drill collar

Used for well drilling. Standard:  API SPEC 7-1 Steel Grade: AISI 4145H Dimension: 3 1/8" -- 11" Connected  Type: NC, IF, REG、

Drill Collor Number*	OD (in.)	ID (in.)	Length (ft)	Weight (lb/ft)	Typical Bending Strength Ratio
NC 23-31	3-1/8	1-1/4	30	22	2.57:1
NC 26-35 (2-3/8 IF)	3-1/2	1-1/2	30	27	2.42:1
NC 31-41 (2-7/8 IF)	4-1/8	2	30 or 31	34	2.43:1
NC 35-47	4-3 /4	2	30 or 31	47	2.58:1
NC 38-50 (3-1/2 IF)	5	2-1/4	30 or 31	54	2.38:1
NC 44-60	6	2-1/4	30 or 31	83	2.49:1
NC 44-60	6	2-13 /16	30 or 31	76	2.84:1
NC 44-62	6-1/4	2-1/4	30 or 31	91	2.91:1
NC 46-62 (4 IF)	6-1/4	2-13 /16	30 or 31	84	2.63:1
NC 46-65 (4 IF)	6-1/2	2-1/4	30 or 31	100	2.76:1
NC 46-65 (4 IF)	6-1/2	2-13 /16	30 or 31	93	3.05:1
NC 46-67 (4 IF)	6-3 /4	2-1/4	30 or 31	109	3.18:1
NC 50-70 (4-1/2 IF)	7	2-1/4	30 or 31	118	2.54:1
NC 50-70 (4-1/2 IF)	7	2-13 /16	30 or 31	111	2.73:1
NC 50-72 (4-1/2 IF)	7-1/4	2-13 /16	30 or 31	120	3.12:1
NC 56-77	7-3 /4	2-13 /16	30 or 31	140	2.70:1
NC 56-80	8	2-13 /16	30 or 31	151	3.02:1
6-5/8 API Reg	8-1/4	2-13 /16	30 or 31	162	2.93:1
NC 61-90	9	2-13 /16	30 or 31	196	3.17:1
7-5/8 API Reg	9-1/2	3	30 or 31	217	2.81:1
NC 70-97	9-3 /4	3	30 or 31	230	2.57:1
NC 70-100	10	3	30 or 31	243	2.81:1
8-5/8 API Reg	11	3	30 or 31	300	2.84:1