Steam Main Jargon Buster


Where pressure is lower than atmospheric pressure.

Vacuum breaker

A type of valve which is design to protect plant and equipment from damage when vacuum conditions are experienced. When a system cools some parts of the system may experience vacuum conditions, a vacuum breaker should automatically open and let air in so that the vacuum condition does not cause damage.

Valsteam Adca Engineering SA

A company which manufactures a range of steam products (steam traps and valves etc.). The company is based in Portugal.


A type of pipe fitting. Valves can be used to stop the flow of a medium or to control it. They come in many different types and sizes depending on the application.

Vent head

A device typically fitted to the top of a vent pipe. Its role is to dissipate the velocity of vapour ejected to atmosphere. It would typically be used on the vents from vented condensate recovery units.


The resistance of a fluid to flow when subjected to a sheer stress.


Viton is fluorocarbon rubber used for 'O' rings, inserts, diaphragms, sleeves, etc. It is a registered trade mark of DuPont Performance Elastomers L.L.C. It is generally specified for higher temperature applications. Advantages are resistance to erosion and corrosion, and the ability to give a leak tight seal. Reference should always be made to manufacturer's recommendations prior to specifying and use.

Volumetric flowrate

The rate of flow expressed as a volume.

© Copyright Steam Main Limited 2017-2018 All Rights Reserved

Site by Banilla