Down hole motor for Straight Hole / Directional / Horizontal Drilling
1. About the Manual
Roschen Drilling MOTOR is a powerful and reliable positive displacement motor. The motor generates an optimum balance of rotational speed and high torque to drive a variety of drill bits at speeds that maximize tool life and performance. RSM MOTORS offers a choice of flow rates, speeds, and torques to match a wide range of operational parameters. RSM MOTORS are used in applications such as straight hole drilling, directional (steerable) drilling, horizontal drilling, hole opening, and re-entry(work over).
2. ADVANTAGES OF DOWNHOLE MOTOR
Increased rate of penetration.
Better hole deviation control.
Reduction in drill string failure rate.
Reduction in wear and tear of the swivel, Kelly, and rotary drives.
Reduction in fuel cost, since compared to rotary drilling, less energy is required to power a downhole motor.
3. CONSTITUTION
Downhole motors differ in size and performance characteristics, but they share the same basic components as follows (Fig.1) :
Crossover Sub
Safety Catch Sub
Power Section
Coupling Assembly
Bearing Assembly
CROSSOVER SUB
Bobby crossover sub (Fig. 2) provides two functions. Its primary use, serves as a crossover between the motor assembly and the drill stem. It also allows for placement of a float valve.
Safety Catch Sub - This is a safety feature that is incorporated into the design of all Bobby motors. It serves as a retaining device in the event of an external connection failure in the motor (Fig. 3).
POWER SECTION
It consists of stator and rotor. Stator is made by squeezing rubber sleeve on the wall of steel tube, the rubber sleeve inside forms spiral structure with a certain geometric parameter . Rotor is a chrome-plated steel shaft with a helical profile, which runs inside the stator (Fig. 4).
Drilling fluid is pumped downhole through the drill pipe at a given rate and pressure. Once the hydraulic energy of the drilling fluid reaches the motor, that fluid moving through the power section is converted into rotation and torque. This mechanical energy is transferred through the rest of the motor directly to the drill bit.
The power section has many different configurations available. These configurations vary on basis of torque and rpm(rate per meter) requirements, as well as downhole conditions such as temperature and drilling fluids used. helical line on rotor is divided into single end and multi-end ( stator with one more end than rotor). (Fig.
Further technical parameters, pls contact us ROSCHEN, and get details information via roschen@roschen.com .
