Consolidated 2478 Series Pressure Relief Valve Manual
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© 2020 Baker Hughes Company. All rights reserved.
VIII. Introduction
A relief valve is a key safety device that protects against
catastrophic pressure vessel failure. However, if it is not
properly installed, maintained, operated and repaired,
the pressure vessel is like a potential bomb.
For example: A 30-gallon (114 Ltr.) hot water tank at 90
psig (6.21 barg) has 3,138,400 ft-Ib (4,25,5099 N-m) of
energy to flash its water into steam at 330°F (166°C)
if liberated by rupture. Energy of a pound of three
common explosives is:
Black powder
906 ft-Ib (1228 N-m)
Smokeless powder 1260 ft-Ib (1708 N-m)
Nitroglycerin
2,000,000 ft-Ib (2,711,636 N-m)
On this basis, the 30-gallon (114 Ltr.) tank is equivalent
to about 1.5 lb (0.68 kg) of nitroglycerin. Catastrophes,
of course, are not the only loss exposure from improper
safety-valve operation. Overpressure can rupture tubing
and blow out packing. Improperly maintained safety
valves, at times, may relieve at too low a pressure or may
leak, so the boiler never reaches the desired pressure or
full efficiency. The result of these problems is unscheduled
downtime. In summary, proper installation, maintenance
and repair is as important as buying of a reliable valve.
This manual therefore provides instructions for installation,
maintenance and repair of Consolidated Bronze Safety
Valves.
1. The valves should be stored in a dry environment to
protect them from the weather.
2. The valves should never be subjected to sharp
impact. This would be most likely to occur by
bumping or dropping during loading or unloading
from a truck or while moving with a power conveyor,
such as a fork lift truck.
3. Meticulous care should be exercised to prevent
dirt and other foreign materials from entering the
inlet and outlet ports during storage as well as in
installation.
The 2478 Series relief valve is provided with a male NPT
inlet connection and a standard hexagon surface for
easy wrench installation. Exhaust outlets are female NPT
connections suitable for standard size pipe fittings. The
2478 Series relief valve must be connected in an upright
vertical position on equal size fittings. Furthermore, in
no case should the discharge pipe connected to the
valve be of a smaller size than the valve outlet. No stop
valve or other obstruction should be placed between the
equipment and the relief valve.
Thoroughly clean the inlet of the valve before installation
and be sure that no pipe thread compound gets into the
bore of the valve during installation.
During installation do not use excessive wrenching force
that may distort the hex on the valve base. The valve
must not be tightened by means of a pipe screwed into
the outlet. The valve at all times should be free from the
discharge piping. The riser pipe should be large enough
to accommodate the full capacity of the valve without
causing a back pressure build up on the valve.
VI. Handling and Storage
VII. Pre-Installation & Installation Instructions
Do not lift valve
horizontally, hook to
lifting lever or spring.
Prevent dirt from
entering valve outlet
port.
Handle valve carefully.
Do not drop or strike.