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Rough vacuum range

The majority of industrial chemical and petrochemical plants vacuum operations are in the range of 100 microns to 760 torn This is practically speaking the rough vacuum range noted above. For reference ... [Pg.129]

This will be found almost exclusively in the rough vacuum range. The character of this type of flow is determined by the interaction of the molecules. Consequently Internal friction, the viscosity of the flowing substance. Is a major factor. If vortex motion appears In the streaming process, one speaks of turbulent flow. If various layers of the flowing medium slide one over the other, then the term laminar flow or layer flux may be applied. [Pg.15]

Measurement of pressures in the rough vacuum range can be carried out relatively precisely by means of vacuum gauges with direct pressure measurement. Measurement of lower pressures, on the other hand, is almost always subject to a number of fundamental errors that limit the measuring accuracy right from the start so that it is not comparable at all to... [Pg.76]

U-tube vacuum gauges fiiied with mercury are the simpiest and most exact instruments for measuring pressure in the rough vacuum range (1013 to a... [Pg.79]

Leak Detection on Systems in the Rough Vacuum Range... [Pg.180]

For the connection of leak detectors to systems operating in the rough vacuum range there are several possibUities with specific advantages and disadvantages. [Pg.180]

Fig. 9.7 Nomogram for determination of pump-down time tp of a vessei in the rough vacuum pressure range... Fig. 9.7 Nomogram for determination of pump-down time tp of a vessei in the rough vacuum pressure range...
N cuum technology acceptance specifications for rotary piston vacuum pumps Part 1 - Rotary piston and vane type rotary vacuum pumps in rough and medium vacuum range Part 2 - Roots vacuum pumps in medium vacuum range ... [Pg.179]

This chapter is primarily devoted to pumps for high vacuum-operation (10 3-10 5 torr), which is the vacuum range of greatest interest in chemical vacuum lines. In addition, rough-vacuum systems (760-0.1 torr) are discussed in connection with their use in manipulating mercury-filled apparatus, such as Toepler pumps and McLeod gauges. [Pg.65]

VACUUM PUMPS (ROUGH-MEDIUM VACUUM RANGE) 3.2.1 Oil-sealed Rotary Pumps... [Pg.57]

Such pumps are gas-transfer pumps. They are used extensively both to back high-vacuum pumps and to act as devices for achieving pressures in the rough-medium range in activities such as distillation, drying, etc. [Pg.57]

Chapter 3 summarised initially the various types of vacuum pump available and the pressure ranges in which they normally operate. Subsequent sections dealt specifically with types of pump and, in some cases, to support calculations, reviewed the operating principles and characteristics. For example, aspects of oil-sealed rotary pump operation were discussed (Examples 3.1-3.5) and Roots pumps, widely used in applications where large gas loads at pressures in the rough-medium range have to be handled, were examined (Examples 3.7-3.9). [Pg.220]

The mechanical phenomena gauges measure the actual force exerted by the gas. They include a U-tube, a capsule dial, a strain, a capacitance manometer, a McLeod gauge, etc. Vacuum is measured according to the displacement of an elastic material or by measuring the force required to compensate its displacement. The measurement ranges from atmospheric pressure to 102 Pa in rough vacuum conditions. [Pg.51]

The flow conditions within a gas can be described through the Knudsen number. Flows through pipes are characterised through the Reynolds number. At relatively high pressures in a rough vacuum, a viscous flow is present which may either be laminar or turbulent. For a viscous flow, a mutual influence between the flowing particles is typical. In the turbulent range, the molecules behave chaotically. The Knudsen number is defined as follows ... [Pg.7]

The areas of application for these vacuum pumps are all within the rough and medium vacuum range, the principal vacuum range for chemistry processes. Only the short path and molecular distillation processes rely also high-vacuum pumps like the diffusion pump or even the turbomolecular pump (kinetic gas pumps). High-vacuum pumps are not covered in this book. For these refer to [2, 3]. [Pg.12]

The pumping speed S of a vacuum pump operating in the rough and medium vacuum range is commonly stated in m h . ... [Pg.12]

Coarse vacuum (vacuum technology) A vacuum in the range of atmospheric to about 10 Torr. Also called a rough vacuum (preferred). See also Rough vacuum. [Pg.582]

Vacuum, medium The pressure range between rough vacuum and high vacuum. [Pg.720]

See other pages where Rough vacuum range is mentioned: [Pg.378]    [Pg.16]    [Pg.29]    [Pg.82]    [Pg.378]    [Pg.64]    [Pg.103]    [Pg.97]    [Pg.121]    [Pg.180]    [Pg.690]    [Pg.378]    [Pg.16]    [Pg.29]    [Pg.82]    [Pg.378]    [Pg.64]    [Pg.103]    [Pg.97]    [Pg.121]    [Pg.180]    [Pg.690]    [Pg.343]    [Pg.343]    [Pg.11]    [Pg.16]    [Pg.139]    [Pg.597]    [Pg.200]    [Pg.189]    [Pg.51]    [Pg.116]    [Pg.82]    [Pg.241]    [Pg.407]    [Pg.597]    [Pg.655]    [Pg.1119]   
See also in sourсe #XX -- [ Pg.2 , Pg.57 ]



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