Gardner Denver WELCH CRVpro Series, Руководство по эксплуатации

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Description
10 P1700040
This state of equilibrium is referred to as the ultimate pressure or blank off pressure of the pump and
its system. No matter how much additional pumping time is provided, no further reduction in system
pressure will be accomplished once ultimate pressure is attained.
Intake Anti-suck back Protection
When power to the pump is turned off, this device closes automatically, maintaining vacuum in the
system being evacuated, and vents the inside of the pump to atmospheric pressure.
3.4.4 Oil Functions
WARNING!
Vacuum pump is shipped without oil inside to prevent possible spillage during
shipment. Oil must be added prior to use!
The oil fulfils the following functions in the vacuum pump:

lubricating the sliding parts, such as rotor, vane, radial shaft seals

sealing the moving parts against the stator wall to reduce leaks

conducting the heat of compression to the metal walls (cooling)
The oil transports the polluted particles and corrosive media and thus effects continuous cleaning of
the internal surfaces.
3.4.5 Pump Lubrication
To ensure efficient operation and proper maintenance, and to minimize noise and oil vapours, it is
important to use the correct type and quantity of oil. Directorr
™ Premium vacuum oil has been
especially developed to have the proper viscosity, low vapour pressure, and chemical stability needed
to produce peak pumping efficiency. The ultimate vacuum guarantee on Welch pumps applies only
when this oil is used. Each pump is supplied with sufficient oil for filling. Additional oil is available. See
chapter 8 Overview of Accessories.
3.4.6 Exhaust Filter
Any oil-sealed vacuum pump tends to discharge oil mist from its exhaust port when the pump operates
under high-
flow conditions, such as when the pump’s intake is at or near atmospheric pressure.
Typically, oil mist in the form of a white puff of “smoke” can be seen from the exhaust port when no
filter is used. Once the vacuum level and the corresponding air flow through the pump are reduced,
very little, if any, oil mist will be emitted. An exhaust filter is recommended for any vacuum pump
installation where the pump operates at high intake pressures for a prolonged period of time. Oil
droplets entrained in the pump’s exhaust are removed by the exhaust filter element. Use of an exhaust
filter typically reduces or baffles pump noise as well. Exhaust filters are sometimes referred to as oil
mist eliminators. See chapter 8 Overview of Accessories.
3.4.7 Gas Ballast
Condensates could have collected in the vacuum pump if:

the vacuum pump is new

it has not been used for long periods

the pump's maximum tolerance of water vapour pressure has been exceeded