Oil Tubing Coupling (API Spec 5CT & 5B)
API Non-upset Tubing Coupling-Dimension, Tolerances and Masses
Label 1	Outside Diameter mm	Minimum Length N^Lmm	Diameter of recess mm	Width of bearing face mm	Maximum bearing face diameter mm	Mass kg	Steel Grade
1.050	26.67	80.96	28.27	1.59	30.00	0.23	J55/K55 L80,C90 C95 N80-1/ N80-Q T95,P110 Q125
1.315	33.40	82.55	35.00	2.38	37.80	0.38
1.660	42.16	88.90	43.76	3.18	47.17	0.59
1.900	48.26	95.25	49.86	1.59	52.07	0.56
2-3/8	60.32	107.95	61.93	4.76	66.68	1.28
2-7/8	73.02	130.18	74.63	4.76	80.98	2.34
3-1/2	88.90	142.88	90.50	4.76	98.42	3.71
4	101.60	146.05	103.20	4.76	111.12	4.35
4-1/2	114.30	155.58	115.90	4.76	123.19	4.89
a The size designation for the coupling is the same as the size designation for the pipe on which the coupling is used
b Tolerance on outside diameter W^b, +/-1%

API external-upset tubing coupling--Dimensions, tolerances and masses

API external-upset tubing coupling--Dimensions, tolerances and masses
Label 1	Size	Outside Diameter		Minimum Length mm	Diameter of recess mm	Width of Bearing Regular mm	Maximum bearing face diameter mm		Mass kg		Steel Grade
Label 1	Outside Diameter mm	Regular Bevel W^b mm	Special Clearance W^c mm	Minimum Length mm	Diameter of recess mm	Width of Bearing Regular mm	Special bevel mm	Special clearance mm	Regular	Special clearance	Steel Grade
1.050	26.67	42.16	-	82.55	35.00	2.38	37.80	-	0.38	-	J55/K55 L80,C90 C95 N80-1/ N80-Q T95,P110 Q125
1.315	33.40	48.26	-	88.90	38.89	2.38	42.77	-	0.57	-
1.660	42.16	55.88	-	95.25	47.63	3.18	50.95	-	0.68	-
1.900	48.26	63.50	-	98.42	54.76	3.18	58.34	-	0.84	-
2-3/8	60.32	77.80	73.91	123.82	67.46	3.97	71.83	69.90	1.55	1.07
2-7/8	73.02	93.17	87.88	133.35	80.16	5.56	85.88	83.24	2.40	1.55
3-1/2	88.90	114.30	106.17	146.05	96.85	6.35	104.78	100.71	4.10	2.38
4	101.60	127.00	-	152.40	109.55	6.35	117.48	-	4.82	-
4-1/2	114.30	141.30	-	158.75	122.25	6.35	130.96	-	6.05	-
a .The size designation for the coupling is the same as the size designation for the pipe on which the coupling is used.
b .Tolerance on outside diameter Wb,+/-1%;
c .Tolerance on outside diameter Wc, +/-0.38 mm

9-5/8" J55 LC casing coupling

OCTG-casing