Rotary valve and airlock rebuilding for dry product plants
We rebuild aerolocks and rotary valves for dry product and food plants. The rebuild restores the housing bore, the rotor, the end plates and the shaft fits that control how well the valve meters product and holds air.
- Built from your specifications, drawings or samples
- Free consultations, prompt estimates
- Wolf Machine stands behind the work we perform
- Reno shop, Monday to Friday, 7:00 am to 3:30 pm
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A rotary valve sits under a hopper, cyclone or filter and lets powder or pellets drop through while the pressure above and below stays separate. It only works while the rotor and its housing stay close together. We rebuild aerolocks and rotary valves for dry product and food plants.
At a glance
- Aerolock and rotary valve rebuilding
- Housing bore, rotor tips and end plates
- Shafts and bearing fits
- Stainless and steel valves
I have used Wolf Machine several times over the past few years for fabricating and repair of parts on my ultralight aircraft. [...] These guys are great to deal with. I wouldn't take my projects anywhere else.
Why clearance is the whole story
Inside the valve, a bladed rotor turns in a closed housing. The gap between the rotor tips and the housing wall is small on purpose. As the gap opens, air leaks backward through the valve, product bridges, and the plant's conveying or dust collection stops pulling as it should.
Abrasive product wears the tips and the bore. Bearings that wear let the rotor drop and scrape one side of the bore. Both end with the same symptom: more air getting through and less product.
Signs a valve needs a rebuild
The usual signs are falling vacuum or pressure on the line, product blowing back up, a valve motor drawing more current, and shiny score marks inside the housing when it is opened.
- Air leaking past the rotor
- Metal scoring on the bore or end plates
- Rotor tips that look rounded or short
- Shaft seals that leak product
How the rebuild goes
The valve is stripped and the housing is measured. A worn bore is built up and machined round and to size, and rotor tips are built up and trimmed to run at a close gap. End plates are faced flat and the bearing seats are brought back, with shaft journals rebuilt by metal spray where they have worn.
Food and dry product plants often run stainless valves. Stainless welding and stainless machining are part of the same shop, and the material page for stainless steel covers what to tell us about the grade.
Why plants rebuild instead of replace
A rotary valve is bolted into a line, sized for the product and often fitted with a specific drive. Rebuilding the housing and rotor keeps the valve you already have in the same place, with the same flange pattern and the same motor. That is why dry product and food plants send the valve in for rebuilding and keep the line as it is.
What to send
Valve make and size, the product it meters, the material of the housing and photos of the bore and rotor. Call (775) 359-5570 or attach them to the quote request.
Sources
- Wolf Machine & Fabrication services list (2026-10-18)
- Rotary feeder (Wikipedia) (2026-10-18)
What gets rebuilt
- Housing bores scored by product or worn by the rotor tips
- Rotor vanes and tips worn short
- End plates and faces that no longer seal
- Shaft journals and seal areas
- Bearing housings in the end plates
Typical parts
- Valve housings
- Rotors
- End plates
- Shafts
How to send us the job
Send a drawing (PDF, DWG, DXF, STEP or IGES), a sketch with sizes, or photos of the part with a tape or scale in the shot. A sample works too: bring it to the shop.
Related
Questions about this service
From the shop
Work from the shop
Straight answers
Rotary valve and airlock rebuilding questions
Still have a question? Call (775) 359-5570, Monday to Friday, 7:00 am to 3:30 pm.
Do you rebuild food plant valves?
Yes. We rebuild aerolocks and rotary valves for dry product and food plants. Tell us the housing material when you send photos.
Can you make a replacement rotor?
Yes. We machine and fabricate new parts from a sample or drawing when a rotor is too worn to rebuild.
Send us the job
Request a quote
Tell us what you need, attach a drawing or photos of the part, and we will get back to you during shop hours. Free consultations; prompt estimates.
- From your specifications, drawings or samples. We can also assist you in designing your product or part.
- Free consultations and prompt estimates
- Stands behind the work: Our rates are very competitive and our quality is second-to-none. Wolf Machine stands behind the work we perform.
- Company accounts: all major credit cards, or we can open an account for your company
Shop hours Monday to Friday, 7:00 am to 3:30 pm. Send your request any time and we will get back to you during shop hours.
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