Protection Caps for Bolts and Nuts

Protection caps are screw-on metal caps designed to protect stud bolts and nuts from thread damage, dirt and considerably help to prevent corrosion. The metal protection caps are the best bolt thread protection and bolt & nut protection for all industrial applications. By using caps you will extend the life of bolts and nuts and make maintenance and repair procedures easier and faster. Commonly installed on heat exchangers, reactors and process equipment, protection caps operates at temperatures up to 550°C and over, where common plastic caps would melt.

Two different models available – either caps protecting bolt thread (TR Type) or both bolt and nut (TD Type)
Available in standard sizes from M21 to M100 – other sizes and coatings upon request
Available in different materials such as aluminium, stainless steel, carbon steel and zinc electroplated carbon steel

Description

Metric
Size	A	B	C	D1	D2
M12	12	24	14	18	18
M14	14	29	16	20	21
M16	16	31	18	22	24
M18	18	34	21	23	27
M20	20	39	23	25	30
M22	22	40	25	32	33
M24	24	45	29	34	36
M27	27	51	30	37	38
M30	30	55	33	40	42
M33	33	61	36	46	48
M36	36	65	39	48	53
M39	39	70	42	52	57
M42	42	77	46	59	62
M45	45	83	49	64	67
M48	48	88	53	67	72
M52	52	94	56	72	77
M56	56	102	60	84	85
M64	64	113	69	91	94
M68	68	119	73	98	105
M72	72	125	77	100	105
M76	76	131	81	105	114
M80	80	136	85	107	114
M90	90	159	95	126	133
M100	100	183	105	144	150

Imperial
Size	A	B	C	D1	D2
1/2″	12,7	27	15	20	20
5/8″	16	34	19	22	24
3/4″	19	39	22	23	30
7/8″	22,3	44	26	33	33
1″	25,5	48	29	37	38
1 1/8″	28,6	55	33	40	42
1 1/4″	31,8	60	36	44	48
1 3/8″	35	65	39	48	53
1 1/2″	38,2	70	42	53	57
1 5/8″	41,3	77	46	59	62
1 3/4″	44,5	83	49	64	67
1 7/8″	47,7	88	53	67	72
2″	51	94	56	72	77
2 1/4″	57,2	105	62	80	85
2 1/2″	63,5	114	69	91	94
2 3/4″	70	125	75	99	105
3″	76,3	136	81	107	114
3 1/4″	82,7	152	87	116	123
3 1/2″	89,2	160	94	126	133
3 3/4″	95,4	172	100	135	138
4″ *	102	183	107	152	151
4 1/4″ *	108	*	*	*	162
4 1/2″ *	114,5	*	*	*	172
4 3/4″ *	121	*	*	*	181
5″ *	127,2	*	*	*	190
5 1/4″ *	133,5	*	*	*	199
5 1/2″ *	140	*	*	*	207
5 3/4″ *	146,2	*	*	*	222
6″ *	152,5	*	*	*	229