Mud Motor Rotor
Leistritz has collaborated with several well drilling equipment and tooling companies to improve manufacturing and find a solution to machining problems long associated with Power Section Rotors. These rotors connect directly to the drill bit in directional drilling for oil and gas discovery deep below the earth’s surface. The power section is a “positive displacement mud motor” combined with directional technology to steer the drill motor using tilting joints and sophisticated, telemetric, sensors. The motor converts the drilling fluid’s hydraulic energy into mechanical energy in the form of torque and rotational speed. This conversion is accomplished through the use of a spiral rotor that fits into a stator of similar shape, to form a tight seal. These systems are now capable of drilling within ±0.15° over depths to 18,000 ft.
Improving Rotor PerformanceThe rotors within the mud motors are called power section rotors, which are typically 5, 7 or 9 lobed with smooth spiral profiles in lengths as long as 8m with long leads of up to 40”. Fit snugly into an elastomer stator having one additional lobe contour with the same lead creates a moineau style progressive cavity positive displacement rotary drive unit. When the water-based drilling fluid or “mud” is pressurized at the surface and pumped down the hole to the power section an extremely high torque low rpm drive is created to rotate the rock crushing drill bits. milling cutter need replacing or indexing several times during the multiple shift operation of each rotor. This and continuous measurements by the operator in the middle of a rotor create unacceptable non-productive time.
Additionally, Leistritz machines also have a milling function as a secondary alternative within the machine tool function. The flexibility of milling allows manufacturers to maintain their known process and add hob tooling as desired for their more commonly produced sizes. The improved rigidity of the Leistritz machine provides for increased cutting speeds & feeds, reducing the milling cycle times by 30-40%.