Structure	Roller Chain
Flexible or Rigid	Rigid
Standard or Nonstandard	Standard
Material	Steel
Brand Name	DB
Place of Origin	Shandong, China (Mainland)
Model Number	2-3/8"-20"
Standard	API 5CT 5B
Material	J55,K55,N80,L80,P110
Type	NUE EUE

Details of API Spec 5CT&5B oil tubing coupling
API non-upset tubing coupling — Dimensions, tolerances and masses
Label 1	Outside diameter Wb mm	Minimum length NL mm	Diameter of recess Q mm	Width of bearing face b mm	Maximum bearing face diameter Bf mm	Mass kg
2-3/8	73.02	107.95	61.93	4.76	66.68	1.28
2-7/8	88.90	130.18	74.63	4.76	80.98	2.34
3-1/2	107.95	142.88	90.50	4.76	98.42	3.71
4	120.65	146.05	103.20	4.76	111.12	4.35
4-1/2	132.08	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, ±1 %.

API external-upset tubing coupling— Dimensions, tolerances and masses
	Size"	Outside diameter				Width	Maximum bearing face diameter		Mass kg
Label 1	Outside diameter        mm	Regular special bevel Wb            mm	Special clearance Wce mm	Minimum length                mm	Diameter of recess        mm	of bearing         regular                      mm	Special bevel mm	Special clearance mm	Regular	Special clearance
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 W, ± 2 %;
c   Tolerance on outside diameter Wc, ± 0,39 mm.

Details of API Spec 5CT&5B oil casing coupling
API Round-Thread Casing Coupling- Dimensions, tolerances and masses
	Size3	Outside Diameter mm	Minimum Length mm		Diameter of		Width of bearing face	mess  kg
Label 1	Outside diameter mm		Short	Long	recess mm			Short		Long
1	2	3	4	5	6		7	8		9
4-1/2	114.30	127.00	158.75	177.8	116.68		3.97	3.62		4.15
5	127.00	141.30	165.10	196.85	129.38		4.76	4.66		5.75
5-1/2	139.70	153.67	171.45	203.20	142.08		3.18	5.23		6.42
6-5/8	168.28	187.71	184.15	222.25	170.66		6.35	9.12		11.34
7	177.80	194.46	184.15	228.60	180.18		4.76	8.39		10.83
7-5/8	193.70	215.90	190.50	234.95	197.64		5.56	12.30		15.63
8-5/8	219.08	244.48	196.85	254.00	223.04		6.35	16.23		21.67
9-5/8	244.48	269.88	196.85	266.70	248.44		6.35	18.03		25.45
10-3/4	273.05	298.45	203.20	-	277.02		6.35	20.78
11-3/4	298.45	323.85	203.20	-	302.42		6.35	22.64
13-3/8	339.72	365.12	203.20.	-	343.69		5.56	25.66
16	406.40	431.80	228.60	-	411.96		5.56	34.91
18-5/8	473.08	508.00	228.60	-	478.63		5.56	54.01
20	508.00	533.40	228.60	292.10	513.56		5.56	43.42		57.04
API Buttress-Thread Casing Coupling- Dimensions, tolerances and masses
4-1/2	114.30	127.00	123.82	225.42	117.86	3.18		4.55	3.48
5	127.00	141.30	136.52	231.78	130.56	3.97		5.85	4.00
5-1/2	139.70	153.67	149.22	234.95	143.26	3.97		6.36	4.47
6-5/8	168.28	187.71	177.80	244.48	171.83	6.35		11.01	5.65
7	177.80	194.46	187.32	254.00	181.36	5.56		10.54	6.28
7-5/8	193.70	215.90	206.38	263.52	197.23	7.94		15.82	9.29
8-5/8	219.08	244.48	231.78	269.88	222.63	9.52		20.86	10.80
9-5/8	244.48	269.88	257.18	269.88	248.03	9.52		23.16	12.02
10-3/4	273.05	298.45	285.75	269.88	276.61	9.52		25.74	13.39
11-3/4	298.45	323.85	-	269.88	302.01	9.52		28.03	-
13-3/8	339.72	365.12	-	269.88	343.28	9.52		31.77	-
16	406.40	431.80	-	269.88	410.31	9.52		40.28	-
18-5/8	473.08	508.00	-	269.88	476.99	9.52		62.68	-
20	508.00	533.40	-	269.88	511.91	9.52		50.10	-
a The size designation for the coupling is the same as the size designation for the pipe on which the coupling is used
b Groups 1,2 and 3 : Tolerance on outside diameter W + 1% but not greater than + 3.18mm
c Group 4: Tolerance on outside diameter W + 1 % but not greater than mm
d Groups 1,2 and 3 : Tolerance on outside diameter Wc, mm