Industrial Timing Pulley Specification Example for City Buses: Two-Piece Construction
Industrial Timing Pulley Specification Example for City Buses: Two-Piece Construction
This is a worked specification for industrial timing pulley in a two-piece construction 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 two-piece construction 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 a supplier who changed material without saying so.
Example specification
| Item | Industrial Timing Pulley |
|---|---|
| Application | City Buses |
| Version | Two-Piece Construction |
| Base material | Aluminium Alloy |
| Controlled dimensions | 5 key dimensions, recorded per lot |
| Tolerance band | ±0.1 mm |
| Finish | anodised |
| MOQ | 200 pieces per specification |
| Sampling | 7 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 — Aluminium Alloy, 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
- electroplating
- assembly line testing
- heat treatment
- surface grinding
- precision stamping
Where this example applies
Programmes that run two-piece construction most often specify this build for city buses. Related applications include courier fleets, municipal fleets, boat trailers, agricultural trailers, aftermarket retail.
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
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 testing is included?
Standard lots ship with dimensional and hardness reports. SAE J431 documentation is issued with the shipment when your market requires it.
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.
How long does sampling take?
Samples leave the factory in 7 working days, and each revision round adds about 5 days once you have seen the first piece.
Tell us the model, the fitment and the quantity and we will hold a production slot for you.
