Trepanning and Heat Treatment:
Drill collars are trepanned and drifted to API Spec 7-1. Full-length heat-treatment processes ensure that mechanical properties meet or exceed API Spec 7-1 requirements. A hardness range of 285-341, Brinell hardness and Charpy "V" notch minimum impact strength of 40 ft-lb at 70 F are guaranteed one inch below the surface.
Traceability:
Drill collar material and process traceability are maintained from receipt of the mill's certified raw material to completion of manufacturing. Serial numbers are die stamped on bar bodies.
Rigid Inspection Procedures:
We inspect all our drill collars to ensure compliance with API SPEC 7-1 standards. These inspections include visual dimensional checks as well as ultrasonic inspections over the entire body of the drill collar.
Main Advantages of Application of Our Drill Collar
- Put pressure on the drill bit
- To ensure the necessary strength of compression.
- In the process of drilling well deflection control.
- To reduce the vibration of the drill bit, swing, and beating, so that the drill work smoothly.
Technical Parameters of Our Oilfield Drill Collar
| Type | OD(mm) | ID(mm) |
L(m)
±152.4mm
d |
DF(mm)
±0.4 |
NC23-31 | 79.4 | 31.8 | 9.14 | 76.2 |
| NC26-35 | 88.9 | 38.1 | 9.14 | 82.9 |
| NC31-41 | 104.8 | 50.8 | 9.14or9.45 | 100.4 |
| NC35-47 | 120.6 | 50.8 | 9.14or9.45 | 114.7 |
| NC38-50 | 127 | 57.2 | 9.14or9.45 | 121 |
| NC44-60 | 152.4 | 57.2 | 9.14or9.45 | 144.5 |
| NC44-60 | 152.4 | 71.4 | 9.14or9.45 | 144.5 |
| NC46-62 | 158.8 | 57.2 | 9.14or9.45 | 149.2 |
| NC46-62 | 158.8 | 71.4 | 9.14or9.45 | 150 |
| NC46-65 | 165.1 | 57.2 | 9.14or9.45 | 154.8 |
| NC46-65 | 165.1 | 71.4 | 9.14or9.45 | 154.8 |
| NC46-67 | 171.4 | 57.2 | 9.14or9.45 | 159.5 |
| NC50-70 | 177.8 | 57.2 | 9.14or9.45 | 164.7 |
| NC50-70 | 177.8 | 71.4 | 9.14or9.45 | 164.7 |
| NC50-72 | 184.2 | 71.4 | 9.14or9.45 | 169.5 |
| NC56-77 | 196.8 | 71.4 | 9.14or9.45 | 185.3 |
| NC56-80 | 203.2 | 71.4 | 9.14or9.45 | 190.1 |
| 6-5/8REG | 209.6 | 71.4 | 9.14or9.45 | 195.6 |
| NC61-90 | 228.6 | 71.4 | 9.14or9.45 | 212.7 |
| 7-5/8REG | 241.3 | 76.2 | 9.14or9.45 | 223.8 |
| NC70-97 | 247.6 | 76.2 | 9.14or9.45 | 232.6 |
| NC70-100 | 254 | 76.2 | 9.14or9.45 | 237.3 |
| 8-5/8REG | 279.4 | 76.2 | 9.14or9.45 | 266.7 |
| NC50-67 | 171.5 | 71.4 | 9.14or9.45 | 159.5 |
Cold Rolling: Drill collar thread roots, as well as elevator recess upper radius, are cold-rolled. Cold rolling creates a compressive recess upper radius stress condition that increases fatigue life by minimizing crack initiation.
Phosphate-coated or Copper Plating: All connections are phosphate-coated or copper plated to improve resistance to corrosion.
Slip Groove, Elevator Groove and Size: We offer optional slip and elevator recesses to improve handling efficiency and safety. Unless otherwise specified, slip and elevator recesses are machined in compliance with API spec 7-1 guidelines.
Xi'An TianRui Petroleum Machinery Equipment Company Limited with perfect attitude, product and service, is going to make further development together with customers at home and abroad.
Competitive Advantages
1. We offer high quality products at competitive price.
2. Shortest delivery time.
3. Flexible payment terms.
4. Timely after-sale service.
5. Most of our equipment can be replaceable with international brands.
6. Our products have been exported to Argentina, Egypt, US, Australia, Romania, Pakistan, Dubai, Abu Dhabi, Iran, India, Indonesia, Vietnam, Malaysia and many other countries.
