Weld repair procedures of aged components in the refineries and power plants: Kuwait and Australia

Petroleum refineries and power plants seek to extend the life of their aging components through weld repairs. Some of the repairs require stress relieving using post weld heat treatment (PWHT). However, PWHT is a cost and time consuming process. This paper provides a brief description of different alternative techniques for PWHT: half-bead welding, temper-bead welding and cold repairs. It presents a short survey about the different repairs techniques with or without the PWHT and their use in refineries and power plants in Kuwait and Australia. Some of these repairs now have had a successful life of over a decade; the oldest is nearly 20 years old. Details of the methods used are described and recommendations made concerning the alternative techniques. The availability of skilled labour turns out to be a decisive issue.