Emerson CROSBY HE ISOFLEX Series Installation, Maintenance And Adjustment Instructions page 4

CROSBY SERIES HE ISOFLEX
INSTALLATION, MAINTENANCE AND ADJUSTMENT INSTRUCTIONS
Installation
• Inlet piping
Many valves are damaged when first placed
in service because of failure to clean the
connections properly before installation.
It is essential that the valve inlet, the vessel
and the line on which the valve is mounted be
cleaned thoroughly of all foreign matter.
Safety valves should be mounted in a vertical
position, directly on the pressure vessel; the
nozzle should have a well-rounded approach
that provides smooth, unobstructed flow
between the vessel and the valve.
A safety valve should never be installed on a
fitting having an inside diameter smaller than
the inlet connection of the valve, as restricted
flow can cause faulty valve operation.
• Outlet piping
Discharge piping should be simple and
direct. Where possible, a short vertical pipe
discharging into the atmosphere is the most
desirable type of outlet piping and affords little
trouble.
Discharge piping should be designed so as not
to impose any loading on the valve. Excessive
discharge piping loads may cause seat leakage
or faulty valve operation. The inside diameter of
the discharge pipe must never be less than that
of the valve outlet.
Valve bodies are provided with pipe ½" NPT
thread openings for drains. These should be
connected to prevent any accumulation of fluid
in the valve body. In addition, it is recommended
that discharge piping also be drained to prevent
any accumulation of fluid.
Welding of body
The valve body should be welded to the boiler in
accordance with applicable code requirements.
The protective cover attached to the top of the
body during shipment should be left in place
until ready for the hydrostatic test of the unit.
If visual inspection is necessary the cover may
be removed but should be replaced.
SELF-ACTUATED SAFETY VALVES
®
NOTE 1 TO FIGURE 2A
Delivered with the body and packaged in small bag are
the following:
- One O-ring (for hydrostatic test)
- One backup ring (for hydrostatic test)
- One hydrostatic test plug pin
NOTE 2 TO FIGURE 2B
Delivered with the superstructure and packaged in a
small box are the following:
- Valve nozzle ring*
- Valve nozzle ring set screw*
- Valve guide ring set screw*
- Seal wires
* Marked with valve identification number.
NOTE
When the above parts are removed from their box, be
sure that the identification of parts to valve number is
maintained and that the parts are stored to facilitate
later recovery for assembly.
Top view - Body
Hydro components (see Note 1)
FIGURE 2A - Valve body as shipped
FIGURE 2B - Valve superstructure as shipped
(see Note 2)
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