Phase Change Cooling System Specification Example for Passenger Cars: Lightweight Version
Phase Change Cooling System Specification Example for Passenger Cars: Lightweight Version
This is a worked specification for phase change cooling system in a lightweight 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 lightweight version version exists because the duty cycle on passenger cars is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually packing that arrived crushed at the port.

Example specification
| Item | Phase Change Cooling System |
|---|---|
| Application | Passenger Cars |
| Version | Lightweight Version |
| Base material | Cast Iron |
| Controlled dimensions | 6 key dimensions, recorded per lot |
| Tolerance band | ±0.1 mm |
| Finish | powder coated |
| MOQ | 500 pieces per specification |
| Sampling | 14 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 — Cast Iron, 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
- assembly line testing
- ultrasonic cleaning
- robot welding
- CNC machining
- precision stamping
Where this example applies
Programmes that run lightweight version most often specify this build for passenger cars. Related applications include emergency vehicles, dealership service, long-haul trucks, delivery vans, fleet maintenance.
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.
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 14 working days, and each revision round adds about 5 days once you have seen the first piece.
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.
Ask for the current catalogue and the specification sheet for this line.



