Pilot Installation - Emerson ANDERSON GREENWOOD 727 Installation And Maintenance Instructions Manual

ANDERSON GREENWOOD TYPE 727 DUAL PILOT MANIFOLD
INSTALLATION AND MAINTENANCE INSTRUCTIONS
8 PILOT INSTALLATION (SEE FIGURE 10)
This valve assembly requires the installation of
two cartridge pilots assembled as instructed in
Section 5. Each pilot installation requires two
seals: a metal O-ring dome isolation seal (528)
and a main pilot metal wedge seal (529). Install
each pilot and its seals as follows:
WARNING!
The metal O-ring used on this pilot is a thin walled
hollow tube and therefore should be handled with
some care when installing to prevent bending
or denting that may reduce its sealing ability.
Similarly, the main metal wedge seal depends
on its sharp inner and outer edges for sealing
and therefore these edges must be protected
from denting and/or nicks during the seal's
handling and installation.
1. Lubricate the metal O-ring (528) lightly
with Fluorolube and install it on the pilot
body (500) using O-ring installation tool
(Anderson Greenwood Part no. 06.2978.001)
to expand it over the tapered ring expander
section and onto the pilot body sealing
diameter.
2. Inspect the valve manifold pilot socket to
ensure that its pilot mounting threads are
clean and free of burrs, its seal bores are
clean and it is clear of debris.
Note: do not use any sharp edged tools
to clean or deburr sealing surfaces in
the manifold pilot socket.
3. Insert the metal wedge seal (529) into the
manifold pilot socket's seal counterbore
with the conical taper upward.
4. Insert the cartridge pilot into the manifold
socket until its mounting bushing engages
the socket thread and then tighten the
bushing by hand as far as possible.
Note: the pilot bushing threads are coated
with a baked-on high temperature friction
reducing coating and therefore do not
require additional lubrication but may
be lubricated lightly if preferred.
5. The pilot bushing tightening procedure
during pilot installation is performed using
a 2" open end wrench. To perform this
step, slowly tighten the pilot bushing until
a sharp rise in bushing turning resistance
indicates that the pilot and seal are fully
seated metal-to-metal with the manifold
and the wedge seal is fully engaged. The
maximum torque required to accomplish
this tightening step is approximately 70 to 80
ft·lb.
Note: during this tightening process there
may be two initial increases in turning
resistance felt prior to final seating of the
pilot. These increases are caused first, by
the engagement of the metal O-ring with
the manifold body and second, as the wedge
seal engages initially and then deforms as
it seals with the manifold.
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