The purpose of this work is to produce a simple and effective system whereby advantage can be taken of the interrelation between principal variables controlling weld area hardness. It is intended that this system will be able to be used to:
Extend the range of safe application of individual weld procedure qualifications.
Prevent hardness above safe levels from being generated in production welding.
The form of the nomogram that could be used to relate the chemical composition, pipe wall thickness, and welding heat input in weld procedure qualification and field welding has been devised in work performed for PRCI. A series of nomograms can be produced for typical welding scenarios using theoretical predictions, these will take the form shown in the Figure below.
Relevant Industry Sectors
Oil and Gas, Construction and Engineering
Technical and Economic Benefits
2000-3000 per re-qualification of a procedure which could be avoided, at 2001 prices.
Reduction in time taken to reach the final weld procedure.
A more informed definition of suitable combinations of essential variables will not only ensure the widest possible application of a procedure qualification, but should also help prevent hardness levels above this in the procedure qualification weld from being produced in production welding.
Industrial Member Report
Access the Industrial Member Report resulting from this programme: Improving Essential Variables for Hardness Control: A Feasibility Study