--- title: Rotary Valve and Airlock Rebuilding | Wolf Machine Reno url: https://wolfmachinenv.com/services/rotary-valve-and-airlock-rebuilding/ business: Wolf Machine & Fabrication, Inc. address: 4812 Longley Ln, Reno, NV 89502 phone: (775) 359-5570 hours: Shop Monday-Friday 7:00 am-3:30 pm; closed Saturday and Sunday type: Metal and plastic fabrication and machining (custom and CNC machining, welding, metal and plastic fabrication, gearbox and part repair, align boring, metal spray) --- [Photo: Stock photo: a milling cutter taking a finishing pass on a steel block, coolant line beside it] - [Home](https://wolfmachinenv.com/) - [Services](https://wolfmachinenv.com/services/) - Rotary valve and airlock rebuilding # 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. Stock photo: a milling cutter taking a finishing pass on a steel block, coolant line beside it 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. James B. ยท Google review, September 2023 [Leave us a Google review](https://search.google.com/local/writereview?placeid=ChIJVWVOfCI_mYARibcFMPsDEKc) ## 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](https://wolfmachinenv.com/services/metal-spray/) where they have worn. Food and dry product plants often run stainless valves. [Stainless welding](https://wolfmachinenv.com/services/stainless-steel-welding/) and stainless machining are part of the same shop, and the material page for [stainless steel](https://wolfmachinenv.com/materials/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](tel:(775)%20359-5570) or attach them to the quote request. ### Sources - [Wolf Machine & Fabrication services list](https://wolfmachinenv.com/services/) (2026-10-18) - [Rotary feeder (Wikipedia)](https://en.wikipedia.org/wiki/Rotary_feeder) (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 ### Materials [Steels and steel alloys](https://wolfmachinenv.com/materials/steel-and-steel-alloys/) [Stainless steel](https://wolfmachinenv.com/materials/stainless-steel/) [All materials we machine](https://wolfmachinenv.com/materials/) ### 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. [Request a quote](#quote) [What to put on a drawing](https://wolfmachinenv.com/guides/what-to-put-on-a-drawing/) ### Talk to the shop [(775) 359-5570](tel:(775)%20359-5570) | Monday to Friday | 7:00 am - 3:30 pm | |---|---| | Saturday and Sunday | Closed | [Request a quote](#quote) ### Related - [Food processing and dry product plants](https://wolfmachinenv.com/industries/food-and-dry-product-plants/) - [Stainless steel welding](https://wolfmachinenv.com/services/stainless-steel-welding/) - [Metal spray](https://wolfmachinenv.com/services/metal-spray/) - [Stainless steel](https://wolfmachinenv.com/materials/stainless-steel/) - [Part design and parts made from samples](https://wolfmachinenv.com/services/part-design-from-samples/) ### Questions about this service - [Is metal spray as strong as new metal?](https://wolfmachinenv.com/faq/is-metal-spray-as-strong-as-new-metal/) ## Work from the shop [Photo: A grinder assembly: machined cutter housing between thick plate end flanges, coupled to an electric motor on a fabricated base] Job 02 A grinder assembly: machined cutter housing between thick plate end flanges, coupled to an electric motor on a fabricated base. [Photo: An inline grinder unit: bolted cutter housing with threaded ports, coupled to its electric motor on a steel base] Job 03 An inline grinder unit: bolted cutter housing with threaded ports, coupled to its electric motor on a steel base. [Photo: An industrial gearbox housing (speed reducer)] Job 11 An industrial gearbox housing (speed reducer). [See all our work](https://wolfmachinenv.com/gallery/) ## Related services - [Gearbox repair and rebuilding](https://wolfmachinenv.com/services/gearbox-repair/) - [Hydraulic cylinder repair](https://wolfmachinenv.com/services/hydraulic-cylinder-repair/) - [Pump, shaft and turbine repair](https://wolfmachinenv.com/services/pump-and-turbine-repair/) - [Electric motor shaft and endbell repair](https://wolfmachinenv.com/services/electric-motor-shaft-and-endbell-repair/) - [Rock crusher and screen parts repair](https://wolfmachinenv.com/services/crusher-and-screen-parts-repair/) - [Metal spray](https://wolfmachinenv.com/services/metal-spray/) ## Rotary valve and airlock rebuilding questions Still have a question? Call [(775) 359-5570](tel:(775)%20359-5570), 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. [Photo: Stock photo: a lathe turning a bar, hot chips flying] ## 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. [Call (775) 359-5570](tel:(775)%20359-5570) - 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. Stock photo: a lathe turning a bar, hot chips flying