WESTLOCK CONTROLS CORPORATION
280 N. MIDLAND AVE., STE. 258, SADDLE BROOK, NJ 07663 TEL: 201-794-7650 FAX: 201-794-0913
www.westlockcontrols.com
10/5/2013
TECH-477/D.W.O. 21424
Page 196 of 206
Spool valve cleaning
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.
To clean the spool valve, the spool piece needs to be removed (see following
diagram). 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
(such as Stoddard solution or volatile mineral spirits). 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.
