Blast valve

Blast valve

A blast valve is used to protect a shelter, such as a fallout shelter or bunker, from the effects of sudden outside air pressure changes. A nuclear weapon creates a shock wave, which may produce sudden pressure changes of more than an atmosphere (about 15 pounds per square inch) even several miles or kilometers from the detonation point. After the shock wave passes, a sudden negative pressure follows.

If such pressure waves enter a shelter, they will likely do substantial harm to occupants and equipment. A blast valve is placed in air intake/exhaust pipes, that remains open normally, but automatically closes when strong pressure is applied in either direction.

A typical blast valve has entries of 6-12" diameter (150-300 mm), and a larger center section. Within the center section is a disk mounted on an axle, with weak springs that keep it centered, away from both entries. Pressure displaces the disk along the axle, until it plugs one entry or the other. After the blast, the springs return the disk to the center, re-opening the valve.

[ Blast valve pictures and manuals]

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • cold-blast valve — Смотри клапан холодного дутья …   Энциклопедический словарь по металлургии

  • hot-blast valve — Смотри клапан горячего дутья …   Энциклопедический словарь по металлургии

  • Blast shelter — A blast shelter is a place where people can go to protect themselves from bomb blasts. It differs from a fallout shelter, in that its main purpose is to protect from shock waves and overpressure, instead of from radioactive precipitation, as a… …   Wikipedia

  • Valve — This article is about the flow control device. For the game developer, see Valve Corporation. For the electronic component, see Vacuum tube. For other uses, see Valve (disambiguation). These water valves are operated by handles. A valve is a… …   Wikipedia

  • blast gate — noun : a damper (as of the butterfly valve type) used for controlling the volume of a blast of air or exhaust gases …   Useful english dictionary

  • Blast regulation valve — Клапан, регулирующий подачу воздуха …   Краткий толковый словарь по полиграфии

  • Safety valve — A safety valve is a valve mechanism for the automatic release of a gas from a boiler, pressure vessel, or other system when the pressure or temperature exceeds preset limits. It is part of a bigger set named pressure safety valves (PSV) or… …   Wikipedia

  • Gresley conjugated valve gear — The Gresley conjugated valve gear was a valve gear for steam locomotives designed by Sir Nigel Gresley, chief mechanical engineer of the LNER, assisted by Harold Holcroft. It enables a three cylinder locomotive to operate with only the two sets… …   Wikipedia

  • Air valve — Air Air ([^a]r), n. [OE. air, eir, F. air, L. a[ e]r, fr. Gr. ah r, air, mist, for a[digamma]hr, fr. root a[digamma] to blow, breathe, probably akin to E. wind. In sense 10 the French has taking a meaning fr. It. aria atmosphere, air, fr. the… …   The Collaborative International Dictionary of English

  • Exhaust valve — Exhaust Ex*haust , a. [L. exhaustus, p. p.] 1. Drained; exhausted; having expended or lost its energy. [1913 Webster] 2. Pertaining to steam, air, gas, etc., that is released from the cylinder of an engine after having preformed its work. [1913… …   The Collaborative International Dictionary of English

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”