ENGINEERED FOR THE PROCESS

Rotary Valve Selection Guide: 7 Sizing Steps

Use this engineering checklist to turn process conditions into a comparable rotary valve specification.

Use process data—not inlet size alone

Start with the material, required throughput, pressure differential, temperature and installation interface. These inputs determine whether a proposed rotary airlock can meter consistently, limit leakage and remain serviceable in the actual process.

Use this guide to

Compare quotations against the same operating conditions.
Identify when pressure, abrasion, stickiness, cleaning or temperature needs special review.
Prepare the information needed for a capacity check and project drawing.

Confirm before ordering

Supplier-specific capacity and leakage data for the proposed configuration.
An approved dimensional drawing covering flanges, height, drive orientation and maintenance space.
Materials, motor supply, controls and any hazardous-area requirements with the responsible project engineer.

Nominal inlet size alone does not determine capacity or replacement compatibility. Use the seven-step workflow below, then verify the final selection against the approved project data.

SELECTION WORKFLOW

Seven inputs that determine rotary valve selection

A model name or flange size is not enough for reliable selection. Record the process data below before comparing quotations or approving a drawing.

StepConfirmWhy it matters

01Material and particle behaviorFlowability, abrasiveness, stickiness and particle size affect pocket shape, surfaces and clearance.

02Required mass or volume flowCapacity determines usable rotor displacement and speed. Use the capacity formula for a first estimate.

03Pressure differential and leakage limitAirlock duty needs suitable clearances, end sealing and venting for the actual pressure condition.

04Normal and maximum temperatureThermal expansion changes operating clearance and can influence materials, bearings and seals.

05Contact material and surface finishCarbon steel, stainless steel, coatings or wear protection should match product and cleaning needs.

06Flange, height and drive orientationVerify the complete installation envelope with the dimension checklist, not only the inlet opening.

07Duty cycle, motor supply and maintenanceContinuous duty, starts per hour, controls and access affect the drive and service arrangement.

For pressure conveying

Prioritize leakage control, venting, rotor clearance and shaft-end sealing.

For abrasive powder

Review rotor tip speed, replaceable wear areas, surface treatment and inspection access.

For sticky material

Review pocket geometry, surface finish, speed and whether upstream flow assistance is required.

PREPARE A COMPARABLE QUOTATION

Turn the seven steps into an enquiry

Copy this checklist into Requirement / notes, complete the fields you know and mark the others as unconfirmed. Provide normal and maximum conditions separately where relevant.

Material and particle size:
Loose bulk density (kg/m³):
Required capacity (kg/h or m³/h):
Inlet and outlet pressure, with units:
Normal / maximum temperature (°C):
Contact material and cleaning requirements:
Inlet / outlet opening and flange bolt pattern:
Face-to-face height and drive / maintenance space:
Motor voltage, frequency and duty cycle:
Fixed replacement dimensions or drawing reference:
Unknown items requiring confirmation:

Use the capacity calculator for the throughput estimate and the drawing checklist for installation measurements. If a unit is used for pressure isolation, state the inlet and outlet pressure conditions as well as the material flow requirement.

Send the completed selection checklist

Request confirmation of the proposed configuration, capacity assumptions and installation drawing before approving manufacture.

APPLICATION NOTES

Engineering considerations for Rotary Valve Selection Guide

The main design objective is turning process data into a valve configuration that can be manufactured and maintained. Confirm material behavior, capacity, pressure, temperature, connection and controls before fixing the valve size, rotor and drive arrangement.

A complete data sheet reduces assumptions and makes quotations technically comparable. Sercan reviews these details against capacity, installation interface and maintenance access before issuing a project drawing.

When installation interfaces are fixed

For an existing valve replacement or restricted installation space, review the customized rotary valve requirements. Supply the measured interfaces and identify which dimensions cannot change; a model name alone does not confirm compatibility.

Recommended project checks

Provide representative material and bulk density data.
State normal and maximum temperature and pressure conditions.
Confirm flange dimensions, available height and drive orientation.
Define the expected duty cycle and maintenance target.

TECHNICAL FAQ

Questions before selection

What information is needed to select a rotary valve?

Provide the material, particle size, loose bulk density, required capacity, temperature, pressure differential, flange dimensions, motor supply and duty cycle.

Can flange size alone determine rotary valve capacity?

No. Capacity depends on usable rotor displacement, speed, filling efficiency and bulk density. Two valves with the same inlet size can have different throughput.

When is a blow-through rotary valve considered?

It may be considered when material must discharge directly into a pneumatic conveying line, subject to product behavior, conveying air and pressure conditions.