GB/T 898Double end studs b1=d—— type B
GB/T 9125Fasteners for pipe flange joints—Double end studs—Commodity fastener
GB/T 953Double end studs (clamping type)—Standard type
HG/T 20613Bolting for use with stral pipe falanges-Double end sutds
Q 124Double end studs b1=1.25d
Q 128Double end studs(clamping type)
QC/T 870Double end studs b1=1.25d
SH/T 3404Fasteners for pipe flanges—Double end studs