Limit Pressure Valve

pressure
The use of persuasion, influence, or intimidation to make someone do something
The continuous physical force exerted on or against an object by something in contact with it
The force exerted per unit area
coerce: to cause to do through pressure or necessity, by physical, moral or intellectual means :"She forced him to take a job in the city"; "He squeezed her for information"
a force that compels; "the public brought pressure to bear on the government"
the force applied to a unit area of surface; measured in pascals (SI unit) or in dynes (cgs unit); "the compressed gas exerts an increased pressure"

limit
Set or serve as a limit to
restrict: place limits on (extent or access); "restrict the use of this parking lot"; "limit the time you can spend with your friends"
the greatest possible degree of something; "what he did was beyond the bounds of acceptable behavior"; "to the limit of his ability"
restrict or confine, "I limit you to two visits to the pub a day"

valve
A device for controlling the passage of fluid through a pipe or duct, esp. an automatic device allowing movement in one direction only
control consisting of a mechanical device for controlling the flow of a fluid
A cylindrical mechanism in a brass instrument that, when depressed or turned, admits air into different sections of tubing and so extends the range of available notes
A membranous fold in a hollow organ or tubular structure, such as a blood vessel or the digestive tract, that maintains the flow of the contents in one direction by closing in response to any pressure from reverse flow
device in a brass wind instrument for varying the length of the air column to alter the pitch of a tone
a structure in a hollow organ (like the heart) with a flap to insure one-way flow of fluid through it