Aluminum Cylinder Head Specification Example for City Buses: High Performance
Aluminum Cylinder Head Specification Example for City Buses: High Performance
This is a worked specification for aluminum cylinder head in a high performance 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 high performance 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 lead time that slipped twice before bulk started.
Example specification
| Item | Aluminum Cylinder Head |
|---|---|
| Application | City Buses |
| Version | High Performance |
| Base material | PU Leather |
| Controlled dimensions | 3 key dimensions, recorded per lot |
| Tolerance band | ±0.2 mm |
| Finish | anodised |
| MOQ | 3,000 pieces per specification |
| Sampling | 10 working days, 5 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 — PU Leather, 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
- surface grinding
- rubber vulcanisation
- shot blasting
- laser cutting
- cold forging
Where this example applies
Programmes that run high performance most often specify this build for city buses. Related applications include dealership service, fleet maintenance, delivery vans, three-wheelers, assembly programmes.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 1.5 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 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.
How long does sampling take?
Samples leave the factory in 10 working days, and each revision round adds about 5 days once you have seen the first piece.
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.
Ask for the current catalogue and the specification sheet for this line.
