What are The Hydraulic Problems and Troubleshooting Guides?

What are The Hydraulic Problems and Troubleshooting Guides?

Below are the 5-Category Hydraulic problems with suggested troubleshooting guidelines. Causes are listed according to their probability, along with their remedies.

Hydraulic Problems Sources/Symptoms Possible Problems/Alarm Message Recommended Action
Abnormal/Excessive Noise Pump Cavitation Replace dirty strainers.
Clean clogged inlet line.
Clean reservoir breather vent.
Change to proper pump drive motor speed.
Air in fluid Tighten leaky inlet connection.
Fill the reservoir to the proper level.
Bleed air from the system.
Replace pump shaft seal.
Coupling Tighten coupling.
Check the condition of seals and bearings.
The pump is worn or damaged Repair or replace.
Motor Coupling misaligned or loose Realign coupling.
Check condition.
The motor is worn or damaged Repair or replace.
Mechanical Vibrations Misaligned, loose coupling Realign coupling and remove any unnecessary clearances
Vibration of pipes Tighten pipe clamps and add more clamps where necessary.
Relief Valve Improper setting Install pressure gauge and adjust to correct valve setting pressure. Make sure the setting is not too close to operating pressure or to another valve setting.
Valve is worn or damaged Repair or replace.
Excessive Heat Pulp Pump is worn or damaged Repair or replace.
Relief Incorrect setting Install pressure gauge and adjust to correct setting pressure.
Flow losses between pressure and return sides Pressure set improperly Set pressure to the diagram rating.
Defective valve function or damaged seals Repair or replace it.
Insufficient cooling Cooling water system unavailable Make cooling water available.
Deposits in cooling water system Clean cooling water strainer and equipment.
Tank heater Heater on too much Check program for proper command.
Check disconnect for proper operation.
Viscosity too low Oil damaged Drain and refill with fresh oil.
Water contamination Find and repair water source, then drain and refill with fresh oil.
Improper oil Drain and refill with fresh correct oil.
Incorrect Flow No flow Pump not receiving fluid Replace dirty strainers.
Clean clogged inlet line.
Clean reservoir breather vent.
Pump motor not operating Repair or replace.
Pump-to-drive Check for damaged pump or drive.
Replace and align sheared coupling.
Pump motor rotation incorrect Reverse rotation.
Directional valve in the wrong position Check the position of manually operated valves.
Check electrical circuit for solenoid-operated valves.
Entire flow passing Adjust relief valve over relief valve setting.
Damaged pump Check for damaged pump or drive.
Replace and align coupling.
Low flow Flow control set too low Adjust
Variable displacement mechanism malfunctioning Repair or replace.
Excess flow Flow control set too high Adjust.
Flow losses between pressure and return sides Maximum pressure set too high Re-adjust pressure setting per diagram.
The pressure valve cannot close due to dirt or foreign particles Clean system.
Repair or replace parts.
Cylinder tube, piston, or seal damaged Repair or replace damaged parts.
Seal damaged due to incompatible materials Replace with seals that fit the system or change the hydraulic fluids to fit the seals.
Incorrect Pressure No pressure Dirty pump strainers Replace.
Clean clogged inlet line.
Pump motor not operating Repair or replace.
Pump-to-drive coupling sheared Repair and align coupling.
Pump motor rotation incorrect Reverse rotation.
Directional valve in the wrong position Check the position of manually operated valves.
Check electrical circuit for solenoid-operated valves.
Entire flow passing over relief valves Adjust relief valve setting.
Damaged pump Check for damaged pump or drive.
Replace and align coupling.
Low pressure Reducing valve set too low Adjust.
Reducing valve is worn or damaged Repair or replace.
Relief valve or unloading valve set too low Adjust.
Variable displacement mechanism malfunctioning Check pump compensator.
Repair or replace.
Pump, valve, motor, cylinder, or other component is worn or damaged Repair or replace.
Water contamination Drain, floss, and refill
Erratic Air in fluid Tighten leaky connections.
Fill the reservoir to the proper level.
Bleed air from the system.
Excess pressure Reducing valve or unloading valve set too high Adjust
Variable displacement mechanism Check the pump compensator.
Repair or replace malfunctioning.
Faulty operation No movement No pressure or flow See troubleshooting guides for incorrect flow and incorrect pressure.
Limit device/sequence device inoperative or improperly set Check mechanical, electrical, and/or hydraulic limits and sequence devices.
Adjust, repair or replace.
Mechanical bind not operating Locate and repair bind.
Cylinder or motor damaged Repair or replace.
Low flow See troubleshooting guide for incorrect flow.
Slow movement Fluid viscosity too high Fluid may be too cold or dirty.
Check heating/cooling system.
Change to clean fluid of correct viscosity.
Insufficient pressure See troubleshooting guide for incorrect pressure.
Lack of lubricant Lubricate machine ways or linkage.
Cylinder or motor damaged Repair or replace.
Erratic movements Erratic flow See the troubleshooting guide for incorrect flow.
Air in oil See the troubleshooting guide for air in oil.
Improper pressure See the troubleshooting guide for incorrect pressure.
Foaming Oil Tank Oil level in the tank too low Add oil as required.
Suction line The crack of leaking suction line Repair or replace.
Improper or degraded oil Inadequate anti-foaming agent Replace with proper oil.
Directional Control Valve Position not Changing Coil not picking up Electric failure Fix electric failure and check mechanical spool motion.
Valve spool stuck Impurities between spool and bore Replace valve if necessary.
The throttle set too tight between the main and pilot valve of the two coil solenoid valve Set the throttle at the correct rating.
Proportional valve not responding Valve not receiving set value from the program Locate and fix the electric failure.
Set value received but valve not responding Replace the proportional valve.
Computer Alarm Messages Pressure filter blocked (identified by pump) Replace the old filter with a new filter insert.
Pressure filter blocked for the circulation pump Replace the old filter with new filter insert.
Circulation/Filter pump fault MCC The motor output gives an alarm to the control desk if that pump is not running.
Circulation/Filter pump stopped with main pumps running Check circulation/filter pump for problems.
Hydraulic unit temperature high Check cooling pump operation.
Check the cooler water strainer.
Check water thermostat operation.
Check that none of the pressure relief valves were set too low. If required, correct the setting.
Return filter blocked Replace the old filter with new filter insert.
Hydraulic oil level low Determine what is causing the drop in oil level. Add clean oil. The pumps will stop automatically if the level drops to the shutdown level.
Hydraulic oil level low - pumps stopping Determine what is causing the drop in oil level. Add clean oil. The pumps will stop automatically if the level drops to the shutdown level.
Pump fault MCC or standby pump fault MCC (identified by pump) The motor output gives an alarm to control desk if that pump is not running.