Design and Development of Various Equipments for Welding and Overlay Process Required During Manufacturing of Pressure Vessel

Abstract

Pressure vessel is one of a major component in process industries. Fabrication of pressure vessel is critical task because it consists of different components like shell, head, nozzle, reinforcement pad, skirt etc. During fabrication of pressure vessel various welding and overlay processes are involved like submerged arc welding, tungsten inert gas welding, metal inert gas welding, flux-cored arc welding, and electro slag strip cladding. Amongst these, some processes are carried out manually and some other with automation. During initial stage of welding, manual welding is preferred because there is no set up time required, but manual welding takes high cycle time and weld quality problem may arise . While facing these types of problem in manual welding, an attempt is made in the present work to construct automation type welding machine. Automatic welding gives consistently better quality of weld compared to manual welding. This present work is focused on overlay and welding of ring type joint groove welding by tungsten inert gas welding, overlay in nozzle in 2G condition by metal inert gas welding / flux-cored arc welding, submerged arc welding of nozzle, pad welding. It is required to transfer pressure vessel from one welding machine to another welding machine during fabrication resulting in increased cycle time and posing material handling difficulties. In order to reduce overall time and avoid the need of material handling, compact fixture for welding machines are developed which can be accommodated on desired location of pressure vessel in easy manner.