Flowserve Valtek VL Spring Cylinder Linear Actuators - Manual (Page 6)

Valtek Spring Cylinder Linear Actuators FCD VLENIM002-00-AQ 10/14
6
NOTE: Item numbers correspond directly to actuator’s bill of material. Refer to it for specific part numbers.
Figure 4: Cap-spring Cylinder Actuator
Adjusting Screw
(Item No. 210)
Spring Cap
(Item No. 325)
Spring
(Item No. 229)
Cylinder
(Item No. 202)
Spring Guide
(Item No. 326)
Piston O-ring
(Item No. 271)
Yoke O-ring
(Item No. 274)
Cylinder Retaining Ring
(Item No. 256)
Actuator Stem
(Item No. 211)
Stem Bellows
(Item No. 247)
Stroke Plate
(Item No. 213)
Yoke
(Item No. 201)
Adjusting Screw Gasket
(Item No. 248 )
Spring Button
(Item No. 227 )
Cap O-ring
(Item No. 270 )
Actuator Stem Locknut
(Item No. 348 )
Piston Stem O-ring
(Item No. 272 )
Piston
(Item No. 225 )
Upper Stem Bushing
(Item No. 253 )
Actuator Stem O-ring
(Item No. 275 )
Lower Stem Bushing
(Item No. 254 )
Stem Clamp Bolting
(Item No. 240/345 )
Stem Clamp
(Item No. 249 )
O
S
Problem Probable Cause Corrective Action
High air consumption or leakage
Leaks in the air supply or instrument signal
system
Tighten connections and replace any leaking lines
Malfunctioning positioner Refer to appropriate positioner maintenance bulletin
Leaks through O-rings or adjusting screw gasket Replace O-rings or gasket
Actuator does not move to fail
position upon loss of air supply
pressure
Air pressure in cylinder not venting because of
faulty positioner
Refer to appropriate positioner maintenance bulletin
Spring failure Replace spring
Internal valve problem Refer to valve’s maintenance bulletin
Jerky or sticking stem travel
Insufficient air supply pressure Check air supply and any filters or regulators; check for
leaking O-rings
Unlubricated cylinder wall Lubricate cylinder wall with silicone lubricant
Worn or damaged stem bushings Check actuator stem for damage; replace actuator stem,
O-ring, and stem bushings, if necessary
Improperly assembled spring Disassemble actuator and check cylinder and piston for
damage; reassemble actuator correctly
Internal valve problem Refer to valve’s maintenance instructions
Troubleshooting