Automotive Head Seal Specification Example for Workshop Replacements: Folding Type
Automotive Head Seal Specification Example for Workshop Replacements: Folding Type
This is a worked specification for automotive head seal in a folding type programme. It is the document we would send a buyer who asks what exactly they are getting: the material, the dimensions that are actually controlled, the finish, and the checks that happen before anything is packed.
The folding type version exists because the duty cycle on workshop replacements is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually inconsistent hardness between lots.
Example specification
| Item | Automotive Head Seal |
|---|---|
| Application | Workshop Replacements |
| Version | Folding Type |
| Base material | Reinforced Nylon |
| Controlled dimensions | 6 key dimensions, recorded per lot |
| Tolerance band | ±0.2 mm |
| Finish | painted |
| MOQ | 500 pieces per specification |
| Sampling | 7 working days, 3 days per revision |
| Compliance | SAE J431 |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Reinforced Nylon, in this example.
- List the dimensions that are actually controlled and the tolerance on each.
- Name the finish and what it has to survive.
- State the inspection level and who pays when a lot fails.
Processes involved
- die casting
- ultrasonic cleaning
- precision stamping
- laser cutting
- sintering
- powder coating
Where this example applies
Programmes that run folding type most often specify this build for workshop replacements. Related applications include aftermarket retail, municipal fleets, construction equipment, rental motorcycles, racing teams.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 2.5 sampling on the finished lot.
- Finish inspection under agreed lighting.
- Carton drop test on the first lot of a new packing specification.
Questions buyers ask
What testing is included?
Standard lots ship with dimensional and hardness reports. SAE J431 documentation is issued with the shipment when your market requires it.
Can you match an existing sample?
Send a sample and we will reverse-engineer the specification, then produce a counter sample for approval before any bulk starts.
What happens if a lot fails inspection?
The lot is re-inspected against the golden sample, and replacement pieces ship on the next available booking at our cost.
Can the specification be held on file?
Yes. Once approved, the specification is recorded against your part number so a reorder reproduces the SAE J431-compliant build instead of a fresh interpretation.
Share a sample or a drawing and we will quote against a written specification, not against a photograph.
