Drill Collars
Our drill collars, are made from ultrasonically tested bars of Chrome Molybdenum Alloy Steel (AISI 4145H modified material) and available in all sizes and connections as per API std 7 & API-RP 7G in Range 2. Drill collar bars are fully heat treated to 285 to 341 BHN and Charpy impact value of 40 ft. Lb.
Physical Property
| Drill Collar O.D. Range (Inches) | Yield Strength (min.) (psi) (n/mm2) | Tensile Strength (min.) (psi) (n/mm2) | Elongation (min.) with Gage Length 4 Times Diameter | Brinell Hardness (min.) | Charpy (min.) Impact Value Ft Lb. |
| 3.1/8 THRU 6.7/8 | 110,000 / 758 | 140,000 / 965 | 13% | 285 | 40 |
| 7 THRU 10 | 100,000 / 689 | 135,000 / 931 | 13% | 277 | 40 |
Drill Collars can be furnished in sizes and dimensions as per table given below.
| Drill Collar Number | Outside Dia d" | Bore +1/16" -O d" | Length +/-6" L' | Bevel Dia +/-1/64" D"f | Reference Bending Strength Ratio |
| NC 23-31 | 3.1/8 | 1.1/4 | 30 | 3 | 2.57:1 |
| NC 26-35 (2.3/8 IF) | 3.1/2 | 1.1/2 | 30 | 3.17/64 | 2.42:1 |
| NC 31-41 (2.7/8 IF) | 4.1/8 | 2 | 30 OR 31 | 4.61/64 | 2.43:1 |
| NC 35-47 | 4.3/4 | 2 | 30 OR 31 | 4.33/64 | 2.58:1 |
| NC 38-50 (3.1/2 IF) | 5 | 2.1/4 | 30 OR 31 | 4.49/64 | 2.38:1 |
| NC 44-60 | 6 | 2.1/4 | 30 OR 31 | 5.11/16 | 2.49:1 |
| NC 44-60 | 6 | 2.13/16 | 30 OR 31 | 5.11/16 | 2.84:1 |
| NC 44-62 | 6.1/4 | 2.1/4 | 30 OR 31 | 5.7/8 | 2.91:1 |
| NC 46-62 (4 IF) | 6.1/4 | 2.13/16 | 30 OR 31 | 5.29/32 | 2.63:1 |
| NC 46-65 (4 IF) | 6.1/2 | 2.1/4 | 30 OR 31 | 6.3/32 | 2.76:1 |
| NC 46-65 (4 IF) | 6.1/2 | 2.13/16 | 30 OR 31 | 6.3/32 | 3.05:1 |
| NC 46-67 (4 IF) | 6.3/4 | 2.1/4 | 30 OR 31 | 6.9/32 | 3.18:1 |
| NC 50-70 (4.1/2 IF) | 7 | 2.1/4 | 30 OR 31 | 6.31/64 | 2.54:1 |
| NC 50-70 (4.1/2 IF) | 7 | 2.13/16 | 30 OR 31 | 6.31/64 | 2.73:1 |
| NC 50-72 (4.1/2 IF) | 7.1/4 | 2.13/16 | 30 OR 31 | 6.43/64 | 3.12:1 |
| NC 56-77 | 7.3/4 | 2.13/16 | 30 OR 31 | 7.19/64 | 2.70:1 |
| NC 56-80 | 8 | 2.13/16 | 30 OR 31 | 7.31/64 | 3.02:1 |
| 6.5/8 REG. | 8.1/4 | 2.13/16 | 30 OR 31 | 7.45/64 | 2.93:1 |
| NC 61-90 | 9 | 2.13/16 | 30 OR 31 | 8.3/8 | 3.17:1 |
| 7.5/8 REG. | 9.1/2 | 3 | 30 OR 31 | 8.13/16 | 2.81:1 |
| NC 70-97 | 9.3/4 | 3 | 30 OR 31 | 9.5/32 | 2.57:1 |
| NC 70-100 | 10 | 3 | 30 OR 31 | 9.11/32 | 2.81:1 |
| 8.5/8 REG. | 11 | 3 | 30 OR 31 | 10.1/2 | 2.84:1 |
