Description
ELITE Non-magnetic drill collar
Non-magnetic drill collars are made from a low-carbon, high-chromium-manganese alloy steel. They are refining through a strict chemical composition ratio and forging to achieve their mechanical properties, exhibiting excellent low magnetic permeability, high strength, excellent intergranular corrosion cracking resistance, and superior wear resistance. When the magnetic field strength is 1×10⁵/4πA/m, the relative magnetic permeability μr of the non-magnetic drill collar ≤ 1.010.
The magnetic flux density gradient along the inner hole of the non-magnetic drill collar at any distance of 100mm is ≤ 0.05μT.
ELITE’s non-magnetic drill collars use independently developed low-carbon stainless steel, conforming to API specifications and SY/T5144 standards. They can be shot-peened and cold-rolled on the inner hole and threads, and can process double-shoulder threads and other special thread specifications.
- Non-magnetic Drill Collar
The cold rolled finish on both ID and OD surface with a unique technical process strengthens the structure and ensures the tools with optimal resistance to stress, corrosion, cracking, and mechanical performance is greatly enhancing.
Non-magnetic drill collar specifications for your selection:
| Connections | OD mm | ID mm | Length mm |
|---|---|---|---|
| NC23-31 | 79.4 | 31.8 | 9150 |
| NC26-35 | 88.9 | 38.1 | 9150 |
| NC31-41 | 104.8 | 50.8 | 9150 or 9450 |
| NC35-47 | 120.7 | 50.8 | 9150 or 9450 |
| NC38-50 | 127.0 | 57.2 | 9150 or 9450 |
| NC44-60 | 152.4 | 57.2 | 9150 or 9450 |
| NC44-60 | 152.4 | 71.4 | 9150 or 9450 |
| NC44-62 | 158.8 | 57.2 | 9150 or 9450 |
| NC46-62 | 158.8 | 71.4 | 9150 or 9450 |
| NC46-65 | 165.1 | 57.2 | 9150 or 9450 |
| NC46-65 | 165.1 | 71.4 | 9150 or 9450 |
| NC46-67 | 171.4 | 57.2 | 9150 or 9450 |
| NC50-67 | 171.4 | 71.4 | 9150 or 9450 |
| NC50-70 | 177.8 | 57.2 | 9150 or 9450 |
| NC50-70 | 177.8 | 71.4 | 9150 or 9450 |
| NC50-72 | 184.2 | 71.4 | 9150 or 9450 |
| NC56-77 | 196.8 | 71.4 | 9150 or 9450 |
| NC56–80 | 203.2 | 71.4 | 9150 or 9450 |
| 6 5/8REG | 209.6 | 71.4 | 9150 or 9450 |
| NC61-90 | 228.6 | 71.4 | 9150 or 9450 |
| 7 5/8REG | 241.3 | 76.2 | 9150 or 9450 |
| NC70-97 | 247.6 | 76.2 | 9150 or 9450 |
| NC70-100 | 254.0 | 76.2 | 9150 or 9450 |
| 8 5/8REG | 279.4 | 76.2 | 9150 or 9450 |
FAQ
1.Which connections are available?
NC23–NC70 and 6⅝–8⅝ REG as standard; other threads on request.
Api Drill Pipe
2.Do you supply non-magnetic drill collars?
Yes—non-mag alloys with low magnetic permeability for MWD/LWD use.
Api Drill Pipe
3.Can you machine elevator and slip grooves?
Yes—per API 7-1, hardbanding optional.
4.What standard lengths are available?
9150 mm and 9450 mm; special lengths on request.
Non-magnetic BHA components:Non-magnetic drill pipe,Non-magnetic stabilizer.
For an in-depth explanation, see our article on why use non-magnetic drill collar.
Note: Non-magnetic Drill collar is mainly useing to provide bit weight to drill bit so that drill pipe is in tension. Especially non mag drill collar can keep drill bit centralized and hole track by large rigidity. The Drilling collar is manufacturing strictly from API Spec7-1 and SY5411 standards.
- Spiral Drill Collars
Note: Spiral drill collar is using to reduce contact area with the hole so as to avoid efficiently bit sticking from differential pressure. The drilling collars are manufacturing strictly according to API Spec7-1 and Standard SY5144.
- Spiral Drill Collar With Elevator Groove And Slip Groove
Note: Elevator groove and slip groove made on box thread face of slick drilling collar or spiral non mag drill collar. Can be using as lifting sub and safety slip when tripping out. The technical parameters for elevator groove and slip groove are as per API SPEC7-1. Hardbanding is optional at customers’ requests.
