Objectives
Review and develop techniques to significantly increase the fatigue life of welded steel joints.
Project Outline
Investigate new procedures, using advanced MIG/MAG welding processes (for eg Fronius CMT) and novel backing techniques (avoiding the risk of copper pick-up) such as Cu coated with ceramics and coated Aluminium backing- to improve the geometry of the weld underbead.
Review of other existing and potential techniques such as laser shock peening and ultrasonic peening for fatigue improvement.
Develop further a process of post weld friction processing to modify the joint geometry, remove surface micro-defects and produce favourable stress distribution in the surface of the weld and adjacent area.
Carry out confirmatory fatigue tests on specimens representative of the joint, ie girth welds in pipes.
Report covering recommendations for parameter selection and making suggestions regarding appropriate means of deployment and brief economic analysis for post weld friction processing
Relevant Industry Sectors
Oil and gas, Rail, Construction equipment, Road
Technical and Economic Benefits
Significant extension of fatigue life has the potential to improve safety, potential environmental impact and contribute to the viability of deep water oil and gas fields.