Description
Tri-spiral heavy weight drill pipe is specially developed for ultra-deep wells, horizontal wells and extended-reach wells that demand superior bending resistance and hole cleaning capacity over standard HWDP.
Equipped with three equally spaced spiral upset sections, it effectively reduces severe bending stress and contact friction between drill pipe and borehole wall. The spiral thickened structure mitigates buckling deformation, differential pressure sticking, torque and drag during drilling. Meanwhile, the milled spiral grooves efficiently carry rock cuttings away to realize full borehole cleaning.
Compared with standard heavy weight drill pipe, tri-spiral HWDP features heavier single-unit weight and outstanding cuttings transport performance, delivering optimized drilling performance under harsh downhole conditions.
| Nominal Size (in) | Tube | Tool Joint | Weight (lb) | Make-up Torque (ft-lbs) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID (in) | Wall Thickness (in) | Wall Area (sq in) | Section Modulus (cu in) | Cent Upset OD (in) | End Upset OD (in) | Connection Size & Type | Tool Joint OD (in) | Tool Joint ID (in) | Tensile Yield (lbs) | Torsional Yield (ft-lbs) | Approx. Per Foot (lb) | Per Joint (31 ft) | ||
| 2 7/8 | 2 1/16 | 0.688 | 4.727 | 2.672 | 3 1/16 | 2 15/16 | NC26 (2 7/8 IF) | 3 3/8 | 1 1/2 | 520,400 | 22,400 | 18.22 | 565 | 3,800 |
| 3 1/2 | 2 1/4 | 0.719 | 5.645 | 3.460 | 4 | 3 7/16 | NC38 / JSH138 | 4 3/4 | 2 1/4 | 310,500 | 18,500 | 24.88 | 771 | 11,500 |
| 4 | 2 1/2 | 0.825 | 7.411 | 5.225 | 4 1/2 | 4 11/16 | NC40 (4 FH) | 5 1/4 | 2 9/16 | 407,400 | 27,800 | 31.51 | 977 | 14,600 |
| 4 1/2 | 2 3/4 | 0.875 | 9.865 | 7.698 | 5 | 4 11/16 | NC46 (5 FH) | 6 1/4 | 2 13/16 | 548,100 | 43,000 | 43.31 | 1,343 | 22,500 |
| 5 | 3 | 1.000 | 12.661 | 10.661 | 5 1/2 | 5 1/8 | NC50 (5 1/2 FH) | 6 5/8 | 3 | 691,200 | 58,700 | 52.34 | 1,623 | 33,000 |
| 5 1/2 | 3 1/4 | 1.125 | 15.463 | 14.342 | 6 | 5 11/16 | 5 1/2 FH / JSH155 | 7 | 3 7/8 | 799,800 | 70,700 | 63.72 | 1,970 | 41,200 |
| 5 7/8 | 4 | 0.988 | 14.542 | 15.452 | 6 5/8 | 6 | JSHET70 | 7 1/4 | 4 | 799,800 | 70,700 | 57.82 | 1,792 | 39,700 |
| 6 5/8 | 4 1/2 | 1.063 | 18.574 | 22.476 | 7 1/8 | 6 15/16 | 6 5/8 FH | 8 1/2 | 4 1/2 | 1,021,600 | 87,600 | 74.67 | 2,315 | 50,500 |




