Advertisement
CASH VALVES™ TYPE LTC CRYOGENIC REVERSE ACTING TEMPERATURE REGULATOR
INSTALLATION, OPERATION, AND MAINTENANCE INSTRUCTIONS
INSTALLATION INSTRUCTIONS
Type LTC Regulator is to be installed between
the vaporizer and the service line (or final line)
regulator. The valve should be installed in a
horizontal position with the bellows housing
upright. For other installation requirements
consult the factory. For ease of operation and
maintenance, it is suggested that manual
shut-off valves be installed upstream and
downstream from the valve. Before installing
the valve, the piping should be thoroughly
flushed out to remove any foreign material.
Install the valve so that the arrow cast on the
valve body points in the direction of flow. Use
a compatible sealant on the male pipe threads
and do not over tighten the valve connections.
Exercise care when tightening the unions to
ensure that the gaskets located in the union
ends are properly positioned.
Bulb Installation
Install the thermostatic bulb at a point that is
downstream from the vaporizer but upstream
from the temperature regulator. When a
thermometer is to be installed in the line, it
should be placed directly after the bulb in the
pipe line or at the same level as the bulb in a
tank. The standard bulb is shown in the cut
away view of the valve. A copper well is strongly
recommended for each cryogenic tempera ture
regulator installation, both for the protection
of tho bulb and to allow for the removal of
the capillary bulb without depressurizing
the system.
To install the bulb, remove the bulb bushing
from the bulb. Insert the bulb and fasten
by tightening the nut onto the bushing. The
preferred bulb installation position is with the
end of the bulb below horizontal. Although the
horizontal position is permissible, care must
be exercised to NEVER INSTALL THE BULB
WITH THE END OF THE BULB ABOVE THE
BULB FLANGE.
Note: The flexible armored capillary tubing connecting
the bulb and valve must not be cut, kinked, mashed
or twisted. II may, however, be bent on a 4" radius
or larger. During installation the tubing can be
fastened permanently to a rigid location, how ever,
never connect the capillary tubing to steam pipes,
cold water lines or other loca tions where the tubing
would be subject to extreme temperatures. It is
recommended that a single coil ot tubing be made
next to the regulator to absorb vibrations occurring in
the pipe lines.
OPERATING INSTRUCTIONS
Temperature Adjustment
The temperature regulator can be set to
cut-off the flow of gas at any temperature
from 0 to -40°F (-17 to -40°C) temperature
range. To adjust the cut-off temperature turn
the temperature adjustment wheel (10) in a
counter-clockwise direction to set the regula tor
at a higher temperature. Turn the wheel in a
clockwise direction to set the regulator at a
lower temperature. The wheel is mounted on
ball bearings to eliminate friction and ensure
easy operation.
MAINTENANCE INSTRUCTION
CAUTION
Before attempting to replace any spare parts,
be sure to shut off all pressure connections to
the valve. With the valve closed however, system
pressure could still be locked between the shut
off valve and the inlet and/or outlet sides of the
regulator. Before proceeding with any valve
service, be certain to relieve the pressure from
both sides of the regulator.
When properly applied and correctly installed
the Type LTC Temperature Regulator should
require very little attention or maintenance.
However, the Type LTC, like every mechanical
device, deserves some care to ensure
continued dependability and to protect the
long serv ice life for which it was designed.
When atten tion is required use only genuine
Cash Valve replacement parts.
Refer to the Type LTC Regulator cut
away view for parts identification during
maintenance procedures.
Servicing The Valve Pull Rod Packing (16)
The valve yoke nut should be kept tight. Should
it become necessary to replace the pull rod
packing proceed as follows:
1. Remove the yoke assembly (9) from
the valve body (19) by removing the
yoke nut (13).
2. Remove the spacer (14), female adapter (15),
the two worn packing seals (16), and the
male adapter (17).
3. Replace the packing seals and reassemble
in reverse order. Tighten the yoke
nut securely.
Servicing the Thermal System
The thermal system used on the Type LTC
Temperature Regulator is serviced only as
a complete assembly except for the bulb
bush ing (2) and the bulb gasket (3). The
thermal system is set at the factory to operate
only at the temperature range stamped on
the nameplate which is affixed to the bellows
housing. If it is necessary to install a new
thermal system, the procedure listed below
should be followed.
1. Shut off the vaporizer system.
2. Completely loosen the bushing nut (5), then
take the bulb (1) out of the bulb bushing (2).
3. Turn the temperature adjustment wheel (10)
to its lowest position (counter-clockwise).
4. Remove the screws (8) retaining the bellows
housing (7) to the yoke (9), then lift the
housing from the yoke.
Note: The bellows housing (7) may be under slight
spring tension. Exercise care when removing
the housing.
5. Position the new bellows housing (7) on top
of the spring, aligning the screw holes in the
housing with those in the yoke.
6. Using three 10-32 x 1" screws inserted
in alternate holes in the bellows flange,
tighten the screws evenly to draw the
bellows housing (7) down until it contacts
the yoke (9). Install the shorter standard
screws (8) in the remaining holes, then
replace the 10-32 x 1" slave screws with the
standard screws.
Note: An alternative method of install ing the new
bellows housing to the yoke would be to cool the
thermal bulb to ap proximately -40°F (-40°C) allowing
the bellows to contract and thereby permit ting the
standard screws to be installed.
7. Install the new thermal system bulb (1) in
its original position and lighten the bulb
bushing nut (5).
8. Turn the temperature adjustment wheel
clockwise to its original position or
approximately .675 inches above the
lowest position.
2
Advertisement
