Sliding vacuum pumps

The sliding-vane compressor is widely used as a vacuum pump as well as a compressor, with the largest volume approximately 6,000 cfm. The lower end of the volume range is 50 cfm. A single-stage compressor with atmospheric inlet pressure is limited to a 50 psi discharge pressure. In booster service, the smaller units can be used to approximately 400 psi. 

Vacuum breaker, 291 Vacuum pump, 9 Vacuum service, 10 ejectors in, 11 liquid pi.ston, 9 liquid piston, 130 sliding vane, 10 Valve design, 62 Valve loss, reciprocating, 62 Valve unloader, 81 Valve velocity, 62 Valves... 

Figure 6-39 illustrates a single-stage rotary vane vacuum pump, without external cooling jacket. The sliding vanes (No. 7 in illustration) are oiled by a closed system to aid... 

The sliding vane compressors and vacuum pumps have internal sliding vanes mounted longitudinally on an eccentric rotor in the body casing, Figures 12-114 and 12-115. 

Figure 8.35. The sliding vane rolary compressor and vacuum pump...

Sliding vane, rotary blowers and compressors 346 --------- vacuum pumps 365... 

Place the loaded rotor into the centrifuge chamber, attach the monochromator to its holder and close the sliding door. Start the vacuum pump and wait for the pressure to come down to 100 /im. 

An electrical resistance heater with more turns at the tube ends (to compensate for heat losses) surrounds each tube. There is a vertical laminar flow hood over the loading area to minimize particle contamination of the wafers being loaded. As we can see, there are temperature controls for the furnace tubes, and a power module to provide the electrical power. When operated as a LPCVD system, a unit including both the gas flow and vacuum systems is positioned on the right side. Such a unit is shown in Figure 8. Here we can see the vacuum pumps on the left, and the mass flow controllers on the right. The vacuum pump oil recirculation systems are shown in the slide out drawers. As can be seen in Figure 9, this system, as well as most current similar systems, operate under computer control. 

Step 6. Place disk on slide and insert into vacuum chamber used for spectral analysis. Close counting chamber and start vacuum pump. Count sample. Repeat with 2 other samples and blank. 

The pressure of the system was controlled to within 0.5 mm Hg for each series by a Cartesian diver manostat connected to a positive air leak, a vacuum pump, and a surge volume of 12 liters. An absolute mercury-in-glass manometer with a 0.1 mm sliding vernier was used to measure the pressure. Temperatures were monitored via two copper-constantan thermocouples one was located just above the liquid surface and the other just below it. Maximum differences of 0.4°C were detected, but an average of the two readings was reported to 0.2°C. Glacial acetic acid and acetone, both meeting ACS specifications, were used. 

Figure 6-5. Cross section of a sliding vane vacuum pump and how it operates.

Route piping from compressors or vacuum pumps which are prone to vibrate on supports independent of other process piping and use rests or sliding supports which provide some damping capacity rather than hangers. 

Figure 23. Vacuum plant with nonlubricated sliding vane vacuum pumps to reduce pollution of wastewater a) Reactor b) Precondenser c) Roots vacuum pump d) Intermediate condenser e) Sliding vane rotary pump (two stage) f) Final condenser g) Condensate collection vessel...

A rotary vane vacuum pump (Figure 5.5) is a rotating type of positive displacement vacuum pump in which an eccentrically suspended impeller slides tangentially past the inside wall of the stator (casing). Two or more vanes with the capability... 

Rotary vane pump A displacement pump where the compression occurs in a non-symmetric chamber being swept by a rotor having an oil-sealed sliding vane. See also Vacuum pump. 

Vacuum-lock inlet. An inlet through which a sample is first placed in a chamber the chamber is then pumped out, and a valve is opened so that the sample can be introduced to the mass spectrometer ion source. A vacuum-lock inlet commonly uses a direct-inlet probe, which passes through one or more sliding seals, although other kinds of vacuum-lock inlets are also used. 

In subsequent years, Savery made important improvements that benefited future steam inventions. In June 1699 he demonstrated to the Royal Society a pump with two receivers, each with a separate, hand-controlled steam supply. This ensured improved continuity of operation, allowing one receiver tn operate in its vacuum stage and the other under steam pressure. In 1701, he added two more critical steps a second boiler, avoiding the need to shut down the fire and pump, between stages and he replaced the two interconnected steam cocks with a single valve, run with a manually operated long lever. This may have been the inspiration for the modern slide valve and his inventiveness created, in effect, the world s first feed-water heater. 

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