| After-sales Service: | 24/7 |
|---|---|
| Warranty: | 12 Months |
| Manufacturing Process: | Forging |
| Surface Treatment: | Spray-Paint |
| Operation Pressure: | Atmospheric Pressure |
| Material: | Alloy Steel |
| Customization: |
|---|
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Audited Supplier Boban series drill collar is used between the drill pipe and the bit in the drill stem. It is used to put weight on the bit so that the bit can drill.
Materials
Drill collars are manufactured from AISI 4145H modified steel, and are supplied in the "as rolled" surface finish condition. Alternative surface finishes are available.
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.
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
Huanjie offers 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.
Thread Protectors:
Our company offers steel, cast steel and plastic steel thread protectors for its drill stem products.
We supply slick drill collars, spiral drill collars and non-magnetic drill collars; sizes are from 3-1/8 to 11 inches. Besides the drill collars in the table below, we can supply other drill collars at customers' request.
| Nominal size | D | d | L | DF | Bending Strength ratio | ||
| mm | in | mm | in | mm | mm | ||
| NC31-41(2-7/8IF) | 104.8 | 4-1/8 | 50.8 | 2 | 9150 | 100.4 | 2.43:1 |
| NC35-47 | 120.7 | 4-3/4 | 50.8 | 2 | 9150 | 114.7 | 2.58:1 |
| NC38-50(3-1/2IF) | 127.0 | 5 | 57.2 | 2-1/4 | 9150 | 121.0 | 2.38:1 |
| NC44-60 | 152.4 | 6 | 57.2 | 2-1/4 | 9150/9450 | 144.5 | 2.49:1 |
| NC44-60 | 152.4 | 6 | 71.4 | 2-13/16 | 9150/9450 | 144.5 | 2.84:1 |
| NC44-62 | 158.8 | 6-1/4 | 57.2 | 2-1/4 | 9150/9450 | 149.2 | 2.91:1 |
| NC46-62(4IF) | 158.8 | 6-1/4 | 71.4 | 2-13/16 | 9150/9450 | 150.0 | 2.63:1 |
| NC46-65(4IF) | 165.1 | 6-1/2 | 57.2 | 2-1/4 | 9150/9450 | 154.8 | 2.76:1 |
| NC46-65(4IF) | 165.1 | 6-1/2 | 71.4 | 2-13/16 | 9150/9450 | 154.8 | 3.05:1 |
| NC46-67(4IF) | 171.4 | 6-3/4 | 57.2 | 2-1/4 | 9150/9450 | 159.5 | 3.18:1 |
| NC50-67(4-1/2IF) | 171.4 | 6-3/4 | 71.4 | 2-13/16 | 9150/9450 | 159.5 | 2.37:1 |
| NC50-70(4-1/2IF) | 177.8 | 7 | 57.2 | 2-1/4 | 9150/9450 | 164.7 | 2.54:1 |
| NC50-70(4-1/2IF) | 177.8 | 7 | 71.4 | 2-13/16 | 9150/9450 | 164.7 | 2.73:1 |
| NC50-72(4-1/2IF) | 184.2 | 7-1/4 | 71.4 | 2-13/16 | 9150/9450 | 169.5 | 3.12:1 |
| NC56-77 | 196.8 | 7-3/4 | 71.4 | 2-13/16 | 9150/9450 | 185.3 | 2.70:1 |
| NC56-80 | 203.2 | 8 | 71.4 | 2-13/16 | 9150/9450 | 190.1 | 3.02:1 |
| 6-5/8REG | 209.6 | 8-1/4 | 71.4 | 2-13/16 | 9150/9450 | 195.7 | 2.93:1 |
| NC61-90 | 228.6 | 9 | 71.4 | 2-13/16 | 9150/9450 | 212.7 | 3.17:1 |
| 7-5/8REG | 241.3 | 9-1/2 | 76.2 | 3 | 9150/9450 | 223.8 | 2.81:1 |
| NC70-97 | 247.6 | 9-3/4 | 76.2 | 3 | 9150/9450 | 232.6 | 2.57:1 |
| NC70-100 | 254.0 | 10 | 76.2 | 3 | 9150/9450 | 237.3 | 2.81:1 |
Xi′an BOBAN Oil Tools Co., Ltd. Make & Supply a full line of equipment for O& G, horizontal directional drilling (HDD), micro-tunnelling, pipe jacking, etc, In O& G section, we can supply drilling rig component, downhole drilling tools, fishing tools, tubular handling tools, well control equipments, drilling fluid mixing & Recycling system, solid controling equipments and other relevant oiltools,
All our products are API certified, and we are also authorized by ISO: 9001-2000. With advanced production facilities, rigorous quality management, and the joint efforts of our experting staff, Boban has been qualified vendor for many renowned companies in Italy, Germany, Poland, UAE, Kuwait, Egypt, & South East Asia, etc since its establishment in 2018. And obtained a good reputation among the offshore customers as well as other industrial clients.
With our reasonnal prices, quick reaction, high quality products and deliver anywhere on time as well as superior service, Boban has stablished good cooperation relationship with many well-known customers in the world, and also wish to have the chance to work with more and more customers from all over the world!
Pre-Sales Service After-Sales Service
* Transaction Level Five Stars * Supplier Service Five Stars
* Response Rate 86.5% * On-time Shipment Five Stars
* Response Time<12h * Product Quality Five Stars
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Audited Supplier 
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