Browse Definitions :
Definition

valve

Contributor(s): Matthew Haughn

A valve is a mechanism that opens and closes to control the flow of fluids. In a scientific context, fluids include both liquids and gases – any substance that can flow freely – and valves may use either. Valves control fluid flow in motors, plumbing, irrigation, pneumatic and hydraulic systems. Sometimes the venerable pre-transistor vacuum tube is referred to as a valve as well.

The simplest valves are one way-flap mechanisms that allow flow in one direction and shut with back-flow pressure to stop flow in the direction of origin. (This is essentially how the valves in a heart work.) In addition to running automatically through the physics of flow itself, valves can also work through pressure or temperature and may be run by a motor or operated manually.

Manual valves are usually operated by levers, pedals, hand knobs or wheels to crank a screw-turned stem. A valve sometimes has geared mechanical insides that actuate the valve ball or disc against its seat, which may include a gasket. A valve may control fluid flow to one or, often, as many as four ports. Valves vary greatly in cost and size from as small as 0.1mm (millimeter) to as big as 5m (meters) in special applications.

Valve also happens to be the name of the game developer and purveyor of the largest game distribution service: Steam.

Watch a brief demonstration of how ball valves work:

This was last updated in January 2017

Continue Reading About valve

Join the conversation

1 comment

Send me notifications when other members comment.

Please create a username to comment.

Is an understanding of basic physics crucial to working in a DevOps environment?
Cancel

-ADS BY GOOGLE

File Extensions and File Formats

SearchCompliance

  • risk management

    Risk management is the process of identifying, assessing and controlling threats to an organization's capital and earnings.

  • compliance as a service (CaaS)

    Compliance as a Service (CaaS) is a cloud service service level agreement (SLA) that specified how a managed service provider (...

  • data protection impact assessment (DPIA)

    A data protection impact assessment (DPIA) is a process designed to help organizations determine how data processing systems, ...

SearchSecurity

  • computer worm

    A computer worm is a type of malicious software program whose primary function is to infect other computers while remaining ...

  • Single Sign-On (SSO)

    Single sign-on (SSO) is a session and user authentication service that permits a user to use one set of login credentials (e.g., ...

  • Certified Information Systems Auditor (CISA)

    Certified Information Systems Auditor (CISA) is a certification issued by ISACA to people in charge of ensuring that an ...

SearchHealthIT

SearchDisasterRecovery

  • business continuity plan (BCP)

    A business continuity plan (BCP) is a document that consists of the critical information an organization needs to continue ...

  • disaster recovery team

    A disaster recovery team is a group of individuals focused on planning, implementing, maintaining, auditing and testing an ...

  • cloud insurance

    Cloud insurance is any type of financial or data protection obtained by a cloud service provider. 

SearchStorage

Close