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Register here Sign inHeavy weight drill pipe (HWDP) improves the fatigue resistance of the drill string.
Grant Prideco offers three types of heavy weight drill pipe: Standard, Tri-Spiral™, and Spiral-Wate™. Each of these heavy weight drill pipe designs is available in different material grades for standard or critical service conditions.
Standard HWDP
Standard HWDP was developed to provide a gradual transition from heavy drill collars to relatively lightweight drill pipe.
This intermediate-weight pipe has a wall thickness of approximately 1 in. and helps prevent stress concentration at the top of the drill collar section. Heavy weight drill pipe also enables drilling at higher RPMs, reducing torque and differential pressure sticking.
Heavy weight drill pipe is well-suited for directional drilling applications. Because it bends easily, heavy weight drill pipe simplifies directional control and minimizes connection fatigue problems that are common in high-angle or horizontal drilling.
For extended reach and horizontal wells, high-strength heavy weight drill pipe is often used high in the hole to apply weight on the bit. This is especially true for wells in which the total vertical depth to total measured depth ratio is low.
Tri-Spiral HWDP
Grant Prideco developed Tri-Spiral HWDP for applications such as extended reach and horizontal drilling, and it is well-suited for wells requiring additional hole cleaning and buckling resistance.
Severe bending stresses and hole-wall contact are reduced by three spiral upsets that are equally spaced between tool joints. The upset design helps increase buckling resistance, reduce differential sticking, and reduce torque and drag. Spiraling the upsets also helps move the cuttings off the low side of the hole for better hole cleaning.
Spiral-Wate HWDP
Grant Prideco’s Spiral-Wate HWDP saves time and reduces drilling costs, especially in tough drilling environments. Spiral-Wate is designed to handle maximum stress.
Intermediate drill string components are constantly subjected to some of the most severe tasks in drilling today. The critical transition zone between stiff, heavy drill collars (under compression) and the light, more flexible drill pipe (in tension) can be too much for conventional heavy-wall drill pipe to handle.
The unique, patented design of Spiral-Wate reduces differential sticking problems, minimizes wear, and improves circulation. Precision tool joint alignment reduces excessive tool joint wear, resulting in longer service life and reduced fatigue.
Grant Prideco Standard HWDP Specifications
Nominal Size |
Spiral Upsets (in.) |
Connection |
Tool Joint OD × ID (in.) |
Adjusted Weight (lb/ft and lb/jt**) |
2⅞* |
35/16 |
NC 26 |
3⅜ × 1½ |
17.26 and 535 |
3½ |
4 |
NC 38 |
4¾ × 21/16 |
25.65 and 795 |
3½ |
4 |
NC 38 |
4¾ × 2¼ |
23.48 and 728 |
4 |
4½ |
NC 40 |
5¼ × 29/16 |
29.92 and 928 |
4½ |
5 |
NC 46 |
6¼ × 2¾ |
41.45 and 1,285 |
5 |
5½ |
NC 50 |
6⅝ × 3 |
50.38 and 1,562 |
5½ |
6 |
5½ FH |
7¼ × 3¼ |
61.63 and 1,911 |
5½ |
6 |
HT™ 55 |
7¼ × 3¼ |
61.63 and 1,911 |
5⅞ |
6⅜ |
XT™ 57 |
7 × 4 |
57.42 and 1,780 |
6⅝ |
7⅛ |
6⅝ FH |
8 × 4½ |
71.43 and 2,214 |
*2⅞ in. HWDP is only manufactured as an integral (non-welded) design.
**Adjusted weight per joint (lb/jt) is based on 31 ft nominal length per joint.
Grant Prideco Tri-Spiral HWDP Specifications
Nominal Size |
Spiral Upsets (in.) |
Connection |
Tool Joint OD × ID (in.) |
Approx. Weight Incl. Tube and TJs |
2⅞* |
35/16 |
NC 26 |
3⅜ × 1½ |
18.22 and 565 |
3½ |
4 |
NC 38 |
4¾ × 23/16 |
27.05 and 839 |
3½ |
4 |
NC 38 |
4¾ × 25/16 |
24.88 and 771 |
4 |
4½ |
NC 40 |
5¼ × 2⅝ |
31.51 and 977 |
4½ |
5 |
NC 46 |
6¼ × 2⅞ |
43.31 and 1,343 |
5 |
5½ |
NC 50 |
6⅝ × 31/16 |
52.34 and 1,623 |
5½ |
6 |
5 ½ FH |
7 ¼ × 35/16 |
63.78 and 1,977 |
5⅞ |
6⅜ |
XT™ 57 |
7 × 4 |
57.42 and 1,780 |
6⅝ |
7 ¼ |
6⅝ FH |
8 × 4½ |
74.67 and 2,315 |
*2⅞ in. HWDP is only manufactured as an integral (non-welded) design.
**Approximate weight per joint (lb/jt) is based on 31 ft nominal length per joint.
Grant Prideco Spiral-Wate HWDP Specifications
Nominal Size |
Spiral Upset (in.) |
Connection |
Tool Joint OD × ID (in.) |
Approx. Weight Incl. Tube and TJs |
33/16 |
35/16 |
SLH90 |
3⅞ × 2 |
19.48 and 604 |
3½ |
4 |
NC 38 |
4⅞ × 2¼ |
30.39 and 942 |
4 |
4½ |
NC 40 |
5 × 29/16 |
28.90 and 896 |
4½ |
5 |
NC 46 |
6¼ × 2¾ |
49.53 and 1,535 |
5 |
5½ |
NC 50 |
6⅝ × 3 |
59.16 and 1,834 |
5½ |
6 |
5½ FH |
7 × 4 |
55.21 and 1,712 |
5⅞ |
6⅜ |
XT™ 57 |
7 × 4 |
65.38 and 2,027 |
6⅝ |
7⅛ |
6⅝ FH |
8 × 5 |
73.40 and 2,275 |
33/16 in. Spiral-Wate (previously referred to as 2⅞ in.) is manufactured as integral only (non-welded).
6⅝ in. Spiral-Wate is manufactured as integral or Submerge Arc welding.
Performance properties for sizes 3½ through 5⅞ in. reflect those for inertia/friction-welded products.
Sizes 3½ through 5⅞ in. can also be manufactured integrally for special purpose applications.
**Approximate weight per joint (lb/jt) is based on 31 ft nominal length per joint.
