Single-Cylinder Engine Specification Example for Construction Equipment: Sealed Unit
Single-Cylinder Engine Specification Example for Construction Equipment: Sealed Unit
This is a worked specification for single-cylinder engine in a sealed unit 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 sealed unit version exists because the duty cycle on construction equipment is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually premature wear on the first batch.

Example specification
| Item | Single-Cylinder Engine |
|---|---|
| Application | Construction Equipment |
| Version | Sealed Unit |
| Base material | Magnesium Alloy |
| Controlled dimensions | 6 key dimensions, recorded per lot |
| Tolerance band | ±0.2 mm |
| Finish | as machined |
| MOQ | 500 pieces per specification |
| Sampling | 14 working days, 5 days per revision |
| Compliance | ISO/TS 16949 |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Magnesium 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
- electroplating
- anodising
- rubber vulcanisation
- sintering
- cold forging
- assembly line testing
Where this example applies
Programmes that run sealed unit most often specify this build for construction equipment. Related applications include construction equipment, workshop replacements, agricultural trailers, dealership service, emergency vehicles.
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
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.
What testing is included?
Standard lots ship with dimensional and hardness reports. ISO/TS 16949 documentation is issued with the shipment when your market requires it.
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 ISO/TS 16949-compliant build instead of a fresh interpretation.
Share a sample or a drawing and we will quote against a written specification, not against a photograph.



