GB/T 898-1988
Double end studs b1=1.25d-type A
GB/T 898-1988
Double end studs b1=1.25d-type B
HG/T 20613-2009
Bolting for use with stral pipe falanges-Double end sutds
DIN 835-1995
Studes with a length of engagement equal to about 2d
DIN 938-1995
Studs with a length of engagement equal to about 1d
DIN 939-1995
Studs with a length of engagement equal to about 1.25d
DIN 940-1995
Studs with a length of engagement equal to about 2.5d
DIN 949-2-1995
Metric interference-fit thread studs ith a length of engagement equal to about 2d—Type B
CB/T 908-1996
The side of the ship has unequal studs
CB/T 908-1996
An equal-length twin stud is used on the side of the ship
NB/T 47027-2012
Equal-length twin stud for pressure vessel flange -type A
Q 121-1999
Double end studs b1=1.25d
Q 121B-1999
Double end studs b1=1.25d
Q 123B-1999
Double end studs b1=1.25d
Q 123-1999
Double end studs b1=1.25d
Q 124-1999
Double end studs b1=1.25d
Q 125-1999
Double end studs b1=1.25d
Q 129-1999
Double end studs b1=2d
Q 129B-1999
Double end studs b1=2d
HG/T 21573.2-1995
Type BT double end studs with hole-Type I