Dimensions of U-bolt (to grip pipe) and hook bolts

All dimensions in millimeters

Steel pipes
Nom. pipe size	pip o.d.	A dia.	N	M	K	S max.
15	21.3	8	30	50	25	17
20	26.9	8	35	60	25	10
25	33.7	8	45	65	25	10
32	42.4	8	55	75	25	10
40	48.3	10	60	90	35	16
50	60.3	10	75	100	35	16
65	76.1	12	90	130	45	19
80	88.9	16	105	150	50	19
100	114.3	16	135	175	50	19
125	139.7	16	160	200	50	19
150	168.3	20	190	235	55	19
175	193.7	20	215	260	55	19
200	219.1	20	245	295	55	19
225	244.5	20	270	310	55	19
250	273.0	20	300	350	60	22
300	323.9	20	350	400	60	22
350	355.6	24	385	440	65	22
400	406.4	24	435	500	65	22
450	457.0	24	495	540	70	22
500	508.0	24	540	600	70	22
550	559.0	24	590	650	70	22
600	610.0	24	640	700	70	22
Cast iron pipes
80	98	16	115	160	55	19
^a 100	118	16	135	175	50	19
^a 150	170	20	190	235	55	19
^a 200	222	20	245	295	55	19
^a 250	274	20	300	350	60	22
^a 300	326	20	350	400	60	22
350	378	24	405	460	65	22
400	429	24	455	520	65	22
450	480	24	505	560	70	22
500	532	24	560	620	70	22
600	635	24	660	720	70	22
^a These U-bolts and hook bolts are identical with the equivalent sizes for steel pipe.