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Standard Maintenance practices Periodic checking of oil level in the reservoir
Periodic cleaning of suction strainer
Return line filter element to be changed after initial 100 hrsand at 500 hrs there after.
Periodic analysis of oil sample for contamination
Flushing of the system after major breakdown and restart
Mounting of magnets in reservoir to prevent entry offerrous particles
Dont return to the system any fluid that has leaked out
Dont mix two different grades / makes of oil
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Standard Maintenance practices Use clean containers, hoses and funnels for filling the oil
into the reservoir. Use of portable filtration unit isrecommended
Use only cloth for cleaning or wiping of hydrauliccomponents
Ensure proper type and quantity of spare items and properstorage
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Sequence of shutting down the machine for
serviceLower or
mechanicallysecure all
suspended loads
Discharge both
ends of theintensifier
Isolate the
electrical powersupply
Isolate the
electrical controlsupply
Drain down allaccumulators
Exhaust anypressure locked
in the system
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What is to be checked?
The Pressure - For Force of the actuator
The Flow - For Speed of the actuator
The Direction of flow - For the direction of theactuator
Ask questions in terms of pressure, flow and control toidentify the problems
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Trouble shooting
Probable Cause Remedy
Wrong direction of pump rotation Run in specified direction of rotation
Pump shaft not rotating Key not fitted or coupling is loose
Large air entry form the suction
port
Tighten all suction fittings, fill with
hydraulic oil or cover with greaseInsufficient revolution Run at least minimum specified RPM
Failure of vanes to come out of slotsin a vane pump
Disassemble, clean and remove dust in slots
Delivery rate set at set at 0 with a
variable displacement pump
Re adjust the delivery rate
High mounting position Height of pump inlet port to be within onemeter from the oil level in reservoir
Excessive oil viscosity Choose oil with suitable viscosity grade
Worn out or damaged parts Repair or replace the parts
No Flow from the pump:
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Trouble shooting
Probable Cause Remedy
Reservoir fluid level low Top up the Reservoir
Reduced efficiency of oilcooler
Check the temp. of cooling media (Air/ Water)Check for choking of cooling area (Tubes / Fins)Check for quantity of supply of cooling media(Fan angle damage / Water supply)
Correct fluid is not used Drain and refill with correct fluid
The pump output pressure istoo high
Readjust the set pressure of the relief valve to meetwith required system load
Increased internal drain inpump (Wear out)
Measure the drain amount Piston pumpMeasure flow at set pressure Vane pump & Gearpump (volumetric efficiency)
Reservoir surrounding notclear
Clear the area for natural cooling
Excessive Temperature:
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Trouble shooting
Probable Cause Remedy
Pump noisy Air in the system Tighten all suction fittings, fill withhydraulic oil or cover with grease
Air entry through pump shaft seal Replace the shaft seal if worn out
Air bubbles in the reservoir
Return line pipe should terminate belowoil surface in reservoir at any timeLocation of return pipe with respect tosuction pipe to be proper and also flow path
Small size of the suction strainer(Increased suction flow resistance)
Change to larger size suction strainer
Clogged strainer / Filter (Increasedsuction flow resistance)
Clean or replace the strainer / Filterelement
Pump speed is too high Reduce the pump speed to the rated speed
Coupling misalignment Realign motor and pump accurately
Relief valve noisy Setting too lowor too close to another valve setting Adjust to correct pressure
Excessive Noise:
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Trouble shooting
Probable Cause Remedy
The line pressure is out ofthe rated pressure range ofthe seals
Check the seal if it meets with the use for the linepressure. If not replace it
Seal is not compatible withoil
Either swelling or shrinkage can occur due to thechemical reaction. Change the seals to theparticular type of oil used
Deformation due to self lifeof seals
Flatness or hardness may change or degradationcan occur since the seals have a specific self life
The finish of the surfacewhich interferes with theseal is improper
Check the surface area for roughness, burrs andcontaminant particles on the areaRefurnish the surface, Get rid of burrs, clean thesurface area
Oil leakage:
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