Griffith Shock Tool
Isolate the drill string from axial deflections produced by the bit during drilling operations.
The Griffith™ shock tool isolates the drill string from axial deflections produced by the bit during drilling operations. This reduces impact on the bit and drill string and increases penetration rates by keeping the bit on the bottom during rough drilling conditions. Constant load/deflection characteristics are maintained regardless of hole depth, bit weight, pump pressure, mud weight, or torque. Free vertical movement is assured by guiding the mandrel in the barrel above and below the spline drive to prevent lateral loads from acting on the drive assembly. Griffith shock tools are sprung in both directions to compensate for pump-open forces. The Griffith shock tool contains a chamber and piston to compensate for lubricant expansion at higher operating temperatures. Larger-diameter (11 to 14 in.) tools are designed with a pressure compensation system to reduce the excessive pump-open effect inherent in larger-diameter tools. This design permits a relatively low spring rate, desirable when drilling large-diameter holes, without fully extending the tool at a high pump pressure. The 14-in. shock tools are available with an optional reamer sub for 17½-in. hole size.
Griffith shock tools are available with a standard seal kit rated to 200 °F or an optional higher-temperature seal kit rated at 350 °F.
Hot-hole applications
We also manufacture shock tools designed for hot-hole applications with seals rated above 350 °F. The design and features of the hot-hole tools are similar to the standard tools with the exception of the sealing system required for the high-temperature application.
Small-diameter hydraulic shock tools
We manufactures small-diameter, single-acting hydraulic shock tools in 3⅛-in. (Series 4407) and 3⅜-in. (Series 4405) sizes. Typical applications include coiled tubing drilling. Like the larger-diameter sizes, these tools dampen induced vibrations and increase rate of penetration (ROP) during drilling operations.
When ordering, please specify outer diameter, connections, and bottomhole temperature.
Features
- Will not build angle, as it is well stabilized between barrel and mandrel
- Reduces bit bounce and extends bit life by reducing impact loads on teeth and bearings
- Reduces shock and vibration-induced drill string failures
- Reduces damage to surface equipment
- Unaffected by hydrostatic pressure
Benefits
- Absorbs axial vibration in both directions
- Increases ROP
- Reduces impact on the drill bit
- Protects sensitive downhole electronics
- Reduces vibration-induced drill string failures