Automotive Head Seal Specification Example for Long-Haul Trucks: Drilled and Slotted
Automotive Head Seal Specification Example for Long-Haul Trucks: Drilled and Slotted
This is a worked specification for automotive head seal in a drilled and slotted 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 drilled and slotted version exists because the duty cycle on long-haul trucks 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 | Automotive Head Seal |
|---|---|
| Application | Long-Haul Trucks |
| Version | Drilled and Slotted |
| Base material | Forged Aluminium |
| Controlled dimensions | 5 key dimensions, recorded per lot |
| Tolerance band | ±0.05 mm |
| Finish | anodised |
| MOQ | 1,000 pieces per specification |
| Sampling | 7 working days, 5 days per revision |
| Compliance | SGS |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Forged Aluminium, 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
- rubber vulcanisation
- gravity casting
- assembly line testing
- heat treatment
- robot welding
- sintering
Where this example applies
Programmes that run drilled and slotted most often specify this build for long-haul trucks. Related applications include utility trailers, export programmes, municipal fleets, delivery vans, rental motorcycles.
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 testing is included?
Standard lots ship with dimensional and hardness reports. SGS documentation is issued with the shipment when your market requires it.
What is the minimum order quantity?
The standard MOQ is 1000 pieces per specification. Mixed sizes inside one shipment are accepted once the total reaches that figure.
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.
Can the specification be held on file?
Yes. Once approved, the specification is recorded against your part number so a reorder reproduces the SGS-compliant build instead of a fresh interpretation.
Send the part number, the annual volume and the target market, and we will come back with a specification and a sampling plan.
