Investigation for defects in hardfacing operation as a part of dual plate check valve manufacturing -A review

The non-return valves specially dual plate check valves are used in many application such as in petrochemical industries, refinery, oil & gas petroleum and cooling water application. It is applicable in downward stream of pump preventing flow reverse, in wellhead injection lines, for oil rings and platforms, in gas and oil processing plants and refinery on delivery/discharge side of pumps, for LNG & chemical storage tank, use on discharge side of pump to prevent the backflow. However since the weld bead geometry necessary for the valve plates & seats to reduce the cost of material because, by this mean the base metal with low cost is used with the sufficient accuracy & life of overlapping surfaces. Hence the geometric accuracy of weld is necessary & expansive process the correct grouping of parameters with counter to weld bead geometry is required. By analysis of different parameters & their control on hardfacing process we can build up new improved & economical process. By which we can get optimum weld bead geometry as well as surface finish with grinding allowance. We are going to take Welding voltage, Welding Current and wire feed rate for analysis. Deep study of these parameters will give us idea about its influence on process.