Description:
The Challenger Downhole Tools Shock Tool effectively reduces impact loading on the bit to extend bit life and reduce bit trips. By isolating axial bit vibrations from the drill string, the shock tool will reduce lateral and torsional drill string vibrations, and related fatigue damage or failure of the rotary connections.
The shock tool allows optimum bit speed to be used under rough drilling conditions, increasing the rate of penetration. The Challenger shock spring rate can be adjusted for additional applications such as, P.D.C. bits and used with vibration tools and MWD.
The Challenger PDC Shock Tool
This design of our Shock Tool is built with PDC bits in mind. The PDC style bit requires far less weight while drilling, the Challenger PDC style Shock is built to operate and perform better with these lower WOB.
The typical shock is used and designed to operate with Roller Cone style bits that require significantly higher WOB than a PDC, we designed a shock to run with a PDC application which allows the shock to operate better at the lower WOB utilizing its entire stroke more effectively.
When ordering shocks WOB and application information should be considered to assure maximum performance from the Shock Tool.
Benefits & Features
- Reduces drill string vibration and impact from MWD systems
- Adjustable spring rate for P.D.C. applications
- Can be provided in both near bit and string applications
- Does not use temperature-sensitive elastomers for shock absorption, therefore is suitable for use in temperatures to 275°F (135°C), with optional seals available for temperatures up to 450°F (230°C)
- Reliable Belleville disc springs provide optimum load/deflection characteristics to maintain consistent contact between bit and formation, effectively reducing impact loading to extend bit life
- Low friction torsional drive permits free vertical movement
- Reduces wear and tear on rig and equipment, and fatigue failures on drill collars and drill pipe
- Automatically compensates for pump open force
- Isolates bit induced vibrations from the drill string
- Pressure balanced to eliminate the effect of downhole hydrostatic pressure
Operation
- If ran with MWD tool, position shock as close to MWD equipment as possible
- With a packed bottom hole assembly, the shock tool may be located a minimum of two drill collar lengths above the top stabilizer, however bit protection will be reduced due to the greater un- sprung mass below the tool.
- For maximum effectiveness, the shock tool should be positioned immediately above the bit.
- Automatic compensation of pump open effect makes the shock tool effective with any combination of bit weight or circulating pressure.

Imperial
Nominal OD (inch) |
Length (ft) |
Inside Diam |
Approx. Weight (lbs) |
Pump Open Area (in2) |
Torsional Limit (ft lbs) |
Tensile Yield (lbs) |
3.50 | 7.8 | 1.00 | 230 | 5.9 | 10,000 | 239,000 |
4.75 | 10.7 | 1.50 | 540 | 11.0 | 20,000 | 561,500 |
6.25 | 11.7 | 2.25 | 1000 | 19.6 | 37,900 | 926,600 |
6.50 | 11.6 | 2.25 | 1030 | 19.6 | 39,500 | 960,000 |
6.75 | 11.5 | 2.75 | 1100 | 21.6 | 46,400 | 837,400 |
8.00 | 11.9 | 2.75 | 1690 | 30.6 | 104,600 | 1,378,800 |
9.00 | 12.3 | 3.00 | 2220 | 38.5 | 125,000 | 1,502,000 |
11.00 | 12.0 | 3.00 | 3240 | 63.6 | 225,600 | 1,628,300 |
12.00 | 12.0 | 3.00 | 3900 | 63.3 | 345,400 | 1,628,300 |
Metric
Nominal OD (inch) |
Length (m) |
Inside Diam |
Approx. Weight (kg) |
Pump Open Area (mm2) |
Torsional Limit (N-m) |
Tensile Yield (daN |
89 | 2.4 | 25 | 100 | 3 800 | 14 000 | 106,300 |
121 | 3.3 | 38 | 250 | 7 000 | 28 000 | 249 800 |
159 | 3.6 | 57 | 450 | 12 700 | 53 000 | 412 200 |
165 | 3.5 | 57 | 470 | 12 700 | 55 000 | 427 000 |
171 | 3.5 | 70 | 500 | 13 900 | 64 000 | 372 500 |
203 | 3.6 | 70 | 770 | 19 700 | 145 000 | 613 300 |
229 | 3.7 | 76 | 1010 | 24 800 | 174 000 | 668 100 |
279 | 3.7 | 76 | 1470 | 41 000 | 313 000 | 724 300 |
305 | 3.7 | 76 | 1770 | 41 000 | 480 000 | 724 300 |