5/12/2017
TECH-538/D.W.O. 23160
Page 125 of 189
Spool Valve Cleaning (old standard flow manifold)
In favorable conditions (i.e. high quality supply air, healthy actuator) there will be minimal if any
maintenance necessary on the spool valve. If unfavorable conditions exist (i.e. poor supply air quality or
if lubrication and sediment from the actuator is being exhausted through the spool valve) it may
become necessary to clean the spool valve to avoid operational failures due to valve sticking and to
maintain optimum positioner performance. .
In any case, if the user wants to proceed and service the
manifold, please contact Westlock before doing in order to prevent warranties and guarantees to be
voided
.
To clean the spool valve, the spool piece needs to be removed
Figure 9-7– Diagram for the spool piece removal
Prior to removing the spool, make sure the positioner is out of service and all air pressure has been
bled-off the positioner and the actuator. The spool piece and sleeve can be cleaned using any
non-chlorinated cleaning solvent. To clean the spool, use a clean lint free cloth. To clean the I.D. of the
sleeve a polyester lint free clean room swab is recommended. These items can be obtained from most
industrial supply companies or catalogs.
Important:
do not use an abrasive cleaner on the spool or sleeve. Never buff the spool or sleeve or use
crocus cloth, and never attempt to remove the sharp edges from the spool lands. These practices will
permanently damage the spool assembly and will affect the fit and action of the spool sleeve assembly.
Important:
the spool and sleeve assembly are sold as a precision matched set. Spools are not
interchangeable. To prevent mix-ups it is recommended that only one assembly be cleaned at a time.
In case mix-up happen contact factory for additional support.
Important:
after cleaning, gently insert the spool into the sleeve. Insert straight with a slight rotating
motion. Do not cock the spool. Make sure the spool spins and moves freely. After the spool valve is
cleaned and reassembled the positioner should recalibrated using the auto CAL function.
Important: Some damages caused by improper usage or maintenance may void the warranty
provided by Westlock and its representatives. In case of doubt, consult Westlock about the correct
procedure to follow.
