Hydraulic Piston Specification Example for City Buses: All-Weather Version
Hydraulic Piston Specification Example for City Buses: All-Weather Version
This is a worked specification for hydraulic piston in a all-weather version 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 all-weather version version exists because the duty cycle on city buses is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually documentation that arrived after the container shipped.

Example specification
| Item | Hydraulic Piston |
|---|---|
| Application | City Buses |
| Version | All-Weather Version |
| Base material | ABS Plastic |
| Controlled dimensions | 5 key dimensions, recorded per lot |
| Tolerance band | ±0.05 mm |
| Finish | anodised |
| MOQ | 500 pieces per specification |
| Sampling | 14 working days, 3 days per revision |
| Compliance | ECE R90 |
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
- gravity casting
- ultrasonic cleaning
- laser cutting
- die casting
- powder coating
- assembly line testing
Where this example applies
Programmes that run all-weather version most often specify this build for city buses. Related applications include rental motorcycles, delivery vans, long-haul trucks, utility trailers, trailer axles.
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
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.
Can the specification be held on file?
Yes. Once approved, the specification is recorded against your part number so a reorder reproduces the ECE R90-compliant build instead of a fresh interpretation.
How long does sampling take?
Samples leave the factory in 14 working days, and each revision round adds about 3 days once you have seen the first piece.
What testing is included?
Standard lots ship with dimensional and hardness reports. ECE R90 documentation is issued with the shipment when your market requires it.
Send the part number, the annual volume and the target market, and we will come back with a specification and a sampling plan.



