Guides
These are working documents for the people who usually decide whether a wire-and-tube seat structure gets sourced from a new plant: the buyer reading a certificate, the supplier quality engineer reading a weld report, and the design engineer deciding what the cushion frame should be made of in the first place. They are written by Wuhan Yaxin Auto Parts Co., Ltd. (武汉亚新汽车零部件有限公司), a seat frame welding shop in Wuhan, from the side that produces those documents rather than the side that files them — which is also why each one says where the document is weak, including where ours would be.
No gate, no email address required, nothing to download. If a guide answers your question and you never contact us, it did its job.
IATF 16949 "design excluded" — what it means for the part you are sourcing
What the exclusion actually excludes, which exclusions the standard permits, why certification is site-specific, and how to verify a certificate number, Unique Site Identifier and scope line independently before you send the drawing. Uses our own certificate as the worked example.
For: buyers and sourcing engineers · reading time about 12 minutes
How to read a weld penetration report for a seat frame welded assembly
What a macrograph proves and what it does not, the seven things to look for on the image, why wire-to-tube joints behave differently from the plate joints the conventions assume, the eleven fields a usable report must carry, and five ways a report can be entirely true and still worthless.
For: supplier quality engineers and welding engineers · reading time about 15 minutes
Steel wire frame or EPP frame for a seat cushion — how to choose
They are usually not alternatives: nearly every EPP cushion part still has a welded wire frame inside it. This one reframes the question as where the load path and the geometry should live, gives the eleven factors that decide it, and spends most of its length on the tolerance and datum split between the frame supplier and the foam moulder — which is where these programmes actually go wrong.
For: seat structure and design engineers, while both constructions are still on the table
Related pages that are not guides
- What we make — the three product families, the process chain, and an explicit statement of where our scope stops on a front seat.
- CNC tube bending and welded tube assemblies — the tube side of the floor: equipment, capacity against what we actually ran, and lead times.
- Quality and certification — the certificate, the equipment behind the reports, and our PPAP position stated plainly.
- How we quote — why a quotation from us is three lines and never one number.
What we are writing next
The queue is short on purpose. We would rather publish one guide that answers a question no one else has answered than six that restate what is already on the first page of a search. Two topics are in progress: what a seat frame quotation should itemise and why a single lump-sum price hides the thing you actually need to negotiate, and how sample and validation lead times are really built up on a welded assembly — where the fixture sits in that timeline, and why a wire-formed sample takes 3 working days while a welded one takes 10.
Or skip the reading
If you already know what you need made, the fastest route is the drawing itself. Send it as PDF, STEP, DWG or DXF with your annual volume and your SOP date, and within 3 working days you get back either a three-line quotation or the precise list of what we still need to know.