A TYPE AND B TYPE DRILL COLLAR
Type A
●Be Made of alloy steel and the cross sections of the inside and outside pipe are both round.
Type B
●Be Made of alloy steel and the outside pipe has spiral grooves.
| OD(mm) | Yield Stength Mpa | Tensile Strength Mpa | Elongation % | Brinell Hardness HB | Impact APV J |
| 79.4-171.4 | ≥758 | ≥965 | ≥13 | 285-341 | ≥54 |
| 177.8-279.4 | ≥689 | ≥930 | ≥13 | 285-341 | ≥54 |
C TYBE NON-MAGNETIC DRILL COLLAR PROPERTY
Type C
●Made of stainless alloy steel with rather low magnetic permeability and the cross sections of the inside and outside pipe are both round.
| OD(mm) | Yield Stength Mpa | Tensile Strength Mpa | Elongation % | Brinell Hardness HB | Impact APV J |
| 79.4-171.4 | ≥758 | ≥827 | ≥18 |
|
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| 177.6-279.4 | ≥689 | ≥758 | ≥20 |
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Drill Collar
Drill collaris a component of a drill string that provides weight on bit fordrilling. Thiskind of trenchless tool is a thick-walled tubular piece that is machined from a solid bar of steel,usually plain carbon steel but sometimes ofnonmagnetic nickel-copper alloy orother nonmagnetic premium alloys. The solidbar is quenched and tempered toobtain the required mechanical properties, thentrepanned, drifted and threaded.Located at the bottom of the drill string,drill collar is a major component ofbottom hole assembly. The maincharacteristic of this trenchless tool is thickwall (It is generally between38 mm to 53 mm and is equivalent to 4 to 6 timesof that of drill pipe), largergravity and stiffness.
ProductionFeatures：
Superior-qualitygreenpipe&Advanced heat treatment process-HighStrength&hightoughness(especiallyunder low temperature)
●Tomeet or exceed requirements of the API 7-1,API 7g&IS09001
●Equippedwith advanced inspection instruments and a strictly enforced qualitycontrollingsystem,the final products are guaranteed to be of superiorandstablequality.
Due to our qrofessional technicians&productflexibility,we are capable of meetingsome customer' s specific requirements.
Superior Quality Products
In China
:
②Bore Drilling Machine
③NC Spiral Groove Milling Machine
