Table of Contents
Able Hardware builds custom welded frames to print in Suzhou, Jiangsu, about 100 km from the Port of Shanghai — welded, machined where required, finished and inspected against your drawing.
Build-to-print custom welded frames for international OEMs
Tube, plate, and machined-interface frames from prototype to production
Prototypes weld to layout lines, production runs in fixtures. Our Custom Welding & Fabrication Services keep cutting, welding, machining and finishing under one roof.
When a China OEM frame factory fits USA, EU, UK, and Australia buyers
Frames win on landed cost when they are labour-intensive and ship efficiently. A 40 ft high-cube container gives roughly 12.03 × 2.35 × 2.69 m, so nesting decides freight per frame.
Types of custom welded frames we manufacture
Welded machine frames and industrial equipment bases
Bases carrying motors, gearboxes and drive units, where mounting-plane flatness governs acceptance — see Custom Welding Frames for Industrial Machinery.
Custom tubular frames, chassis, and subframes
Square, rectangular and round sections for stands, carts, chassis and subframes, detailed under Tube Frame Welding.
Skid frames and modular equipment bases
Skids and base modules with lifting lugs, fork pockets and levelling feet, sized so the assembled unit still enters a container.
Automation, robot-cell, conveyor, and packaging-machine frames
Conveyor supports, robot pedestals and cell perimeters, where squareness and slot position drive integration hours on your floor.
Cabinet, enclosure, guard, and rack frames
Formed-panel and tube cabinets, guards and rack structures, covered by Custom Sheet Metal Frames.
Material-handling, stillage, cart, and platform frames
Stillages, kitting frames and platform bases built for repeated duty; wheeled versions appear as Industrial Trolley Carts.
Heavy-duty welded frames and post-weld machined frames
Thick-plate and structural-section frames with full-penetration joints and interfaces machined after welding.
Tubular, plate, and hybrid frame construction
Square, rectangular, and round tube frame welding
Tube delivers high stiffness per kilogram, and closed sections resist twist far better than open channels of similar mass.
Plate, structural-section, and box-section welded frames
Plate, channel and angle suit concentrated loads, bolted interfaces and impact zones, and accept heavier fillets without burn-through.
Hybrid tube-and-plate frames with gussets and machined interfaces
Most OEM frames are hybrids: tube for the load path, plate for mounting faces, gussets where bending moment peaks.
Tab-and-slot self-locating members for repeatable fit-up
Laser-cut tabs and slots locate members before tacking, cutting fixture dependence and fit-up time on low- and mid-volume frames.
Carbon steel, stainless steel, and aluminum welded frames
Q235B, Q355B, ASTM A36, and S355 carbon steel frames
Q235B and A36 sit near 235–250 MPa minimum yield; Q355B and S355 reach about 355 MPa, often allowing one wall-thickness step down.
304, 304L, and 316L stainless steel welded frames
Low-carbon 304L and 316L cap carbon near 0.030% to resist sensitisation at welds, and 316L adds molybdenum for chlorides — see Stainless Steel Welding Services.
5052, 5083, and 6061 aluminum welded frames
Aluminium at 2.70 g/cm³ against 7.85 for steel cuts mass by roughly two thirds, though 6061 softens in the heat-affected zone. Handled by our Aluminum Welding Services.
Galvanized, coated, and mixed-material frame construction
Pre-galvanized stock welds poorly and fumes, so frames destined for hot-dip galvanizing are welded bare and dipped afterwards.
Mill certificates, heat traceability, and approved grade equivalents
Q235B, A36 and S235JR are comparable, not identical. Substitutions go to you in writing before cutting, with mill certificates supplied when specified.
From tube cutting to finished and inspected frames
Laser tube cutting, plate cutting, coping, bending, and forming
Laser tube cutting produces copes, tabs, slots and holes in one setup, deleting drilling and grinding hours. Blanks are profiled through our Laser Cutting Services.
Fit-up, tack, MIG, TIG, FCAW, and robotic welding
MIG carries most carbon-steel frame volume; Custom TIG Welding Services handle thin stainless, aluminium and cosmetic seams. Full options sit under Custom Metal Welding Services.
Straightening, stress relief, and post-weld CNC machining
Long frames are checked and straightened after welding; thermal stress relief near 600 °C for carbon steel is applied before heavy machining.
Finishing, hardware install, inspection, and export packing
Coating, weld nuts, inserts and purchased hardware are fitted before final inspection, as with our OEM Welding Sheet Metal Parts.
In-house operations vs approved-partner coating and NDT
Every external handoff adds transit days and a quality interface, so we confirm the in-house split for your frame at quotation.
Frame DFM, load paths, datums, and interface design
Static load, dynamic load, fatigue, and deflection requirements
State the load case, not a weight. Fatigue depends on stress range and joint detail, so a statically safe frame can still crack at a weld toe.
Functional datums, mounting planes, and critical hole patterns
Frames need three functional datums; without them tolerances float and inspection becomes negotiation instead of measurement.
Weld access, joint size, and closed-section vent or drain review
Fillet legs beyond roughly 0.7 × the thinner member add heat and cost without strength, and closed sections need vents for coating.
Lift points, fork pockets, knock-down splits, and container-fit geometry
A bolted split can turn a low-density shipment into a stackable one, usually paying for the flanges it adds.
Drawings, STEP files, BOM, and weld maps needed for DFM review
Send 2D drawings with weld symbols, a STEP model, BOM and finish spec. Anything undefined becomes a shop-floor assumption.
Welding fixtures, manual welding, and robotic welding
Dedicated welding fixtures for repeat OEM welded frames
Fixtures, not operators, deliver repeatability. Frames over roughly 1,500 mm benefit most, since free-state distortion grows with length.
Manual vs robotic MIG welding by annual volume and joint access
Manual welding suits prototypes, evolving designs and awkward access; robotic welding pays back on stable geometry with recurring annual demand.
Fixture NRE, changeover time, and break-even quantity
Fixture NRE is quoted separately from piece price, so you can see the break-even quantity rather than absorbing tooling invisibly.
Fixture-controlled datums, locators, and free-state release checks
Locators reference drawing datums, and frames are re-measured after release — a frame in tolerance only while clamped is not in tolerance.
Post-weld machining for precision mounting interfaces
Machined pads, bores, rail seats, and hole patterns after welding
Bearing seats, rail faces and gearbox pads are cut after welding via CNC Machining & Welding Services, so datums live in the finished structure.
Common-datum machining for GD&T-controlled machine frames
Machining related features in one setup from a common datum removes stack-up between pads that must stay coplanar or parallel.
When laser-cut holes stay as-welded vs when they must be remachined
Clearance holes for brackets and covers stay as-cut; dowel holes, bearing bores and rail-locating features are machined afterwards.
CMM, portable-arm, and laser-tracker inspection of large frames
Small frames go to a CMM; frames beyond CMM travel are measured with portable arms or laser trackers against the same datum scheme.
Weld quality, NDT, dimensional inspection, and traceability
WPS, PQR, and ISO 9606 or AWS D1.1 welder qualification
When a code is contractually invoked, procedures and welder qualifications are established to that standard before production, with scope agreed at technical review.
ISO 5817 weld quality levels and 100% visual inspection
ISO 5817 levels B, C and D define acceptance objectively. Specify a level per joint class instead of asking for “good welds”; every frame is visually inspected.
PT, MT, UT, or RT on critical frame joints when specified
Penetrant, magnetic particle, ultrasonic or radiographic testing follows the drawing at an agreed sampling level, typically on lifting points and full-penetration joints.
FAI, weld maps, mill certificates, and export documentation packs
New and revised frames receive a dimensioned first-article report with measured values, backed by our Quality Control system.
ISO 3834, EN 1090, and customer standards by contract scope
ISO 3834 covers fusion-welding quality requirements and EN 1090 applies to structural steel and aluminium sold into the EU. Confirm scope early, as it changes documentation and cost.
Powder coating, painting, galvanizing, and passivation
ISO 12944 coating systems for indoor, outdoor, and coastal frames
ISO 12944 grades environments from C1 indoors to C5 and CX in coastal service; naming the category stops an indoor system reaching a marine site.
Powder coat, wet paint, e-coat, and zinc plating options
Powder coating around 60–80 µm covers most sheltered frames, wet paint suits very large frames and touch-up, and plating suits hardware. Options sit under Metal Surface Treatment.
Hot-dip galvanizing vent, drain, bath size, and distortion limits
Closed sections need vent and drain holes, the frame must fit the bath, and immersion near 450 °C can distort slender members.
Passivation and pickle finishes for stainless welded frames
Weld heat tint is removed to restore corrosion resistance, followed by pickling and passivation, with graining or blasting where appearance matters.
Masking machined pads, threads, dowels, and grounding points
Coating adds thickness, so machined pads, tapped holes, dowels and earth points are masked to protect assembly fit and electrical bonding.
How to evaluate a welded frame manufacturer in China
Envelope, fixture, metrology, and finishing capability checks
The smallest limit governs your frame: laser bed, tube length, brake tonnage, fixture table, crane capacity, machining travel, coating booth and galvanizing bath.
Sample quality, NCR handling, and third-party inspection
Request a sample report with measured values and one anonymised nonconformance showing corrective action, and confirm you may appoint SGS, Bureau Veritas or your own inspector.
Supplier scorecard for engineers, SQEs, and procurement
Score DFM response quality, on-time first-article delivery, dimensional yield and documentation completeness — not piece price alone.
Drawing confidentiality, NDAs, and tooling ownership
Sign an NDA before sending files, and state in the purchase order who owns fixtures and tooling once NRE is paid.
Custom welded frame FAQs
What files are required to quote a custom welded frame?
A 2D drawing with weld symbols and tolerances, a STEP model, BOM, finish specification, and prototype plus annual quantities. Samples can be reverse-engineered into drawings for approval.
What tolerances can a custom welded frame hold?
Welded structures are toleranced to ISO 13920 classes, while machined features use ISO 2768 or explicit GD&T. Applying machining tolerances to as-welded features creates disputes no shop can win.
When should mounting surfaces be machined after welding?
Whenever flatness, parallelism, bore alignment or hole position must hold tighter than welding distortion allows — typically bearing seats, rail faces and gearbox interfaces.
What is the typical prototype and production lead time from China?
Lead time follows material availability, fixture build, coating queue and inspection scope, so we confirm dated milestones per project rather than a blanket figure.
Request a custom welded frame quote
Send drawings, STEP files, BOM, finish specification and quantities, with destination port and preferred Incoterm — FOB, CIF or DDP — so the quotation reflects landed cost. Our engineers return manufacturability feedback and cost drivers with the price. Contact Able Hardware in Suzhou to start your custom welded frame project.