5assembly of the vl-es actuator – Flowserve Valtek VL-ES Actuators User Manual
Page 7
Valtek VL-ES Actuators FCD VLENIM0114-00 – 09/06
flowserve.com
4.10
Lift the cylinder off the yoke and piston. If excessive O-ring resistance is felt, use a rubber mallet
to gently tap around the cylinder perimeter and gently pry the cylinder off with a flat screwdriver.
Remove the piston quad-seal, and two cylinder O-rings.
WARNING: To avoid serious personal injury, never use air pressure to remove the piston. The piston
may fly out of the cylinder.
4.11
Remove the piston assembly.
4.12
Remove the piston stem, piston and piston O-ring from the actuator stem.
4.13
Remove the O-rings seals from the yoke and end cap.
4.14
The bushings in the yoke and end cap can be pushed out with a press if worn or damaged.
5
Assembly of the VL-ES Actuator
The quad seal and all of the O-rings should be replaced and lubricated with a calcium complex grease
(Dow 55 or equivalent). Silicone O-rings must be lubricated with Magnalube-G lubricant or equivalent.
5.1
Inspect the bushing in the yoke and end cap for damage or excessive wear. Use Table II to
determine if the bushings are useable. Excessive wear on these bushings will affect the cycle life of
the actuator. Replace the bushing if necessary.
Table II: Bushing Tolerances
Actuator
Size
Actuator Stem Bushing
Piston Stem Bushing
Minimum
Maximum
Minimum
Maximum
in.
mm
in.
mm
in.
mm
in.
mm
100
2.252
57.20
2.257
57.33
2.252
57.20
2.257
57.33
200
2.252
57.20
2.257
57.33
2.252
57.20
2.257
57.33
300
2.751
69.88
2.757
70.03
2.751
69.88
2.757
70.03
400
2.751
69.88
2.757
70.03
2.751
69.88
2.757
70.03
5.2 Replacing the yoke and end cap bushings
5.2.1
Remove the old bushings using a press and properly sized pushrods. Take note that the
bushings only push out from one side.
5.2.2
Set the inside bushing by pressing it down to contact the step in the hole. The smaller
bushing is pressed in first. Some bushings may be interchangeable.
5.2.3
Set the outside bushing to be flush with the surface. This provides the correct clearance for
the O-ring to be installed later.
5.3
Inspect the piston stem, actuator stem, piston O-ring and piston for damage or wear. Assemble the
piston assembly using Loctite
®
266 thread locking compound or equivalent. During assembly, a
vice may be used to hold the actuator stem, if desired.
NOTE: When using a vise grip to hold the actuator stem, take care not to damage the stem threads.
5.4
Lubricate and install the four O-rings for the yoke and yoke cap. Lubricate the bushings in the yoke
and yoke cap with a light coat of grease.
c