OMB Valves S.p.A
. Forged steel GATE, GLOBE & CHECK Valves Installation, Operation and Maintenance Manual Rev.5- 2016
Via Europa,7 Cenate Sotto 24069 (BG) Italy
Tel: +39 035 4256711
Fax: +39 035 942638
www.ombvalves.com
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If system testing will subject the valve to a pressure in excess of its working pressure rating , then the intended
testing pressure and a statement explaining whether the test pressure is through the opened valve or a differential
across the closed valve, should be noticed to OMB in advance at the time of purchasing.
Note:
Ask OMB Customercare for valves pressure/temperature rating.
3.
FIRE SAFETY
All metal-to-metal seat OMB gate, globe and check valves are inherently fire-safe design and come standard with
graphite packing and gasket.
Note:
Customer should indicate on their purchasing order when requires fire-safe design.
4.
THROTTLING SERVICE
Valves used to control the rate of fluid flow subject to severe fluid turbulence, which can have the effect of creating
a high-energy conversion within the valve and piping system. This energy conversion is usually indicated by high
noise levels. The possibility exists for mechanical damage to the valve and piping system.
OMB S.p.A
should be
consulted on proper valve selection for throttling applications.
5. TEMPERATURE CHANGES
Forged steel expands with rising temperatures and contracts with falling temperatures. In general, increasing
temperature causes a decrease of mechanical strength, which is regained on return to a lower temperature. A
condition of non-uniform temperature in a structure may cause significant thermal stresses or distortion with
possible adverse effect on valve performance.
6. TRAPPED PRESSURE
When a closed valve containing liquid is heated (e.g., from process Condition, radiation or solar heating) the cavity
pressure will increase due to volumetric expansion or vaporization of the liquid. Conversely, cooling an un-drained
cavity below the freezing point may also result in volumetric expansion of the media. These expansions can result
in extremely high pressures occurring in the valve.
7. MATERIAL COMPATIBILITY
It is important that Forged steel valves and lubricants be chemically compatible with the other piping system
components, line fluids and the environment. Guidance should be obtained from
OMB Customercare Service
whenever there appears to be reason for such concern.
