GB/T 898-1988
Double end studs b1=1.25d-type A
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
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 129-1999
Double end studs b1=2d
Q 129B-1999
Double end studs b1=2d
JIS B1173-1995
Double studs-Class 1 fine teeth(b1=1.25d,L≤125mm)
JIS B1173-1995
Double studs-Class 1 fine teeth(b1=1.25d,L>125mm)
JIS B1173-1995
Double studs-Class 2 fine teeth(b1=1.5d,L≤125mm)
JIS B1173-1995
Double studs-Class 2 fine teeth(b1=1.5d,L>125mm)
JIS B1173-1995
Double studs-Class 3 fine teeth(b1=2d,L≤125mm)
JIS B1173-1995
Double studs-Class 3 fine teeth(b1=2d,L>125mm)
DIN 835-1972
Studes with a length of engagement equal to about 2d