Most of the hydraulic system failures are similar. That is there is a sudden or gradual loss of pressure or flow. Consequently, cylinders and motors in these systems may stop working. Any of the system components can be at fault.
| Possible causes | Rectification |
| General | |
| Damaged/worn seals | -Replace seals |
| Excessive rod wear | -Prevent wear |
| Rod damaged | -Replace rod |
| Rod seized | -Repair |
| Faulty alignment | -Align properly |
| Broken linkages | -Replace damaged linkages |
| Loose mountings | -Tighten mounting bolts |
| Jerky movement | -Assemble piston packing correctly -Avoid heavy load at slow speed |
| No thrust | -Replace faulty piston -Prevent excessive leakage -Set PRV to correct pressure |
| Abnormal cylinder thrust | -Bleed cylinder of entrained air -Check and set cylinder cushion |
| Erratic operation | |
| Air in system | -Clean filters -Replace worn seals -Drain and flush fluid -Change system fluid -Fill reservoir to proper level -Tighten leaking connections -Bleed air from system -Replace worn shaft/seal |
| Cylinder/valve sticking/binding | -Remove dirt/gummy deposit -Remove fluid contamination -Remove worn parts -Install seals properly |
| Cylinder internal leakage | – Repair or replace worn parts –Tighten loose packing -Use medium viscosity fluid -Control fluid contamination -Control wear |
References:
Categories of malfunctions in hydraulic systems in terms of its general disturbances, and their possible causes and rectification are presented in the above books. Further, the component-wise malfunctions and their potential causes and rectification are also presented.
Joji Parambath
Director
Fluidsys Training Centre
