Manufactured in China. Assembled overseas.
An overseas equipment team planned to receive fabricated assemblies, parts and hardware from China, then complete the equipment build at its own facility.
During the quotation-stage document review, mounting features on the base frame and folded sheet-metal assemblies raised a question: did the child-part drawings also establish the relationships needed after welding?
Focus the visit on the assembly concerns
The customer clarified a focused pre-shipment inspection scope: selected assemblies, critical interfaces and temporary fit checks where possible. Full equipment assembly and functional commissioning were outside the requested work.
The planning task was to identify the objects, requirements and evidence that a limited factory visit could cover.
Three questions before preparing the check plan
- What will be delivered? The BOM included welded child parts and their completed parent assemblies.
- What must fit together? Local hole dimensions needed to be connected to the final assembly relationships.
- When can it be checked? Some requirements concerned finished geometry; other features could become inaccessible during manufacture.
From the BOM to a verifiable assembly requirement
The following teaching views show selected interfaces within the wider equipment build.
Read BOM hierarchy before counting delivery objects
In the BOM supplied for this quotation, completed weldments and their plate or tube children were listed without a clear parent–child hierarchy. Estimating the inspection scope required checking the assembly model to identify which entries belonged to one welded unit and which would be delivered separately. The comparison below illustrates the counting risk with a simplified structure.
Simplified example: all nine child pieces are welded into one base. No loose parts are included in this delivery.
Risk of direct counting
| Listed item | Qty |
|---|---|
| Base weldment | 1 |
| Longitudinal members | 2 |
| Crossmembers | 3 |
| Mounting plates | 4 |
Potential overcountIf parent and child quantities are added together
Delivery state identified
| BOM hierarchy | Qty |
|---|---|
| Base weldment | 1 |
| Longitudinal members | 2 |
| Crossmembers | 3 |
| Mounting plates | 4 |
Delivered weldmentContains nine welded child pieces
Define assembly interfaces on weldment drawings
In the reviewed package, mounting features appeared on child-part or flat-pattern drawings, while their final relationship after welding needed clarification.
A plate can have correct hole sizes and edge distances yet be positioned incorrectly within the weldment. Welding can add shrinkage or angular distortion.[1] The diagram isolates the first mechanism: the plate and its holes move together.
A check against the child dimensions would not establish the completed hole-group alignment. Without the final references and tolerances, the inspector lacks an acceptance basis for that relationship. The risk may emerge only when mating structures or brackets are assembled overseas.
Folded sheet-metal racks raise the same question: dimensions on a flat pattern describe the blank; bending and joining establish where the mounting holes sit in the completed rack.
Match machining and inspection to the final requirement
Feature purpose guides the route. A welding-fixture hole serves a different function from a locating hole used during final equipment assembly.
| Feature purpose | Manufacturing decision |
|---|---|
| Welding-process support | Prepare fixture or temporary-location features before welding, with their process requirements defined. |
| Adjustable installation | Pre-weld completion can be suitable where positional variation stays within the functional allowance—for example, a sensor bracket with sufficient adjustment range. |
| Precision location or mating | Assess post-weld finishing for critical holes and mounting faces, including any necessary stabilisation. Earlier completion needs demonstrated capability to meet the final relationship. |
For accessible final features, define the manufacturing condition, support setup and measurement method. For features that become hidden, retain traceable earlier records. Missing records require an agreed alternative check or an explicit unresolved item.
Turn the review into an agreed check plan
First reconcile the current drawings, models and approved clarifications with the factory. The full clarification history was unknown during this review; a gap in the supplied package could already have been addressed elsewhere.
Proposed interface check
- Object / requirement
- Identify the finished weldment, mating features and governing revision. Obtain the design authority’s confirmation of missing references or tolerances.
- Method / coverage
- Agree final-state measurements or a defined temporary fit check. Where mating parts are absent, record the coverage of measurements or an approved, verified gauge.
- Evidence / action
- Link results and process records to the object. Assign open questions and obtain customer disposition of deviations before the relevant release decision.
A manufacturer or inspector may flag an assembly concern; the plan should make that escalation explicit. Livenval’s proposed role is to coordinate the clarification, retain the approved decision and follow up the required evidence. The customer’s design authority confirms engineering requirements.
Make the final assembly requirement visible earlier
The useful contribution is to connect the customer’s assembly concern to the definition the factory uses and the evidence a check can provide. That gives the overseas team a clearer basis for deciding what is ready and what still needs attention.
This approach applies to welded frames, folded structures and other assemblies whose parts are made and checked separately.
Questions for your next manufacturing project
- Which assembly requirements still need agreement between your team, the manufacturer and the inspector?
- How will an approved manufacturing change reach the people responsible for inspection, final assembly and repeat orders?
- What evidence can be collected before shipment, and what must still be verified during final assembly?
About this analysis, illustrations and sources
This is a quotation-stage practice analysis. Livenval did not conduct the factory inspection; part conformity and subsequent overseas assembly results are unknown. Misalignment and assembly difficulties are discussed as risks, not recorded outcomes.
The cover shows an illustrative equipment frame. The two technical illustrations use redrawn teaching geometry, not customer production drawings. The displaced plate is deliberately exaggerated. The numerical BOM comparison illustrates a possible counting error; it is not a reported customer calculation. The check-plan extract is proposed, not a delivered report.
[1] TWI — Distortion: Types and Causes and TWI — Distortion: Prevention by Design support the discussion of welding distortion. Drawing and process recommendations here require application-specific engineering judgment and the relevant project standards.