Groth 1200A - Manual (Page 4)

3
SAFETY WARNINGS:
This section is an overview of safety guidelines
that should be followed during the installation,
operation and maintenance of Groth Pressure/
Vacuum Relief Valves. To understand the context
of these instructions and warnings, it is necessary
to completely read and understand the contents of
this manual.
The purpose of a weight loaded pressure/vacuum
relief valve is to prevent excessive pressure or
vacuum in a tank or process system. The valve
must be designed for the proper MAWP and flow
requirements of the system. Consult API Standard
2000 for tank protection sizing procedures. An
improperly specified or functioning relief valve may
result in structural damage to the tank or system,
and can cause severe personal injury or death.
Valves are set at the factory according to purchase
specifications. Do NOT change pressure ratings
by adding additional weights to the pallet assembly
without consulting the factory or your local Groth
representative. Adding weights to a valve may
restrict pallet lift and reduce the valves’ rated flow
capacity.
DO NOT mix pressure/vacuum pallet assemblies.
Failure to ensure that both pallet assemblies are
installed in the correct location can change the
pressure and vacuum relief settings. This can
cause a tank failure.
DO NOT attempt to remove the valve from the
tank or process vessel without first bleeding all
pressure from the system. ALTERNATIVE
MEANS OF PRESSURE RELIEF MUST BE
PROVIDED WHEN THE VALVE IS OUT OF
SERVICE.
The valve has been exposed to process vapors
while in service. Observe all plant procedures and
Material Safety Data Sheets (MSDS) for the
products in the system when inspecting, adjusting
or servicing the valve. Take appropriate safety
precautions regarding eye protection, respiration
and skin contact.
The tank pressure required to discharge the
normal or emergency venting requirements of the
tank will be increased by the amount of back
pressure in the discharge header, on a pipe away
valve configuration. Maximum possible discharge
header pressure must be considered when sizing
the pressure relief valve.
INSPECTION AND STORAGE:
The pressure/vacuum relief valve is carefully
packaged to prevent damage or contamination
during shipping. Inspect all equipment when it is
received; report any damage to the carrier
immediately. The valve should be protected
during handling and storage. Keep all the ports
plugged to prevent intrusion of foreign materials.
Before installation, inspect the unit for indications
of physical damage or internal contamination. If
these are observed, the valve must be
disassembled, cleaned and repaired before
installation.
INSTALLATION
:
A typical valve installation on a tank or vessel is
illustrated in Fig.1 on Page 2 using a Model 1220A
Pressure/Vacuum Relief Valve.
Groth's weight loaded Pressure/Vacuum Relief
Valves are designed to provide tank protection for
both pressure and/or vacuum to +/-1 PSIG
settings. The valves provide full rated flow
capacity at 100% over-pressure. Consult factory
for performance under other conditions.
WARNING: All valves must be installed level as
shown in Fig 1. To achieve nominal flow capacity,
the tank nozzle bore must be at least the same
nominal dimension as the relief valve inlet port.
This series of valves all have 150# ANSI flange
drilling compatibility. Torque guidelines are listed
in Table 1. The valves are NOT rated for full
flange pressure and do not require high bolting
torque. Consult factory for special applications.