Drilling Technology (Part 3) — Mud Pump Selection Guide

Mud Pump Selection Guide: Flow Calculation Methods & Key Parameters

​I. Two Core Methods for Flushing Fluid Flow Calculation

1. ​Annular Clearance Formula:
   ​Q=6VF (L/min)
   • ​V: Upward flushing velocity (0.3~0.45 m/s; reduce for loose formations)
   • ​F: Annular area between drill pipe and borehole: ​π(D²-d²)/4 (cm²), where ​D=bit diameter (cm), ​d=drill pipe diameter (cm).
2. ​Empirical Formula:
   ​Q=kD (L/min)
   • ​k: Water delivery coefficient (6~15 L/cm·min; higher for soft rock, lower for hard rock)
   • ​D: Bit diameter (cm).

Case Study: For RadiantLight C1800G (max drill pipe diameter 168mm), Q=10×16.8=168 L/min. This model’s max flow rate (320 L/min) meets operational demands

​II. Critical Roles in Drilling Operations

1. ​Cooling & Lubrication: Prevents overheating of drill bits and reduces friction
2. ​Cuttings Removal: Maintains 0.3–1 m/min upward velocity to flush debris
3. ​Power Transmission: Drives hydraulic tools (e.g., turbo drills)
4. ​Wellbore Stabilization: Forms mudcake to prevent collapse and control formation pressure

​III. Key Selection Criteria

1. ​Flow & Pressure Requirements:
   • Flow rate must match borehole diameter (larger holes need higher flow)
   • Pressure adjusts with depth (deep wells require ≥2.5 MPa)
2. ​Structural Design:
   • ​BW-series piston pumps (e.g., BW250) dominate due to stable output and ruggedness
   • Prioritize corrosion-resistant materials (stainless steel for acidic/abrasive media)
3. ​Operational Flexibility:
   • Hydraulic or gear-driven speed control for variable flow
   • Integrated pressure gauges and flow meters for real-time monitoring

​IV. Maintenance Essentials

1. ​Lubrication System:
   • Replace crankcase oil every 6 months; monitor bearing temperature (<70°C)
   • Grease piston rods and crossheads weekly
2. ​Wear-Prone Components:
   • Inspect piston seals every 50 hours; replace if cracks appear
   • Clean/replace inlet filters daily to prevent clogging
3. ​Safety Checks:
   • Test pressure relief valves monthly to avoid overload
   • Verify seal integrity and tighten bolts during shutdowns

​V. Technical Specifications: BW250 Mud Pump

Usage Tips: Maintain pH 7–8, sand content ≤4%, and suction hose length ≤6m

​VI. Troubleshooting Common Issues

• ​Low Flow/Pressure: Check for air ingress, valve blockage, or worn seals
• ​Excessive Vibration: Realign shafts or replace imbalanced components
• ​Rapid Wear: Use hardened materials (e.g., chrome-plated liners) for abrasive slurries