3
Troubleshooting
Most problems in fluid power circuits
result in a gradual or sudden loss of
power in the work cylinders, which may
cause them to stall or move slower than
required. This chart assumes that all
other components of the circuit such as
the pump, relief valve, control valves,
hydraulic supply, etc. have been
checked and the problem has been
isolated to the cylinder.
Properly installed and maintained
cylinders should function for millions of
cycles. Premature cylinder failures are
usually caused by system or application
problems that can be prevented. The
purpose of this chart is to aid in identifying
and correcting the most common causes
of premature cylinder failure.
Check Cylinder for
Evidence of:
Caused By:
Action Required:
Excessive wear on
piston rod.
Side load due to misalignment between cylinder
and load.
Check alignment of rod with load connection at
all points in stroke.
Pivot mount cylinder without proper stop tubing.
Follow Vickers cylinder catalog design
recommendations.
Contamination in
cylinder.
Exceptionally dirty environment.
Clean and flush the entire system, deburr
connections.
y
Worn rod wiper/scraper
Shield piston rod area from direct contact with
contaminant.
Impact damage or
b k
t
Lack of, or improperly adjusted cushions.
Reference adjustment instructions in this manual.
g
broken parts.
Load and piston speed combination exceeds
cylinder cushion capacity.
Consult your Vickers Sales Engineer.
Lack of, or improperly adjusted speed controls.
Add or adjust flow controls to reduce piston speed.
Excessive system pressure.
Reduce pressure to minimum required to move
the load.
Permanent deformation
or damaged static
l
System pressure in excess of cylinder rating.
Follow Vickers cylinder catalog design
recommendations.
g
seals.
High pressure developed in cylinder cushion.
Consult your Vickers Sales Engineer.
Cyl. externally loaded while control valve is closed.
Reduce load magnitude or re-size cylinder.
Seal damage such as
loss of elasticity, shape,
t
Excessive temperature in environment or
system.
Install replacement sealing system with proper
rating.
y,
,
etc.
Incompatible hydraulic fluid.
Refer to Vickers cylinder catalog or page 6 of this
manual for compatible sealing system.
Cylinder stored in horizontal position for
extended period.
Replace seals, store vertically with rod up.
Table 1.
Additional Troubleshooting
Information
The following information is intended to
supplement the above troubleshooting
table. Additional details help with the
identification and resolution of frequent
cylinder application problems.
Steps are provided for correcting each
suspected application problem.
1. Excessive Side Load on
Piston Rod
Excessive side loads imposed by
improper alignment or other causes are
a common misapplication of cylinders.
Cylinders may bind, stick, or move
erratically if the operating pressure is
low. Higher operating pressures will
force the cylinder to move, but
eventually cause premature bearing
wear, rod leakage, or extensive cylinder
damage.
High side loads are frequently caused
by improper alignment.
A. Disconnect the piston rod end from
the machine. Observe the alignment
of the rod end at each end of the
stroke and in midstroke.
B. Adjust the cylinder mounting, if
possible, or add a self aligning
coupler on rigid mount cylinders.
C. Additional clearances can sometimes
be added to clevis mount cylinders
to allow some lateral movement
during the stroke.
D. Spherical alignment bushings (SAB
mounts) can be used to allow for
some mounting misalignment.
