Troubleshooting; Excessive Noise And/Or Vibration; Actuator Response Is Sluggish; System Operating Hot - Danfoss 45 Frame K2 Series Service Manual

Service Manual
Series 45 Frame K2 Open Circuit Axial Piston Pumps

Troubleshooting

Excessive noise and/or vibration

Item
Check fluid level in reservoir.
Check for air in system.
Check pump inlet pressure/vacuum.
Inspect shaft couplings.
Check shaft alignment.
Hydraulic fluid viscosity above acceptable limits.

Actuator response is sluggish

Item
Check external system relief valve setting.
Check PC and LS control setting.
Check LS control signal pressures.
Internal system leaks.
Hydraulic fluid viscosity above acceptable limits.
Check external system valving.
Check pump case pressure.
Check pump inlet pressure/vacuum.

System operating hot

Item
Check fluid level in reservoir.
Hydraulic fluid viscosity above acceptable limits.
20 | © Danfoss | April 2017
Description
Insufficient hydraulic fluid causes cavitation.
Air in system causes noisy, erratic control.
Improper inlet conditions cause erratic behavior
and low output flow.
A loose or incorrect shaft coupling causes
excessive noise and/or vibration.
Misaligned shafts create excessive noise and/or
vibration.
Hydraulic fluid viscosity above acceptable limits
or low fluid temperature will not allow the pump
to fill or control to operate properly.
Description
Low external relief valve setting slows down
system.
Low PC setting prevents the pump from
achieving full stroke. Low LS setting limits output
flow.
Incorrect LS signal will not allow pump to
operate correctly.
Worn internal parts don't allow the pump to
operate properly.
Hydraulic fluid viscosity above acceptable limits
or low fluid temperature will not allow the pump
to fill or control to operate properly.
Malfunctioning valving may not allow system to
respond properly.
High case pressure causes the system to be
sluggish.
High inlet vacuum causes low output flow.
Description
Insufficient volume of hydraulic fluid will not
meet cooling demands of system.
Fluid viscosity above acceptable limits or low
fluid temperature will not allow the pump to fill
or control to operate properly.
Action
Fill the reservoir to proper level.
Purge air and tighten fittings. Check inlet for
leaks.
Correct pump inlet pressure/vacuum conditions.
Refer to the Hydraulic Parameters topic.
Repair or replace coupling and ensure that
correct coupling is used.
Correct shaft misalignment.
Allow system to warm up before operating, or
use fluid with the appropriate viscosity grade for
expected operating temperatures. See Hydraulic
Fluids and Lubricants Technical Information
Manual, 520L0463.
Action
Adjust external relief valve setting following
manufacturer's recommendations. External relief
setting must be above PC setting to operate
properly.
Adjust PC and LS setting. Refer to the
Adjustments chapter.
Inspect system to ensure that proper LS signal
transmit to pump.
Refer to Authorized Service Center for required
repair.
Allow system to warm up before operation or sue
fluid with the appropriate viscosity grade for
expected operating temperatures. See Hydraulic
Fluids and Lubricants Technical Information
Manual, 520L0463.
Repair or replace system valving as required.
Correct case drain line restrictions.
Correct inlet pressure conditions.
Action
Fill reservoir to proper level. Verify proper size of
reservoir.
Allow system to warm up before operation or use
fluid with the appropriate viscosity grade for
expected operating temperatures. See Hydraulic
fluids, Series 45 Technical Information Manual ,
520L0519.
AX00000301en-US0101