At the end of this module, you will be able to:
- List safety hazards and safety guidelines associated with vacuum pumps, vacuum blowers, and steam ejectors
- Explain how liquid ring vacuum pumps create vacuum
- Explain why vacuum pump seal water should be cool
- Identify and describe the main components of liquid ring vacuum pumps, centrifugal blowers, and steam ejectors
- Identify and describe key process flows for a liquid ring vacuum pump
- Describe the operation of liquid-ring vacuum pumps, centrifugal blowers, and steam ejectors
The following key questions are answered in this module:
How is the seal water used in liquid-ring vacuum pumps?
It seals in the pumping chambers and it also cools the incoming air
Why is it important for vacuum pump seal water to be cool?
It helps cool the incoming air, which increases its density and the vacuum level produced. It also helps avoid vaporization inside the pumps, which would reduce capacity and efficiency
How is vacuum used on a paper machine?
To help dewater the stock in the forming section, to dewater and clean the felts in the press section, and to help transfer the sheet between sections
What is the difference between a centrifugal fan and a centrifugal blower?
The American Society of Mechanical Engineers uses the "specific ratio" - the ratio of discharge pressure over suction pressure. Fans have a specific ratio up to 1.11, while blowers have specific ratios of 1.11 to 1.20.
Is a thermocompressor a type of steam ejector?
Yes. A thermocompressor is a steam ejector whose purpose is to recover the latent heat content of low pressure steam.
Below is a transcript of the video sample provided for this module:
Single stage blowers are constant speed, rotating machines. Air flows through single stage blowers are controlled by guide veins, either by a single set of inlet guide veins or by two sets of guide veins. A dual vein, single stage blower, uses two sets of veins, one on the inlet side and one on the outlet side. So they cost a bit more initially, but this design is more efficient. The outlet guide veins are used to control the aerodynamic shape or flow pattern of air as it is released from the tip of the impeller. So they control the air flow through the blower.
Use the additional resources and links below to learn more about this topic: