Posted By Phil Atkinson Can anybody offer some advice on what I should be looking for in terms of qualifications for a welder to repair pipework that carries liquid under a pressure of about 3 Bar? All advice is very much appreciated.

Posted By Roger the Dodger Suggest you need to complete the usual risk assessment. Are you welding on the pipeline directly or just near to it? Whats in the pipeline? Something flammable and all the qualifications in the world won't stop it going bang. Can the pipeline be de-pressurised/vented, drained off and isolated. You need to develop a safe system of work. As regards welders qualification is this just general welding or does the pipeline need to meet a relevant British Standard etc. In which case your welder would need to demonstrate an ability to weld to the correct technical code/standard. If so safety critical test/demonstartion welds are usually in order with possibly NDT inspections afterwards.

Posted By Phil Atkinson Thanks - all good comments. The pipe will be welded directly, but will be purged beforehand. I was looking for advice on the welders qualifications (i.e. coded) to weld pipework to a standard that would withstand the pressure once re-commissioned. I am aware that there are a multitude of different "codes" for welders and that it is important to choose the right one for the job. Thanks again and any further comments are welcome