2-7/8" Three-Blade Spiral PDM Mud Motor for Coal Mining

Product Introduction

Engineered specifically for the demanding and unpredictable environments of underground coal extraction, this 2-7/8" OD positive displacement mud motor transforms the hydraulic energy of drilling fluids into a steady, powerful mechanical torque. Operators handling the unit will immediately notice its heavy, solid metallic build, a testament to the high-strength powertrain, universal shaft, and precision bearing assemblies housed within. These core components ensure that downhole torque is transmitted smoothly and efficiently, minimizing vibration feedback to the surface. The motor features a meticulously machined 1.25° fixed bent housing, optimized to deliver acute trajectory control for complex directional drilling, horizontal wells, and sidetracking tasks.

By integrating a 5:6 lobe ratio and a 5-stage rotor-stator configuration, it perfectly matches drill bits ranging from 3-3/4" to 4-3/4", ensuring consistent RPM and torque under varying flow rates. The rotor itself is treated with an advanced anti-shedding wear-resistant coating, significantly extending its operational lifespan even when grinding through highly abrasive mixed coal and rock seams. Utilizing standard 2 3/8 PAC thread connections on both ends, it integrates securely into existing drill strings and accommodates both tricone and diamond drill bits. This makes it an essential, highly adaptable drive unit for gas drainage, water exploration, and intricate geological probing.

Product Advantage

Xinyongjia hydraulic downhole mud motors have obtained official API international certification. Key advantages of our coal mine downhole mud motors are listed below:

1.This positive displacement mud motor takes clean water as driving medium, suitable for water-based drilling operation of underground coal mine PDM drilling motor without complex mud circulation system.

2.Equipped with professional triple anti-drop assembly, the coal mine downhole mud motor greatly lifts safety coefficient during underground drilling and avoids falling accidents in boreholes.

3.Our hydraulic PDM drilling motor adopts heavy-duty durable drilling configuration, which extends service life and delivers stable performance in tough coal seam drilling environments.

Product Advantage

4.The outer contour of this downhole mud motor supports optional slick surface, spiral design or spiral structure with three straight blades to satisfy diverse coal mine borehole drilling demands.

5.Customers can select non-magnetic material or high-strength alloy steel for the coal mine screw motor to fit various complex underground coal mine drilling working conditions.

Technical Parameters

Product Uses

Application Scenarios of Xinyongjia 5LZ73X7.0-5 Hydraulic Steel Screw Motor

1. Coal Mine Gas Drainage Drilling

   Navigating narrow, poorly lit mine tunnels requires compact equipment. This 2-7/8 inch mud motor delivers the steady rotational torque necessary to bore extensive horizontal drainage networks deep into the coalbed. By accurately steering the drill bit, it facilitates the safe extraction of hazardous coalbed methane, effectively venting the gas before active mining commences and ensuring a secure environment for the underground crew.

2. Coal Mine Roadway & Side Drilling

   When reinforcing mine roadways or executing sidetracking operations, operational space is severely limited. This miniature hydraulic motor bites into the coal ribs with consistent force, drilling precise branch holes without the need for massive, cumbersome surface rigs. Its exceptional maneuverability and compact footprint improve overall construction efficiency, allowing engineering teams to stabilize volatile rock layers and secure the roadway structure rapidly, thereby minimizing operational delays.

3. Coalfield Geological Exploration Drilling

   Before advancing the mining face, crews must thoroughly understand the geological makeup ahead to avoid operational hazards. This motor powers short-distance directional exploration holes, grinding effortlessly through unpredictable mixed coal-rock formations. The stable power output handles sudden changes in rock density with ease, helping operators accurately map out hidden water pockets and fault lines. This critical predictive capability prevents unexpected water bursts during excavation, safeguarding both personnel and machinery.

Product Operate Guide

Proper on-site assembly and diligent maintenance are critical for maximizing the operational lifespan of your drilling tools. Before deployment, operators must perform a comprehensive pre-run inspection. This involves physically verifying the smooth, unhindered rotation of the rotor and visually confirming the structural integrity of the 1.25° bent housing. When making up the tool string, strictly adhere to the recommended torque standards for the 2 3/8 PAC threaded connections; operators should feel a solid, secure engagement to prevent galling or thread failure under intense downhole pressure. Because the motor relies on a clean water drive, it is essential to ensure the fluid is entirely free of large abrasive particles that could prematurely wear the stator elastomer. After pulling out of the hole, immediately flush the internal chambers thoroughly with clean water to remove corrosive coal dust and debris. For a complete breakdown of torque specifications, troubleshooting steps, and maintenance schedules, refer to our comprehensive technical documentation below.

Xinyongjia Downhole Motor Manual(Chinese -English)

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