Carbon Steel 90D ELBOW(SR),ASTM A234 WPB,SMLS,SCH.20
Sch is short for schedule,said wall thickness and pipe fittings size is specified with two non-dimensional numbers:a nominal
pipe fittings size for diameter based on inches,and a schedule (Sched. or Sch.) for wall thickness.
Wall thickness level:Sch10,Sch20,Sch30,Sch40,Sch60,Sch80,Sch100,Sch120,Sch140,Sch160 etc
A234 Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and high Temperature Service
ASME\ANSI B16.9:Factory-Made Wrought Steel Butt welding Fittings
ASME B16.28:Wrought Steel Butt welding Short Radius Elbows and Returns