Translate the sentences. Pay attention to the words in italics.

Combustion inlet part scroll wobble-plate

Centrifugal impeller rotary screw via

Contaminate housing rim vane

Casing handle remediation turbine

Blade diffuser reduce stationary

Attainable diaphragm reciprocating stage

Axis crankshaft radial similar to

Axial-flow compressor mesh shaft

Words to be remembered.

Unit VI. Pumps and Compressors

Make notes under the following headings. Then use your notes to talk about it.

Follow-up Activities

Pump Types

Dry Pumps (non-lubricated) provide a clean vacuum over the entire vacuum range. Dry pumps require little maintenance and don't generate any waste material.

Water-Lubricated Pumps provide a rough vacuum at low initial cost and are very simple to operate. These pumps are corrosion resistant but are not suitable for water vapor sensitive systems.

Oil-Lubricated Pumps offer high capacities, high vacuum/pressure levels, and lower noise levels. Diffusion pumps feature an ultra-high vacuum. Oil-lubricated pumps, however, require routine maintenance and oil changes, and the oil may contaminate your vacuum.

To determine which pump is right for your application, calculate your free-air capacity by adding up the free-air requirements for all air-powered instruments. Add an additional 25% to allow for system variables and to provide capacity for future needs. Then determine the maximum vacuum or pressure required for your application – see the “Vacuum/Pressure Conversion Table” below for any necessary values.

1. Vacuum Pump History.

2. Vacuum Pump Classification.

3. Vacuum Pump Applications.

4. Vacuum Pump Accessories.

5. Vacuum Pump Repair.

6. Some Vacuum Pumps’ Benefits and Features.

Before you start: Think it over. Agree-Disagree

“First, be sure a thing is wanted or needed, then go ahead.” Thomas Edison.

“Wonders are many, and nothing is more wonderful than man.” Sophocles. Note: Sophocles, 495–406, Greek Dramatist

Reading, Vocabulary & Creative Practice

1.The Earth rotates about an axis between the North Pole and the South Pole.

2.In vacuumservice, the attainable pressure reduction is limited.

3.A propeller, an oar, a compressor have blades.

4.The contaminated ground water is drawn from wellsby vacuum.

5. Centrifugal force is opposite centripetal.

6. Compressor is a part of a machine for compressing gas or air.

7.A force of collision impels an object along its path.

8.The teeth on these two wheels mesh as the teeth revolve.

9.This mechanical device increases the pressureof a gas by reducing its volume.

10.Compressors are similar to pumps.

11.My opinion is similar to yours.

12.A stationary target is easier to aim.

13.There is a big difference between the words “ stationary ” and “stationery”.

14. Vane is a bladelike part of certain machines, which has a flat surface.

15.I sent a present to my friend via her sister.

16. Wobble-plate compressormeans “компрессор с качающей шайбой”.

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