... Process OptimizationThe stainless steel processing, a mandrel molding (can minimize elbow thinned problem), and using the hot carbon steelProcessing, inner disc ... ,347,904LCarbon Steel : ASTM A 234 WPB, WPC ASTM A 105 WPHY 42 , 46 , 52 , 56 , 60 , 65 , 70 , 80Alloy Steel ... Steel Seamless Pipe Fittings,Steel Seamless Pipe Fittings Carbon Steel Elbow