Name: Rotary Valve
Brand: CYprocess
Availability: InStock

Question 1

What is the difference between drop-through and blow-through rotary valves?

Accepted Answer

A drop-through valve discharges by gravity into a hopper, chute or screw, and is used under silos, filters and vacuum receivers. A blow-through valve feeds product directly into a positive-pressure pipeline, so it becomes the injection point of the pneumatic system.

Question 2

When is a quick-clean design preferred?

Accepted Answer

Where the valve is opened frequently for wash-down or product changeover, typically in food, pharmaceutical and multi-recipe plants. Slide-rail or quick-open end covers let the rotor be withdrawn without disturbing the drive, which shortens cleaning downtime considerably.

Question 3

What is the difference between internal and outboard bearings?

Accepted Answer

Internal bearings keep the assembly compact but sit closer to the product and the process temperature. Outboard bearings move them outside the housing, which suits high-temperature service and fine powders because the bearings stay clean and cooler.

Question 4

How is rotary valve capacity estimated?

Accepted Answer

Approximately from pocket volume, rotor speed, fill efficiency, bulk density and a duty factor. The formula gives a starting point only, because differential pressure, temperature and particle size also affect real throughput, so final selection is confirmed against the duty.

Question 5

How is air leakage through the valve reduced?

Accepted Answer

By keeping the rotor-to-housing clearance tight, using adjustable wear tips as the valve ages, and adding gland packing or an air-purge shaft seal. A vent port can also be fitted to relieve the leakage path where the differential pressure is high.

Question 6

What process data are needed for a quotation?

Accepted Answer

Please provide the material and bulk density, required throughput, particle size, differential pressure and temperature, flange standard, and whether a quick-clean or hygienic build is required.

Question 7

How do I read the CY-RV model table?

Accepted Answer

Each row gives pocket volume, a typical speed and the motor. CY-RV-150 is 4 L/rev at 24 r/min, so the rotor displaces about 5.8 m³/h before fill efficiency. CY-RV-400 is 60 L/rev at 38 r/min. Multiply by bulk density only after a fill factor is agreed. Differential pressure and fine particles reduce the fill, so the table is a starting size, not a guaranteed tonnes-per-hour rating.

Question 8

When is a rotary valve the wrong feeder?

Accepted Answer

When the powder smears, sets, or wraps around a rotor. Sticky, pasty and fibrous solids are a poor fit for a standard airlock. Say so in the enquiry. A shaftless screw or a different discharge valve is often the better machine, and we would rather change the selection than force a rotary valve into that duty.

Question 9

What if my pressure differential is above 2 bar?

Accepted Answer

The usual listed duty is about 1.5 - 2 bar. The same CY-RV sizes can be quoted with blowing seals when the differential is higher. Send the actual pressure or vacuum on each side of the valve. Do not select from the standard row if the seal duty is outside that band.

Question 10

Do I need outboard bearings?

Accepted Answer

Use outboard bearings when the product is fine enough to reach an internal bearing, or when the temperature approaches the upper listed range of about 200 to 300 °C. Internal bearings keep the valve shorter. The choice is made from temperature and particle size, which should both be on the enquiry.

Model	Volume per rev (L)	Speed (r/min)	Motor (kW)
CY-RV-150	4	24	0.75
CY-RV-200	8	24	1.1
CY-RV-250	16	32	1.5
CY-RV-300	25	32	1.5
CY-RV-350	40	38	2.2
CY-RV-400	60	38	2.2

Series	Drop-through (round / square) · Standard · Blow-through · Quick-clean
Volume per rev	About 1.2 - 90 L/rev, series dependent
Typical models	RV-150 / 200 / 250 / 300 / 350 / 400, plus larger builds
Speed	Typically 3 - 42 r/min, 24 r/min common standard
Motor	About 0.55 - 4 kW, size dependent
Pressure duty	Typical differential about 1.5 - 2 bar, series dependent
Temperature	About -20 to 200 / 300 °C, bearing arrangement dependent
Flanges	DN100 - DN1200; PN10 / ANSI 150 / JIS / GB / custom
Capacity class	About 100 kg/h to 150 t/h, depending on series, speed and bulk density
Listed pocket volume	4 - 60 L/rev on CY-RV-150 to CY-RV-400. CY-RV drop-through models in the table use an 8-vane rotor.
How to start a size	Geometric displacement is pocket volume × speed. CY-RV-150 at 24 r/min displaces 4 L × 24 = 96 L/min before fill efficiency. Real throughput is lower once fill, bulk density and air leakage are applied.
Higher differential	Typical differential is about 1.5 - 2 bar. Blowing seals are available on the same size range when the duty needs a tighter seal.

Rotary Valve

About Rotary Valve

Working principle

Configuration and selection

Where it fits in the process

Key Features

Typical Specifications

Model range

General specifications

Suitable Materials

Chemical powders

Food powders

Battery materials

Minerals & cement

Plastics & granules

Pharmaceutical solids

Industries Served

Pharmaceutical

Where this equipment is running

Vacuum Conveying & Ton-Bag Packing for NCM / Anode Graphite

300 m Dense-Phase Transfer for LFP Powder with Ceramic Pipeline

Process Applications

Catalogs & Datasheets

Heavy-Duty Rotary Valve Datasheet

Blowing-Seal Hygienic Rotary Valve Datasheet

CYprocess Powder Handling Product Catalog (2026)

Rotary Valve FAQ

Enquire about Rotary Valve