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PREP X2R Mud Pump Transmission

New PREP X2R transmission for mud pumping systems.

In the oil and gas drilling industry, innovation and adoption of technology have always been required to keep pace with the growing demand for energy.

For the drilling contractor, a reliable and efficient mud pumping system is a critical component of the drilling rig. The mud system is used to flush cuttings up the well bore, power down-hole motors, provide lubrication to the drilling string, and control surface pressure of the well. The drilling industry has a long history of using reciprocating piston pumps powered by a diesel engine and controlled with a clutch, gearbox, or transmission.

In 1998, Pacific Rim Engineered Products (PREP) developed their first engine mounted transmission with an integral wet clutch, purpose-built for mud pumping. This approach provided tangible benefits over the alternative methods of using air clutches and transmissions adopted from the marine and mobile industrial market place. PREP transmissions are engine mounted directly off the flywheel, and the wet clutch eliminates the power loss typically seen in a torque converter application. PREP’s original transmission design was well received by the industry and has been a success in mechanically driven mud pump packages up to 1300hp.

However, with advances in unconventional drilling techniques, pumping systems require even higher levels of performance. Driven by industry demand for higher discharge pressures and greater productivity while maintaining a compact footprint, PREP developed the X2R 2-speed transmission. The gear train is designed for more powerful engines in order to enable higher pumping pressures and longer component life. The dual-clutch design offers 2 gear ratios to reduce the need for pump liner change-outs and provide a wider operating range of pump speeds and pressures while running the engine at a more efficient speed. For a rig operator, these features directly contribute to increased up-time and reduced fuel consumption.

Traditional methods of using torque converters or air clutches to transmit power often lead to large, heavy and inefficient packages. To offer a compact footprint, PREP optimized the bearing arrangement specifically to accommodate the side load generated by the belt drive and incorporated a new clutch design with a significantly reduced installed length. The X2R’s reduced overall footprint makes it possible to package engines up to 1600HP in a legal transport load configuration.

The X2R’s clutches are serviceable from the rear of the transmission, eliminating the need to remove the transmission from the engine for maintenance. The clutches were also created with a unique design to minimize drag in cold startup. Another feature incorporated in the hydraulic system is the ability to smoothly engage the clutch, or have a soft start of the mud pump, which minimizes shock to the system thereby extending the life of the entire mud pump package. The X2R’s internal lube pump supplies oil for lubrication and clutch engagement, which simplifies packaging and reduces external plumbing. An additional design feature of the transmission is that it uses 15W40 engine oil, common to the diesel engine.

The X2R is supplied with a Transmission Control Module (TCM) that assists the operator in the control and operation of the transmission. The TCM includes a J1939 communication protocol with the engine and an easy-to-use operator interface that displays operating levels and warnings, including oil temperature, clutch pressure, and operating speeds. The TCM has interlocks to inhibit high speed clutch engagement and the ability to automatically disengage the clutch to protect the gearbox from operating outside set parameters.

Over the years, both OEM’s and operators have trusted PREP to develop innovative engineered solutions. PREP’s team specializes in the development of rotating equipment and system designs. Other innovative, power transmission products (up to 6,000hp) can be found in a wide range of industries including transportation, oil & gas, mining and marine.

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