A Socket Weld is a pipe attachment detail in which a pipe is inserted into a recessed area of a Valve, fitting or flange. In contrast to butt weld fittings,socket weld fittings are mainly used for small pipe diameters (Small Bore Piping); generally for piping whose nominal diameter is NPS 2 or smaller. To join pipe to Valves and fittings or to other sections of pipe, fillet-type seal welds be used.

 

ASME B16.11 Socket Weld Cap Dimensions

Class	DN	NPS	B	D	C(Ave)	C(Min)	J	K
3000	6	1/8″	10.8	6.9	3.18	3.18	9.5	4.8
	8	1/4″	14.2	9.3	3.78	3.3	9.5	4.8
	10	3/8″	17.6	12.6	4.01	3.5	9.5	4.8
	15	1/2″	21.8	15.8	4.67	4.09	9.5	6.4
	20	3/4″	27.2	21	4.9	4.27	12.5	6.4
	25	1″	33.9	26.7	5.69	4.98	12.5	9.6
	32	1-1/4″	42.7	35.1	6.07	5.28	12.5	9.6
	40	1-1/2″	48.8	40.9	6.35	5.54	12.5	11.2
	50	2″	61.2	52.5	6.93	6.04	16	12.7
	65	2-1/2″	73.9	62.7	8.76	7.67	16	15.7
	80	3″	89.8	78	9.52	8.3	16	19
	100	4″	115.2	102.3	10.69	9.35	19	22.4
6000	6	1/8″	10.8	4	3.96	3.43	9.5	6.4
	8	1/4″	14.2	6.4	4.6	4.01	9.5	6.4
	10	3/8″	17.6	9.2	5.03	4.37	9.5	6.4
	15	1/2″	21.8	11.8	5.97	5.18	9.5	7.9
	20	3/4″	27.2	15.6	6.96	6.04	12.5	7.9
	25	1″	33.9	20.7	7.92	6.93	12.5	11.2
	32	1-1 /4″	42.7	29.5	7.92	6.93	12.5	11.2
	40	1-1/2″	48.8	34	8.92	7.8	12.5	12.7
	50	2″	61.2	42.9	10.92	9.5	16	15.7
	65	2-1/2″	73.9	–	–	–	16	19
	80	3″	89.8	–	–	–	16	22.4
	100	4″	115.2	–	–	–	19	28.4
9000	6	1/8″	10.8	–	–	–	9.5	–
	8	1/4″	14.2	–	–	–	9.5	–
	10	3/8″	17.6	–	–	–	9.5	–
	15	1/2″	21.8	6.4	9.35	8.18	9.5	11.2
	20	3/4″	27.2	11.1	9.78	8.56	12.5	12.7
	25	1″	33.9	15.2	11.38	9.96	12.5	14.2
	32	1-1/4″	42.7	22.8	12.14	10.62	12.5	14.2
	40	1-1/2″	48.8	28	12.7	11.12	12.5	15.7
	50	2″	61.2	38.2	13.84	12.12	16	19
	65	2-1/2″	73.9	–	–	–	16	–
	80	3″	89.8	–	–	–	16	–
	100	4″	115.2	–	–	–	19	–