Questions about rotary valve manufacturing, troubleshooting, compliance, and more
The rotary valve geniuses at ACS Valves love to help manufacturers with their conveying queries, conundrums, and challenges. Browse our collection of questions and answers here.
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Corrosive materials can damage the rotary valve’s internal parts over time, including the rotor-to-housing tolerances. We recommend a coating called XTR-Coat to minimize the effects of acidic, abrasive, or corrosive materials. Its durability prolongs the lifespan of your valve and parts, and its compliance with FDA and USDA regulations also makes it an excellent choice in many food-grade applications.
Whether you’re conveying ingredients for medicated pet foods, kibble with allergen control, or any pet food that must adhere to strict food safety guidelines, it’s important to prevent cross-contamination between batches. Make sure your valve is designed with outboard bearings and reliable shaft seals that are easy to replace.
To quickly wipe away residual product that may harbor bacteria, choose a Quick-Clean design, which allows you to open up the valve without tools for fast and easy cleaning. You might also consider sanitary materials and coatings, such as stainless-steel and XTR-Coat.
We have lots, and they depend on your application. One approach is coatings, like hard chrome or the abrasion resistant XTR-Coat, which can help material slide through the valve without sticking.
Before we make this answer too complicated, check out our blog on material flow tips.
You know what they say about squeaky wheels! It’s possible your rotor needs replacing: in our experience, the culprit is usually decreased rotor clearances.
It’s possible you’re also dealing with a mechanical problem with the drive chain or drive shaft, or some kind of foreign object is jammed inside.
Check your rotary valve maintenance manual for help with troubleshooting and repair.
Sometimes the rotation of the rotor is reduced due to an overload of material, or larger pieces of material being fed through the valve, jamming in the clearances. In this case, shear pin sprockets will shear the pin on the sprocket, reducing the risk of damage to the rotor.
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.
The capped pipe is called a housing vent port. Rotor pockets can sometimes contain a volume of pressured air, which can impede material flow into the airlock inlet, reducing your efficiency. Also, in conveying systems that run at 6 PSI and higher, large releases of air up the return side of the airlock can cause pulsing in the material flow into the conveying line. Using a vent helps solve both of these issues, and is also helpful in improving your fill efficiency.
Shear protectors reduce the flow of material at the valve's inlet. Reduced flow allows for better pocket fill and also reduces the risk of product jams in your housing clearances–ultimately protecting your product from damage.
