Metric Flange Bolt Thread Length

Standard Thread Length (mm)

Flange Bolt Diameter (mm)	Flange Bolts 125mm and shorter	Flange Bolts longer than 125mm
3	12	–
4	14	–
5	16	22
6	18	24
7	20	26
8	22	28
10	26	32
12	30	36
14	34	40
16	38	44
18	42	48
20	46	52