KUNKLE PRESSURE RELIEF VALVES
Operating and Safety inStructiOnS
PRE-INSTALLATION HANDLING
This pressure relief valve is designed to protect
equipment from overpressure. The valve should
be handled with care, not subjected to heavy
shock loads, and protected to prevent dirt from
getting inside. It should be installed correctly.
Failure to do so could result in property
damage or serious injury to personnel. When
hoisting the valve into position for installation,
care should be exercised so that lifting straps
do not contact the valve lift lever. service life
may vary upon condition of service. Check unit
at least once per 8000 hours or longer intervals
based upon site experience.
Before installation these instructions must be fully read and understood
INSTALLATION
1. Mount the valve in a vertical position so that
the valve body is self draining. If a body drain
port is provided, make sure it is open when
required by the ASME code. Do not plug
any bonnet vent openings. The inlet piping
should be as short as possible, with no
elbows, and equal to or greater than the size
of the pressure relief valve inlet connection.
This will help to limit the inlet pressure drop
to 3% or less when the valve is relieving.
2. When discharge piping is connected to valve
outlet, make sure it is self draining if a body
drain port is not used. The valve should not
be connected to any discharge pipe that
contains pressure before the valve opens or
to any pipe where the pressure build-up is
greater than 10% of the set pressure when
the valve is open and relieving.
Discharge piping, other than a short tailpipe,
must be supported. For steam service,
a drip pan elbow or flexible connection
between the valve and the pipe should be
used to prevent excessive pipe stress, due to
thermal expansion, from being imposed on
the valve body.
3. For threaded valves, to prevent sealing
compound from entering and damaging the
valve, apply a small amount of pipe thread
sealing compound to external threads only.
Do not put any sealing compound on the
first thread or on any internal threads. To
do so may cause the sealing compound to
enter the valve and cause seat leakage.
Do not use the valve body or bonnet for
OPERATION
1. Maintain a system operating pressure at
least 5psig or 10% below the set pressure
of the valve, whichever is greater. Operating
too close to the valve set pressure will
cause seat leakage and will shorten the
time between valve maintenance.
2. Do not use the safety valve as a control valve
to regulate system operating pressure.
Excessive operation will cause the seat to
leak and will require more frequent valve
maintenance.
3. ASME Section I and VIII valves equipped with
lift levers are designed to be operated only
when the system pressure is 75% of set
pressure or greater. ASME Section IV valves
may be operated at any set pressure. When
hand operating the valve, hold it open long
enough to purge any foreign matter from
the seat area. If a cable or wire is attached
to the lift lever for remote actuation, make
sure the direction of pull is the same as it
would be if the lever were pulled directly by
hand.
installing the valve in threaded connections.
Use the wrench flats provided to tighten
the valve to the connecting pipe, and do
not overtighten. To do so may cause valve
leakage.
4. For flanged valves, use new gaskets and
tighten the mounting studs evenly.
VCOSI-01867-EN 17/01
Emerson.com/FinalControl © 2017 Emerson. All rights reserved.
