Major Radius STD 90 Elbow Standard:ASME/ANSI B16.9;GBGB12459; SH3409 Material:alloy Certificate:ISO9001:2008 Major Radius STD 90 Elbow1.According to R: Major Radius or Semi-major Axis R is equal to 1.5D; Short Radius is equal to D.2. According to Pressure Grade:Sch5s,Sch10s,Sch10,Sch20,Sch30,Sch40s,STD,Sch40,Sch60,Sch80s,XS;Sch80,Sch100,Sch120,Sch140,Sch160,XXS3. According to degree: 45,90,180 as ...