Gearbox - M-Range | Alfa Gear

Name: Gearbox - M-Range | Alfa Gear
Brand: Alfa Gears
SKU: Gearbox - M-Range | Alfa Gear

ALFA Gear M Range Gearbox

The ALFA Gear M Range is a heavy-duty manual worm gearbox designed for quarter-turn (1/4 turn) operation of butterfly valves, ball valves, plug valves, and dampers. The range includes 11 sizes (M55 to M3200), covering output torques from 550 to 32,000 Nm.

Technical Specifications

Operating angle: 0–90°, with stop adjustment ±5°.
Gear ratios: 1:34 to 1:870, depending on size.
Weight: approx. 6 to 195 kg.
Valve interface: EN ISO 5211 or DIN 3210 (adaptable).
Max bore diameter: up to Ø160 mm (largest sizes).
Compatible with worm shaft extension and suitable for underground or submerged installations.

Construction and Sealing

Body, cover, flange, and position indicator are ductile cast iron JS1030. Worm is C45 carbon steel; shaft is SS304. Sealing by NBR 70 gaskets and O-rings. Fasteners are A2 stainless steel. Lubrication: Lithium EP2 grease.

Standard enclosure is IP67 (factory), with IP68 available on request. Confirm IP rating per order code.

Selection Criteria

Selection is not based solely on valve DN. Consider:

Maximum valve torque at differential pressure
Seat and sealing type
Idle time
Presence of solids or deposits in media
Required ISO 5211 flange
Stem interface: square, keyed bore, or custom machining

Installation

Valve and gearbox must be fully closed before assembly. Check flange alignment, stem/bore fit, and use A2/A4 fasteners. Apply gasket or liquid seal at interface to prevent moisture ingress.

Applications

For large valves in water, seawater, air, steam, cooling, HVAC, water treatment, industrial gases, and underground networks. Media compatibility is determined by the valve; gearbox is selected for torque, enclosure sealing, interface, and manual access.

FAQ

When to select M Range over E Range?
When higher torque, ductile cast iron construction, or up to 32,000 Nm is required.

What is checked during maintenance?
Open/close stops, enclosure sealing, handwheel, coupling, shaft alignment, fastener corrosion, and increased operating torque.

Datasheet and documents

Description

Heavy duty Ductile cast Iron (GGG40) quarter turn gearbox range. Standard IP68 Enclosure and available in 11 sizes up to 32000Nm.

Suitable for worm shaft extensions systems. Also applicable for underground, submerged applications.

11 sizes · up to 32.000Nm · IP68 Enclosure · Alfa Insert system

GENERAL TECHNICAL INFORMATION

Application

Alfa-Series quarter-turn worm gearboxes are applied to ball valves, butterfly valves, dampers and other 90° rotary valves. Alfa Gears hand wheels are with a variety models for optimal operation.

Operating Enviroment

Alfa Gears quarter-turn Worm gearboxes are with good mechanical quality and steady operating performance which apply to deal with variety climate and temperature. We strive to develop Alfa Gears valve gear operators to meet higher demands in the market.

Factory Standard

Enclosure: IP67 Standard (IP68 on request) Working Temperature: From -50°C to 150°C (-4°Fto248°F) Painting: Black RAL 9005, or according customer specification

Connect with Valve

The flange connecting to valve is according to EN ISO5211 or DIN3210 (Customization). including Sintered coupling system for various shaft connections. Please click on our link to download the Alfa Gears Dimensions or Alfa Gears Materials specification.