An introduction to a dust collection rotary valve. Includes an overview of the applications they are ideally suited for, rotary valve construction, and the different options available.
What is a Rotary Valve?
Rotary valves (also known as airlocks, rotary feeders, or airlock feeders) are used to transition material from one pressurized point, such as a dust collector, to another unpressurized point, such as a drum or bin. Rotary valves help seal a pressurized system against loss of air and pressure. Rotary valves also help ensure loss of product during processing is minimized.
Rotary Valve Applications
Typical dust collection applications for rotary airlocks are dust collection, pneumatic conveying, pollution control, mixing, feeding, weighing, drying, and blending. Some of the relevant industries for rotary airlocks include metalworking , cement, minerals, agriculture, wood, paper, rubber, textiles, grains, paint, pharmaceutical manufacturing, and many more.
Typical Products for a Dust Collector Rotary Valve
- Baking Soda
- Corn or Corn Meal
- Grits (Corn)
- Oats (Rolled or Whole)
- Peanuts (Roasted)
- Soybean Flakes (Raw or Spent)
- Starch (Granulated or Powdered)
- Talcum Powder
- Tobacco (Ground)
- Woodworking or paper pulp
- And more
Rotary Valve Construction
The main parts of a rotary valve comprise of the following:
- Motor (Can come in various combinations for a multitude of applications and environments. For example; speeds, explosion/spark proof, chain driven vs. direct driven, and more.
- Drive, reducer or gear box which takes speed and converts it into power
Rotary Valve Options
Depending on your industry, application, and environment there are a few rotary valve options that could work for your facility. Here are some of those options in further detail:
- High Temperature: Can expand when exposure to high heat. The rotary valves vanes are also shortened to leave a gap between the vanes and housing.
- Low Temperature: Should be used or low or regular temp
- Vanes: Standard is 6 vanes but 8 vanes can be made available, but would be more time and cost consuming.
- Size: Sizes can vary from 6, 8, 10, 12, 14 and larger depending on application
- Shape – Square or Round
- Duty: Heavy duty or regular duty
- Cast Iron (standard)
- 304 Stainless Steel (resistant to most chemicals)
- 316 Stainless Steel (resistant to chemicals 304 stainless steel can’t handle)
- Chrome Plated Cast Iron (harder than steel, best for abrasive material)
- Beveled Steel Tips (standard – beveled spins counter clockwise so as not to compact the material and bind the vanes)
- Replaceable Steel Edge – (good for applications that vary in their process)
- Urethane Tips (best for large particles that may wedge between the vanes)
- Rotor: Open or Closed