• A.

    Rotary valves can be very effective at minimizing leakage when properly configured by an expert.

    As a general recommendation to prevent dust leakage, valves should be equipped with ACST-4 shaft seals and an outboard bearing design. You should also check rotor-to-housing tolerances often, as enlarged tolerances can also cause leaks.

    Relevant for: Conveying Systems, NFPA, Safety
  • A.

    The most common parts you need to replace on a regular basis include the rotor, shaft seals, and bearings. It’s a great idea to keep spare parts for your rotary valve. We have an NFPA compliance kit you can order to have the most important parts on your shelf just in case you need to make a quick replacement.

    Relevant for: Technical Support, NFPA
  • A.

    Rotor-to-housing tolerances, or clearances, are the distance between your rotor tips and valve housing. Because they wear down over time, you should measure them as part of your regular maintenance routine. Increased tolerances leave a bigger gap for material to leak through, which prevents the valve from working effectively. This can lead to issues with material flow, NFPA compliance and safety, and overall efficiency. Check them often!

    Relevant for: NFPA, Safety
  • A.

    Too much clearance between the rotor, endplates and or housing can result in air loss. Measure the rotor to endplate and rotor to housing clearances to confirm that they are an NFPA compliant 0.0079 inches. If the clearance is larger than this, it might be time to replace your rotor, rotary valve, or have it sent back to ACS for a repair or evaluation. Make sure to stick to a maintenance schedule and check your clearances at least every three months.