Steel Piston Pin Specification Example for Boat Trailers: Fixed Type
Steel Piston Pin Specification Example for Boat Trailers: Fixed Type
This is a worked specification for steel piston pin in a fixed 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 fixed type version exists because the duty cycle on boat trailers is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually premature wear on the first batch.

Example specification
| Item | Steel Piston Pin |
|---|---|
| Application | Boat Trailers |
| Version | Fixed Type |
| Base material | ABS Plastic |
| Controlled dimensions | 5 key dimensions, recorded per lot |
| Tolerance band | ±0.5 mm |
| Finish | anodised |
| MOQ | 500 pieces per specification |
| Sampling | 10 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 — ABS Plastic, 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
- CNC machining
- injection moulding
- rubber vulcanisation
- sintering
- powder coating
- cold forging
Where this example applies
Programmes that run fixed type most often specify this build for boat trailers. Related applications include fleet maintenance, municipal fleets, assembly programmes, utility trailers, light trucks.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 4.0 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
How is packing specified?
Individual packing, inner box quantity and carton marking are confirmed at quotation stage so the cartons arrive ready for your warehouse.
Do you handle mixed containers?
Yes. Most programmes consolidate several part numbers into one container to keep freight sensible at 500 pieces per line.
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.
What is the minimum order quantity?
The standard MOQ is 500 pieces per specification. Mixed sizes inside one shipment are accepted once the total reaches that figure.
Share a sample or a drawing and we will quote against a written specification, not against a photograph.



