKJ Group has shipped 5,000+ machines to 80+ countries since 1995, and the production schedule is published quarterly so the sales team can give buyers a realistic delivery date at the moment of order confirmation rather than a marketing promise.

Export packing and dispatch — getting the machine to your port

Export packing is its own discipline at SBKJ and is handled by a dedicated packing team in the dispatch bay at the back of the workshop. Every machine is shrink-wrapped, foam-padded around fragile assemblies, bolted to a custom-built timber base, and either crated or loaded directly into a container depending on the destination. Containers are stuffed at the factory under SBKJ supervision, sealed, and trucked to Shanghai port. The shipping documentation pack — commercial invoice, packing list, bill of lading, fumigation certificate where required, certificate of origin, and the machine document pack inside the electrical cabinet — is prepared by the SBKJ export team and sent to the buyer's freight forwarder. SBKJ has shipped to 80+ countries and knows the documentation quirks of the major destination markets, including LC-payment-driven jurisdictions in the GCC and Southeast Asia, AS/NZS-stamped paperwork for Australia and New Zealand, and EU CE conformity files for European buyers.

Visiting the factory — what to know before you travel

SBKJ welcomes buyer visits at every stage of the project — pre-order to walk the workshop and see machines being built, mid-build to see your specific machine on the assembly bay, or for the FAT to sign off the completed line. Most visits are scheduled to coincide with the FAT because it is the most informative use of the buyer's travel budget: you see your own machine running on your own coil, you sign the FAT report, and you meet the SBKJ engineer who will travel for commissioning. SBKJ can arrange airport pick-up from Shanghai Hongqiao or Wuxi Sunan Shuofang, a hotel near the factory, an interpreter, and meeting space inside the workshop. Visa support letters are issued on request. The best months for visits are March–June and September–November — the Jiangyin summer (July–August) is hot and humid, and the workshop is significantly more comfortable in spring and autumn.

Frequently asked questions

Where is the SBKJ factory located?

The SBKJ Group manufacturing facility is in Jiangyin, Jiangsu Province, China — about 90 minutes by car from Shanghai Hongqiao airport and 60 minutes from Wuxi Sunan Shuofang airport. The factory has produced HVAC ductwork machinery on this site since 1995.

How big is the SBKJ factory?

The Jiangyin facility runs three connected production halls covering structural steel fabrication, machine assembly, and a dedicated test bay. The footprint supports parallel build of multiple full duct lines, including the SBAL-V auto duct line and the SBTF-2020 spiral tubeformer.

How many machines does SBKJ produce per year?

SBKJ Group has shipped 5,000+ machines to 80+ countries since 1995. Annual output varies by mix — the factory can deliver high-volume runs of TDF flange and lockformer machines alongside the lower-volume, higher-complexity SBAL-V and SBTF-2020 lines.

Can I visit the SBKJ factory in person?

Yes — SBKJ welcomes buyer visits at any stage of the project. Most visits are scheduled to coincide with the FAT (factory acceptance test) so you can see your machine running on your nominated coil. SBKJ can arrange airport pick-up from Shanghai Hongqiao or Wuxi Sunan Shuofang and a hotel near the factory.

What documents come with the machine when it ships?

Every machine ships with a sealed document pack containing the FAT report, CE Declaration of Conformity (where applicable), ISO 9001 certificate copy, operator manual, electrical schematic, hydraulic and pneumatic schematic where applicable, spare parts list, lubrication chart and warranty card.

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