1,Product Name:SW (Socket Welding) Flange 2,Standard:ANSIB16.5,etc ... .RJ RF MFM TG FF RJ SW (Socket Welding) Flange Series:RF SW Flange.MFM SW Flange ... groove,No align deviation,can adjust welding position for flat welding.Disadvantage:The welding stress situation is not so good. ... Easy happening not weld fully welding.Tube system ...