Gardner Denver Reavell H5000 Series, Руководство оператора

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ANCILLARY PARTS
PAGE 81
13.2 SAFETY VALVE – APP167
INSTALLATION AND OPERATING INSTRUCTIONS
SAFETY VALVES
INTRODUCTION
Due consideration should be taken of climatic. Process or other conditions which might adversely affect the
performance of the safety valve. Installation must be undertaken by qualified technicians and to good
engineering practice. In addition, user's attention is drawn to our joint responsibility to ensure that the Health
and Safety at Work Act is not contravened by incorrect installation. Commissioning or servicing. It is
important that the valve to be installed is correct in every aspect, i.e. set pressure, size, material and type
etc. for the application.
STORAGE OF VALVE BEFORE INSTALLATION
Valves should be stored preferably between-5°C and +25°C and a relative humidity of less that 75%. Very
moist or dry conditions should be avoided. If a safety valve is installed after six months, or more, of storage,
it must be subjected to functional test before commissioning. Thread protectors should not be removed until
immediately, prior to testing or installation, as they also prevent the ingress of foreign matter, which could
harm the valve.
INSTALLATION
VALVE INLET: Under no circumstances should it be possible to isolate the safety valve from the protected
system. Safety valves should be mounted as close as possible to the protected system. The connecting pipe
should be straight and as short as possible. The inlet line to the safety valve should have an effective area of
flow, at least equal to that of the safety valve inlet. CompAir Limited should be consulted if the safety valve is
to be mounted in any position other than vertically. The maximum pressure drop through the inlet line to the
safety valve should not exceed 3% of the set pressure when the valve is discharging at its rated capacity.
VALVE OUTLET: No isolating devices shall be fitted to the outlet pipe. Discharge pipes should be as short
as possible and of such a size that the pressure developed therein not reduce the relieving capacity. Ensure
arrows indicating the direction of the flow are pointing in the correct direction. The cross-sectional area of
the discharge pipe should not be less than the area of the safety valve outlet. Where safety valves are
discharged into a manifold, the manifold must be capable of accommodating simultaneous discharge of all
valves connected to the manifold. Atmospheric discharge or discharge pipes should terminate at a location
which will not cause a hazard to personnel, particular attention being given to hazardous fluids or particles.
GENERAL: Inlet and outlet piping should be capable of supporting the safety, valve so that no unacceptable
mechanical load or vibration is transmitted to the valve, and be sufficiently strong to withstand 'the effects of
the reaction forces when the valve is discharging. All pipework or pressure vessels to which the safety valve
is connected should be thoroughly cleaned before fitting the safety valve, to ensure that foreign matter does
not pass through the valve. Particular care should be taken with the use of scaling compounds and P.T.F.E.
tape to ensure that they do not enter the valve.
Atmospheric discharge valves should not be painted or coated with any substance, which could possibly
obstruct or restrict free and full discharge through the valve. Suitable protection should be provided to
prevent environmental build up or ingress of foreign matter. Any condition that could lead to blockage of
discharge piping or discharge ports on safety valves must be avoided. Where appropriate, discharge pipes
should be provided to a non-hazardous location. Where there is a possibility of a liquid head forming in a
discharge pipe, a drain should be provided which leads to a safe discharge location. To prevent
unnecessary lifting of the safety valve it is recommended that there is a margin of at least 10% between the
maximum operating pressure and the set pressure of the safety valve.