Groth 1660A - Manual (Page 7)

Page 7 of 16
If a vapor leak is detected, it will likely be from
one of the following sources:
1. Pilot
valve
2. Main valve actuator
3. Main valve diaphragm
4. Body - nozzle flange joint gasket
Refer to the troubleshooting guide of this
manual or the pilot valve manual for probable
causes for these types of problems.
WARNING
If the valve must be removed from the tank for
any reason, make sure that all pressure has
been released before the flange fasteners are
loosened. Refer to your company procedures
before venting the tank pressure and when
handling toxic or otherwise hazardous
materials. Observe all standard safety
precautions as specified on Material Safety
Data Sheets for the product(s) in the system
while removing the valve and when repairing
it.
The main and pilot valve actuator housings,
valve bodies, pallet assemblies and other
components are exposed to the process
vapor.
TOOLS
Most service, adjustment and assembly of the
1660A valve can be performed with the
following common tools:
 7/16” - 11/16" open end wrenches
 1/4” - 9/16” socket wrenches
 Adjustable Wrench
 1/16“, 3/32” & 3/16” Allen wrenches
DISASSEMBLY
Note that throughout this manual, numbers
shown in [ ] after the part descriptions refer to
the item numbers in the drawings (Figures 3-
12) and bill of materials, Table 7. Assembly
instructions vary depending on the pallet/seat
configuration and valve size. Exploded views
of the pallet/seat assemblies are included for
clarity.
Observe plant safety procedures in removing
and cleaning the valve before it is sent to a
shop for maintenance. Refer to the SAFETY
WARNINGS listed on page 4 of this manual.
The valve should be handled by the lifting
eyes which are attached to the main valve
actuator housing. It should be supported on
blocks to provide clearance for the outlet
flange during all repair operations.
The external tubing that connects the pilot
valve to the pressure pickup should be
removed first. Loosen the union connection at
the pressure pickup and the tubing fitting at
the pilot body. It is not necessary to remove
the pickup fitting from the body.
Remove the pilot valve [51] from the upper
actuator housing [2] by disconnecting at the
threaded pipe nipple [1]. Inspect and service
the pilot according to the appropriate Groth
manual for either the 1401 or 1402 series
pilots.
Unscrew the hex nuts [6] and lift the upper
actuator housing [2] and gasket [20] carefully
from the valve body. There are two types of
actuator diaphragm support assemblies. The
Model 1660A has one support plate, which is
not attached to the diaphragm. All other
models have the diaphragm sandwiched
between two support plates. Otherwise the
actuator construction is the same for all
models.
If the actuator diaphragm [15] is not attached
to the support plate [4], remove it at this time.
Otherwise, leave it in place and continue.
Lift the lower actuator housing [14], including
the spindle and pallet assembly, from the
body. Remove the second gasket [20].
Check the movement of the pallet assembly
by sliding it until it stops against the spindle
guide [11]. It should move freely with no sign
of binding that may be caused by foreign
materials between the spindle [12] and spindle
guide [11].
Hold the diaphragm support plate [4] while
unscrewing the swivel ball [24] from the
spindle rod [13]. See the following sections
for disassembly and assembly of the specific
pallet types. Remove the spindle [12] from
the guide [11] and inspect the Fluoropolymer
bushing(s) [10] and/or O-Ring seal [67]. The
split bushings are easily removed by prying
from the groove with a sharp probe. Inspect
the spindle surface for scratches or foreign
material.
If the diaphragm is retained between two
support plates, remove the jam nut [47], flat
washer [49], upper (vacuum) support plate
[4.1], and FEP washer [50]. Inspect the
diaphragm carefully to see if there are any
tears, pinholes or signs of chemical
degradation. Remove the lower (pressure)
support plate [4] and O-Ring [48]. All soft
goods should be replaced; refer to Table 5 for
the list of recommended spare parts.