Butterfly Valves
Butterfly Valves Worm Gear Actuator
Butterfly Valves Worm Gear Actuator is a group of 39 IMPA-coded items (codes 752211–752283) under Butterfly Valves in the Valves & Cocks section (IMPA 75). All of them are priced per piece. The list runs through imperial sizes from 1-1/2" to 32".
Buying guide
These are quarter-turn butterfly valves operated through a worm gearbox and handwheel instead of a lever. The group lists wafer-type bodies from 1-1/2 inch to 32 inch and semi-lugged bodies from 2 inch to 32 inch, each with its gear operator.
The gearbox makes larger valves easy to open and close against flow and holds the disc where it is set, so these are the isolating valves of sea-water cooling, ballast, bilge and fire lines. The engineer raises them when a seat liner wears and the valve passes, when the gearbox strips, or as dry-dock renewals.
How to specify it
Give size, body type (wafer or semi-lugged), the flange standard and class it fits between (JIS 5K/10K, DIN PN10/16 or ANSI 150), body, disc and seat materials, and the service fluid. Then give the face-to-face length of the valve being replaced: ISO 5752 standardises face-to-face dimensions for valves with flanged or wafer ends, including a series for short-pattern butterfly valves, so that a valve from another maker fits without modifying the pipework.[1]
If only the gearbox is being renewed, or a different actuator is to go on later, state the actuator mounting. ISO 5211 specifies the attachment of part-turn actuators, with or without gearboxes, to industrial valves; quote the mounting flange and stem details from the old valve so the new gearbox bolts on.[2]
Rules and certificates
Where the valve is a shell valve on an inlet or discharge, Load Line regulation 22(6) requires shell fittings and the valves required by that regulation to be of steel, bronze or other approved ductile material; valves of ordinary cast iron are not acceptable. State the body material on the requisition when the valve is for the ship’s side.[3]
Questions buyers ask
- Lever or worm gear — which do I need?
- Match what is fitted. The gear operator is used where a lever would be hard to move or to hold in position; lever-operated butterfly valves are listed in a separate group.
- Will a butterfly valve from another maker fit the same gap?
- Only if it is built to the same face-to-face series; ISO 5752 exists for that interchangeability, so give the series or the old valve’s length.
Sources
Published by Sherif Awad, founder of GeoMarineHub — in ship supply since 1990, a family business since 1981 (45 years). Last checked .
At a glance
Part of Valves & Cocks (IMPA section 75): Globe, gate, check, ball and butterfly valves, cocks and strainers, by standard, rating and material.
It is one of 6 groups under Butterfly Valves; the others include Butterfly Valves, Butterfly Valves Center Handle Actuator, Butterfly Valves Double Flanged Worm Gear Actuator, Butterfly Valves Double Flanged with Gear Box, Butterfly Valves Lock Lever Actuator.
Post the ones you need as a requirement and verified suppliers activated at your port bid on them — sealed, so nobody sees another bid.
- Items
- 39
- IMPA codes
- 752211–752283
- Priced
- per piece
- Sizes
- 1-1/2" – 32"
Items
Also under Butterfly Valves
Most requested sections