DeLUX MOISTURE Link G2 DP, Руководство по эксплуатации

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100 RegO Dr. P.O. Box 247 Elon, NC 27244 USA www.regoproducts.com Phone (336) 449-7707 Fax (336) 449-6594
RegO® Pressure Relief Valves
Ordering RegO® Pressure Relief Valves
When ordering RegO® Pressure Relief Valves, be sure you are
certain that it will sufficiently protect the container as specified in
the forewording information, NFPA Pamphlet #58 and any other
applicable standards or specifications.
All adapters, protective caps and deflectors must be ordered
separately, unless specified otherwise.
Part Number Explanation
Products carrying an “A” or “AA” prefix contain no brass parts and
are suitable for NH3. Hydrostatic relief valves carrying an “SS”
prefix are of stainless steel construction and are suitable for use
with NH3. The products are also suitable for use with LP-Gas
service except relief valves carrying an “AA” prefix. These are
of partial aluminum construction and are listed by U.L. for NH3
service only.
Safety Information - Relief Valves Don’t Last Forever
RegO® Relief Valve for lift truck containers
The internal spring is protected from external
contamination but the other external parts must
be protected with a cap. Circular rubber seat
disc ring seats on brass shoulder approximately
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This article was prepared by the engineers of RegO® products,
after technical consultation with valve manufacturers and other
industry sources. Its purpose is to alert and remind the LP-Gas
industry of the importance of proper maintenance of pressure
relief valves. It applies most particularly to separate relief valves
with emphasis on lift truck and motor fuel containers where the
hazards of contamination are greatest.
Since the beginning of our industry, manufacturers of equipment
and distributors of LP-Gas have worked diligently to provide a safe
environment for employees and consumers. The history of the
industry testifies to the success of their efforts.
But the industry is now entering its sixth decade and equipment
installed years ago is failing because of age. Every year, additional
equipment will fail unless it is replaced. Pressure relief valves are
no exception. The valve manufacturers and LP-Gas dealers are
naturally concerned about this situation.
Relief valves, over the years, may not function properly
in several ways:
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They may leak at pressures below the set pressure.
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They may open and fail to properly reseat.
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They may open at higher than the set pressure.
Causes of Relief Valve Failure
A relief valve is designed to have a safe useful life of many years,
but that life will vary greatly depending on the environment in
which it “lives.” To attempt to estimate the safe useful life of a relief
valve and the effect of environment on its performance, a brief
discussion of the materials used and the nature of its performance
should be helpful.
Relief valve bodies are generally made of brass or steel. Springs
are made from various spring wires which are plated or painted,
or made of stainless steel. Valve seat discs are made of synthetic
rubber compounds which will remain serviceable in an atmosphere
of LP-Gas. Relief valve stems, guides, etc. are generally made
from brass or stainless steel.
These failures to function properly are due primarily to
four “environmental’’ conditions:
1. Corrosion of metal parts (particularly springs) which result
in the component parts failing to perform.
2. Deterioration of the synthetic rubber seat disc material.
3. Clogging or “cementing” of the movable relief valve
components so that their movement is restricted.
4. Debris on the valve seat after the relief valve opens,
effectively preventing the valve from reseating.
Corrosion is caused by water, corrosive atmospheres of salt and
industrial pollutants, chemicals, and roadway contaminants. High
concentrations can attack the metal parts vigorously. No suitable
metals are totally resistant to such corrosion.
Synthetic rubber and seat disc materials can also be attacked by
impurities in the gas and corrosive atmospheres, particularly those
with sulphur dioxide. There are no suitable rubber materials which
resist all contaminants.
“Cementing” of relief valve parts has been caused by normal
industrial atmospheres containing particles of dirt, iron oxide,
metal chips, etc. combined with water, oil, or grease. Ice collecting
in recessed valves could cause relief valves to fail to open. Paint
and tar in relief valves also cause failure to function properly.
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