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45 Cards in this Set
- Front
- Back
Pick either increases or decreases for the four spaces |
Fluids |
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There must be a ______ ________ to make a fluid flow |
Pressure difference |
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Gas always flows from ______ pressure to ______ pressure. |
High pressure to low pressure |
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Are liquids considered compressible or incompressible? |
Incompressible |
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Zero degrees kelvin is equal to _______°C |
-273°C (negative) --> one degree change on the Kelvin scale is equal to one degree change on the Celsius scale |
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Zero degrees Rankine is equal to _____°F |
-459°F (negative) --> 1° Rankine is equal to 1° Fahrenheit |
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Atmospheric pressure at sea level is equal to _____ psia |
14.7 psia |
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Gases expand to fill any container until .... |
Pressures equalize |
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What are the 3 ways to increase pressure in a sealed container? |
1) reduce the volume 2) heat the gas 3) pack more gas into the confined space |
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Why does heating gas create a higher pressure? |
The molecules move faster and hit the surface more often with greater force |
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A positive displacement compressor is a .... |
Sealed container in which pressure is created on the inside surface by molecules of gas striking the surface and creating force (think of a cylinder tube and piston) |
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What is the law of conservation of energy? |
Energy can neither created nor destroyed, but the state can be changed |
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Calculations for compressors use _______ scales to measure temperature and pressure. |
Absolute scales |
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Absolute scales begin at _____ and move in ..... |
They begin at zero and move in only a positive direction |
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What happens at the absolute zero of temperature or pressure? |
- at absolute 0 temperature all molecular action in gas stops - absolute 0 on a pressure scale indicates a perfect vacuum or the absence of all pressure |
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What are the two absolute scales for temperature? Which one pairs with Celsius? |
1) Kelvin: which has the same magnitude as degrees Celsius.
2) Rankine: which has the same magnitude as degrees Fahrenheit |
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1 psia = ____ kPa |
6.9 kPa |
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Atmospheric pressure at sea level is equal to _____ bar |
1.01 bar |
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What is considered the standard temperature? |
20°C |
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Do hue age pressure reading usually account for pressure of the atmosphere? |
No |
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Three common devices for measuring pressure are |
1) barometer 2) manometer 3) bourdon tube |
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What is Boyle's law? |
It is a gas law only.
If the temperature remains constant, the volume will change inversely to the pressure
V1 X P1=V2 X P2 |
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What is Charles law? |
It states that, if the the pressure on a given gas is held constant, the volume will change in direct proportion to the absolute temperature |
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What is guy-lussacs law? |
If the volume is constant, the pressure exerted by the gas is directly proportional to the absolute temperature
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What is the combined gas law? |
A combination of the laws from Boyle, Charles, and gay-lussac |
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What are the effects of altitude on a compressor? |
An increase in altitude causes a decrease in atmospheric pressure. With a compressor, this decrease in intake pressure causes a decrease in power requirements. Because the air is less dense, there is also not as much compressed air delivered in the same time period as there would be at sea level |
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Why type of compressor is this? |
Diaphragm compressor |
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Why type of compressor is this? |
Integral compressor |
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What is a labyrinth compressor? |
Labyrinth compressors have a special design that allow them to run without oil. The series of labyrinths cause the pressure to drop until there is acceptable leakage. It uses less power to operate |
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What is a diaphragm compressor? |
Diaphragm compressors are suitable where oil free air is needed such as the food industry. The crankshaft and con rod action is the same, but the con Rod attaches to a flexible membrane or diaphragm. This membrane creates a barrier between the lubricating oil and the compression area. They are not made for high intensity work |
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What is an integral compressor? |
It is common in natural gas compression stations. It is an engine and a compressor combined into one frame with one common crankshaft. The engine provides the driving power to turn the crankshaft,while the compressor piston takes the power from the same crankshaft to compress the gas |
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What type of compressor is this? |
A single acting reciprocating compressor |
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What are the two main categories of compressors and their sub divisions? |
1) non positive displacement --> dynamic 2) positive displacement --> rotary --> reciprocating |
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What is the basic principle of a positive displacement compressor? |
Positive displacement compressors work on the principle of trapping a specific volume of air and then reducing the volume to get a higher pressure |
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Why type of compressor is this? |
Labyrinth compressor |
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Why type of compressor is this? |
Diaphragm compressor |
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Why type of compressor is this? |
Integral compressor |
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What is a labyrinth compressor? |
Labyrinth compressors have a special design that allows them to run without oil (so it is good for places that can't have oil in the air). The series of labyrinths cause the pressure to drop until there is acceptable leakage. It uses less power to operate |
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On a double acting compressor how many compressions are there per rotation of the crankshaft? |
2 |
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Why type of compressor is this? |
Labyrinth compressor |
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What is this method retrieving oil called? |
Gas injection |
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What is this method retrieving oil called? |
Gas lift: gas is injected into the well, it passes through a series of lift valves pushing the oil out of the well |
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Atmospheric pressure at sea level is equal to how many of each of the following? 1) _______ bar 2)________ psi 3)________ kPa |
1.01bar 14.7 psi 101.4 kPa |
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Compressed air operates in much the same manner as oil in a hydraulic system except for two major differences. What are they? |
1) gases are compressible 2) gases expand to fill any container |
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Card # 45 |
Complete set |
