Drilling Fluid Treatment System Faults and Solutions

2026-05-09

The Drilling Fluid Treatment System, more commonly known as the Solids Control System. It is the heart of solids removal in oil & gas drilling operations. Any solids control system failure directly impacts mud properties, downhole stability, and rig safety. TR Solids Control summarizes the root causes and troubleshooting procedures of the most common failures in the mud treatment system, helping field engineers get back to drilling fast.

drilling fluid treatment system shale shaker screen change

I. Common Fault of Drilling Fluid Treatment System

In daily oilfield operation, the Drilling Mud System often encounters unstable processing efficiency, abnormal vibration, liquid leakage, poor solid-liquid separation and other common faults. Timely judgment of fault symptoms is the first step to maintain the stable operation of the Drilling Fluid Treatment System.

We sort out the typical faults, possible causes and corresponding solutions of the Drilling Fluid Processing System in the form of a clear table, which is convenient for on-site engineers to check and operate quickly.

II. Equipment‑Specific Troubleshooting

1. Shale Shaker

Fault Symptom	Possible Cause	Solutions
No vibration or reduced amplitude	Power trip, burnt motor, loose eccentric weights, broken belt	Check circuit; replace motor; tighten eccentric weights; replace belt
Shaker screen fails too fast (<20 hrs)	tramp metal in feed, insufficient screen tension, wrong vibrator rotation	Install magnet; re‑tension screen; swap two power phases to get correct elliptical motion
Mud bypasses screen (overflow)	screen too fine, low G‑force, mud too viscous	Use coarser mesh; add weight to increase G‑force; treat mud to lower viscosity
Solids pile up, no discharge	overfeeding or uneven flow, shaker not level	Adjust feed gate or install flow splitter; level basket with a spirit level

2. Desander / Desilter

Fault Symptom	Possible Causes	Solutions
Poor separation – underflow too dry, overflow carries sand	feed pressure below 0.2‑0.3 MPa (30‑45 psi), worn hydrocyclone liner	Clean inlet strainer, check pump impeller; replace liner or entire cyclone
Rope discharge (underflow looks like a string)	solids load exceeds cyclone capacity	Check upstream shaker screen for holes, or reduce ROP
No liquid from overflow port	pressure too high, nozzle too small	Adjust pump discharge valve; replace with larger nozzle

3. Vacuum Degasser

Fault Symptom	Possible Causes	Solutions
Low vacuum (<0.05 MPa / 7 psi)	no water in vacuum pump, broken water ring, air leak in tank or suction line	Fill pump with water and adjust water supply; tighten all bolts, replace gaskets
Pump noisy or shaking badly	solids inside pump, excessive impeller clearance	Stop and flush pump and tank; adjust or replace impeller

4. Decanter Centrifuge

Fault Symptom	Possible Causes	Solutions
No solids discharge (plugged)	bowl and screw conveyor packed with solids	① Bar over by hand – if stuck, it's packed; ② Backflush with water while screw turns slowly; ③ If no luck, disassemble and clean
Severe vibration	uneven solids buildup, bad main bearing, loose anchor bolts	Stop and clean; replace bearing; tighten bolts
Poor separation – liquid still has high sand	wrong differential speed, too much feed	Adjust differential to 10‑35 rpm; throttle feed valve
Main bearing >85°C (185°F)	too much or degraded grease	Clean out old grease, then re‑grease with recommended amount (e.g., 1 oz every 200 hours)

shale shaker screen blinding with wet cuttings

III. Preventive Maintenance (Extend Equipment Life)

Equipment	Daily Checks	Weekly / Monthly Tasks
Shale shaker	screen tension, exciter temperature, motor amps	Replace worn screens; tighten eccentric weight bolts
Desander / Desilter	feed pressure, underflow discharge pattern	Pull and inspect cyclone liners; clean nozzles
Centrifuge	bearing temperature, vibration level, gearbox oil level	Add grease; inspect conveyor blade welds
Vacuum degasser	vacuum reading, water ring condition	Clean scale from inside the tank

Troubleshooting the Drilling Fluid Treatment System is straightforward if you follow the principle "outside‑in, step‑by‑step isolation". Combined with a daily checklist and a failure log, most problems can be fixed in under 30 minutes. Use the tables above as your quick reference, and you will reduce non‑productive time (NPT) while keeping the downhole environment safe.