Subcontracted EXC3 fabrication without welding coordination
A steelwork contractor is awarded a contract for a two-storey steel frame to EN 1090-2, execution class EXC3. The contractor holds EN 1090-1 FPC certification and has a welding coordinator (IWE). The contractor plans to subcontract the shop welding of the primary moment frames to a small workshop that has no EN ISO 3834 certification and no qualified welding coordinator, but claims its welders are 'certified' by a local training school. The subcontractor will use the main contractor's WPSs and WPQRs. The client's engineer asks for the Declaration of Performance and the FPC certificate before delivery. During a visit, the main contractor's QA manager finds that the subcontractor has not calibrated its welding machine for 18 months and that the WPQ certificates for two welders are for fillet welds only, although the production includes full-penetration butt welds. The main contractor wants to proceed because the delivery date is fixed.
1. Identify the nonconformities and explain the main contractor's responsibilities for subcontracted work under EN 1090-2 and EN 1090-1.
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The nonconformities are: the subcontractor has no EN ISO 3834 certification and no qualified welding coordinator; the welders are qualified only for fillet welds but will make full-penetration butt welds; and the welding machine has not been calibrated for 18 months. Under EN 1090-2 for EXC3, the manufacturer must operate a factory production control system according to EN 1090-1 and must have welding coordination. Subcontracting is permitted, but the main contractor remains responsible for the subcontracted work. The subcontractor must work within the main contractor's FPC system, and its welding coordination must be under the main contractor's responsible welding coordinator. The main contractor cannot simply lend its WPSs and WPQRs and assume the work is compliant. The Declaration of Performance is a legal document under the Construction Products Regulation; the main contractor cannot issue it if the frame is not manufactured under the certified FPC. The delivery date is not a justification for bypassing these requirements.
2. What actions must be taken before the subcontracted work can be accepted, and what are the contractual risks if the frame is delivered as it is?
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Before acceptance, stop production and correct the nonconformities. Calibrate the welding machine and record the calibration. Qualify the welders to ISO 9606-1 for full-penetration butt welds in the required position and thickness; fillet-only certificates are not valid. Audit the subcontractor against the main contractor's FPC and place the work under the main contractor's welding coordinator. Confirm that the WPSs and WPQRs are applicable to the subcontractor's equipment and conditions, or qualify new procedures. Notify the client's engineer and provide the corrected records. If the frame is delivered as it is, the CE marking and Declaration of Performance would be unsupported, the client could reject the frame, and the main contractor could face contractual liability, loss of certification and market-surveillance action. The fixed delivery date does not transfer the legal responsibility to the client.
3. How should welding coordination and welder qualification be handled in this subcontract?
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The main contractor's IWE should remain the responsible welding coordinator for the project. The subcontractor may appoint a welding coordinator under him, but that person must have the competence required for EXC3, and the responsibility cannot be left with an unqualified person. The subcontractor's welders must hold valid ISO 9606-1 qualifications for the joint type, process, position, thickness and backing condition used in production. The certificates should be checked for validity, issuing body and scope. The main contractor should keep a register of welders and qualifications and verify that each welder works within the qualified range. The WPSs and WPQRs can be used by the subcontractor only if the main contractor's coordinator confirms that the subcontractor's equipment and conditions are covered. If not, new procedure qualification is required. All records should be available for the client and for the FPC audit.