Baker Hughes Masoneilan SVIII AP, Installation And Maintenance Manual

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Masoneilan SVI II AP Installation and Maintenance Manual =
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© 2017 Baker Hughes, a GE company, LLC. All rights reserved.
Filter Regulator and Tubing
The use of a Masoneilan filter regulator with a 5-micron filter is recommended for the air
supply. Use 1
⁄ 4" (6.35 mm) minimum tubing between filter regulator, SVI II AP and the actuator,
with 3 ⁄ 8" (9.53 mm) used for larger actuators. Use a soft setting anaerobic hydraulic seal such
as Loctite Hydraulic Seal 542 for sealing the pneumatic pipe threads. Follow manufacturer’s
instructions.
NOTE
Maximum allowable air supply pressure to the SVI II AP varies
according to actuator and valve size and type. See pressure drop
tables in valve specification sheets to determine correct positioner
supply pressure. Minimum supply pressure should be 5 to 10 psi
(.345 bar - .69 bar) (34.485 - 68.97 kPa) above maximum spring
pressure.
Mounting the SVI II AP on Rotary Valves
This procedure is used to mount the SVI II AP on rotary control valves that have less than 60°
rotation, such as a Camflex or a Varimax
.
For valves that have rotation greater than 60° refer
to “Rotary - 90°” on page 43.
Required Tools
The following tools are needed to complete the rotary valve installation:
3 ⁄ 16" Hex Key with tee handle
5 ⁄ 32", 1/2" Hex Key
3 mm, 4 mm, 5 mm Hex Key
7 ⁄ 16" Wrench
To mount the SVI II AP:
1. Attach the SVI II AP rotary mounting bracket to the valve actuator using two (2) 5 ⁄ 16 - 18
UNC flat-head cap screws. Mount the SVI II AP as shown in Figure 12 on page 41, ATO or in
Figure 13 on page 41, ATC. In the preferred mounting position, the long end of the
mounting bracket is on your left when facing the actuator, for any position of the valve
and actuator.
2. Bolt the extension shaft to the valve position take-off shaft using a 1 ⁄ 4 - 28 UNF socket
flathead screw. Secure the machine screw holding the extension shaft with a torque of
144 in-lbs (16.269 N-m).
3. Upon internal valve pressure the thrust shaft is pushed out to the mechanical stops,
usually a thrust bearing. On valves where the valve position take-off is mounted directly
on the end of the plug shaft, a Camflex for example, the shaft must be bearing on its stop
to properly set up the SVI II AP digital valve positioner. During hydrostatic testing the shaft
is thrust to its stop and a normally tightened packing retains it in that position.