Common Failures of Solid Control Equipment

  1. Mud Shaker Issues

The mud shaker in solid control equipment sometimes experiences mud loss, primarily because the drilling fluid discharge exceeds the shaker’s load capacity. Other causes include high drilling fluid viscosity, fine mesh screens that can’t filter the fluid properly, or large amounts of fibrous materials mixed in during leak plugging operations. Additionally, if the screen is not cleaned promptly after stopping circulation, the dried drilling fluid can clog the screen. Addressing these issues promptly can prevent them from recurring.

  1. Desander and Desilter Cone Blockage

Blockage of the desander and desilter cones can render the equipment unusable. This often occurs due to improper use or damage to the mud shaker screen, or because the intake pipes of the desander and desilter pumps lack strainers, allowing large rock particles to enter the cones. Ensuring proper installation and complete parts can prevent this issue.

  1. Agitator Failures

The agitator in solid control equipment frequently breaks down due to high drilling fluid density and viscosity, combined with low agitator power, leading to overuse. Insufficient maintenance, lubrication, and improper installation can also cause failures. Proper maintenance and adherence to operating procedures are crucial for ensuring efficient operation.Unable to mix drilling fluids from different mud tanks or transfer fluids between tanks.Higher investment costs compared to mud guns.Require more space than mud guns.Heavier and require electric power supply.May have blind spots in rectangular or square tanks.May need baffles in some environments.Disadvantages of Drilling Fluid Mud GunsUsing mud guns alone requires many guns, pumps, and pipelines, increasing costs.High-pressure nozzles on mud guns can aerate the drilling fluid.Nozzle wear can lead to high-speed flow and higher power requirements; if not replaced timely, it can overload motors.Directly shooting at sediment can clog pumps or cones.Increases the requirements for mud tanks and related components.

Importance of Solid Control Equipment

Solid control equipment plays a key role in efficient drilling operations by removing unwanted solids, controlling drilling fluid viscosity, and maintaining its properties. This ensures safe, efficient, and cost-effective drilling by protecting equipment, maintaining proper drilling fluid characteristics, and managing cuttings generated during drilling.

 Applications of Mud Pump Hydraulic Ends

Oil and Gas Drilling: Essential for circulating drilling fluid, maintaining wellbore integrity, and preventing blowouts.

Mining: Used for pumping slurry and tailings.

Geothermal Drilling: Handles high temperatures and pressures.

Construction: Pumps grout and concrete, handling high-viscosity fluids and solids.

Types of Drilling

By Geological Design Purpose

Exploration Wells: For determining geological formations and resources.

Development Wells: For resource extraction and field development.

By Depth

Shallow Wells: Up to 1500 meters.

Moderate Wells: 1500 to 2800 meters.

Deep Wells: 2800 to 4000 meters.

Ultra-Deep Wells: Over 4000 meters.

By Location

Land Wells: Onshore drilling including lakes and swamps.

Offshore Wells: In sea, categorized into marine and shallow marine based on water depth.

By Well Trajectory

Vertical Wells: Maintain a vertical path.

Directional Wells: Follow a non-vertical trajectory.

By Drilling Method

Rotary Drilling: Uses a rotary table to drive the drill bit.

Downhole Motor Drilling: Uses hydraulic power to drive a motor at the drill bit.

Percussion Drilling: Uses lifting and dropping motions to break rock.

Top Drive Drilling: Directly rotates the drill string from the top.

By Rig Drive System

Mechanical Drive: Uses diesel engines.

Electric Drive: Uses electric motors.

Hybrid Drive: Combines mechanical and electric systems.

By maintaining and operating solid control equipment properly, drilling operations can be more efficient and safe, ensuring the longevity and reliability of the equipment.

Reason for Use Solid particles in drilling fluids are classified into harmful and beneficial solids. Rock cuttings are the primary harmful solids in drilling fluids. Throughout the drilling process, these cuttings adversely affect the physical properties of the drilling fluid, causing increases in density, viscosity, yield point, fluid loss, mud cake, abrasiveness, stickiness, and flow resistance.

During drilling, rock cuttings can damage oil and gas formations, reduce drilling speed, increase rotary table torque, cause resistance during tripping, lead to sticking and stuck pipe incidents, induce wellbore leakage, and result in blowouts and other downhole complications. Additionally, rock cuttings in drilling fluids cause severe wear on the circulation system.

Using solid control equipment helps manage these issues by removing unwanted solids from the drilling fluid, thus maintaining its desired properties and ensuring the efficiency and safety of the drilling operation.

Function The function of solid control technology is to remove harmful solids from drilling fluids, retain beneficial solids, and meet the performance requirements of drilling fluids for the drilling process.

The most effective and economical method for achieving this is through mechanical removal. Solid control equipment such as shale shakers, desanders, desilters, centrifuges, and degassers are used. The solid control system is an integrated whole, composed of various individual pieces of solid control equipment, rationally combined according to the requirements of the drilling fluid solid control process.

Workflow The shale shaker filters the drilling fluid that returns to the surface through the screen, recovering the liquid phase and discharging the solid phase. The smaller the mesh size, the more solids are discharged, which benefits the subsequent solid control equipment’s operation. On the part of the screen surface not covered by drilling fluid, wetter solid particles continue to move towards the discharge end under vibration. This movement helps in further dewatering and shaking off smaller particles adsorbed on larger particles, which fall through the screen. Shale Shaker Screen Selection Standard  The screen mesh size should be selected such that the drilling fluid covers 75% to 80% of the screen surface.### Common Failures and Solutions in Solid Control Equipment


1.Mud Shaker Issues

Problem: The mud shaker sometimes fails due to excessive drilling fluid discharge exceeding its capacity, high drilling fluid viscosity, fine mesh screens that can’t filter properly, or large amounts of fibrous materials mixed in during leak plugging operations. Another issue could be dried drilling fluid clogging the screen if it isn’t cleaned promptly after stopping circulation.

Solution: Regularly monitor and adjust the discharge rate, use appropriate mesh sizes for the screens, and ensure timely cleaning of the screens after stopping circulation to prevent clogging.


2.Desander and Desilter Cone Blockages

Problem: The hydrocyclone cones in desanders and desilters can become blocked, rendering the equipment unusable. This often results from improper use or damage to the mud shaker screen, and the absence of strainers on the intake pipes of the desander and desilter pumps, allowing large rock particles to enter and block the cones.

Solution: Ensure proper installation and maintenance of the equipment, use appropriate screens, and install strainers on intake pipes to prevent large particles from entering the cones.

  1. Mud Agitator Failures

Problem: Mud agitators frequently break down due to high drilling fluid density and viscosity, combined with low agitator power, leading to overuse and inability to operate continuously. Inadequate maintenance, lubrication, and improper installation can also cause failures.

Solution: Regularly maintain and lubricate the agitators, ensure proper installation, and follow correct operating procedures to maintain efficiency and prevent overuse.

Causes of Solid Control Equipment Failures

Electrical Failures

  1. Unstable Power Supply: Fluctuating power, electromagnetic interference, high or low working temperatures, and lightning strikes can all cause electrical failures.

2.Voltage Fluctuations and Power Outages: Large supply voltage fluctuations and frequent power outages can cause the system to restart often, potentially leading to the loss of system files and inability to start normally.

Mechanical Failures

  1. Blockages and Bearing Damage: Issues such as drum and screw conveyor blockages, damaged main or support bearings of the screw conveyor, loose foundation bolts on the main unit or explosion-proof motor, and rigid connections between the feed inlet and the drilling fluid centrifuge can all lead to mechanical failures.
  2. Long-term Vibration: Prolonged vibration can loosen connectors on some components, causing contact issues.

Environmental Factors

  1. Unsuitable Temperature: Extreme temperatures can cause the internal temperature of industrial control machines to rise, affecting normal operations.
  2. Airborne Particulate Matter: High levels of airborne particles can lead to sticky dust accumulation inside industrial control machines, causing hardware damage.
  3. Ground Vibrations: Strong ground vibrations, such as those generated by motors, can cause significant damage to industrial control machines.
  4. Humidity: Both high and low humidity levels can pose threats to industrial control machines.

Human Factors

  1. Improper Usage: Using incorrect methods due to unfamiliarity with the production characteristics of industrial control machines can lead to issues, such as incorrect application software settings, operating system failures or damage, and virus infections.


Understanding these causes of failures helps in taking appropriate preventive and corrective measures to ensure the proper functioning of solid control equipment.