from The Century Dictionary.
- noun A valve for diminishing the pressure of a liquid or gas so that without preventing circulation the pressure in the pipe in which the valve is placed is greater on the side from which the flow comes; a reducing-valve.
Sorry, no etymologies found.
Here's a reduction-valve with an adiabatic expansion feature, to supply extra air to your heat-suit.
The use of the reduction-valve has made the automatic control of the oxygen supply much simpler than in the apparatus formerly used.
Having reduced the pressure to about 2 pounds by means of the reduction-valve, the supply of oxygen can be shut off by putting a pinch-cock on a rubber pipe leading from the reduction-valve to the calorimeters.
The cylinder is supported by a clamp K hung from the balance arm, and the reduction-valve A is shown at the top.
The details of the connections somewhat schematically outlined are given in fig. 32, in which D is the oxygen cylinder, K the supporting band, A the reduction-valve, and J the tension-equalizer attached to one of the calorimeters.
At this point, the supply of oxygen is cut off, the valve connecting the tension-equalizer with the main system is opened, and simultaneously the needle-valve on the reduction-valve of the oxygen cylinder is tightly closed, preliminary to weighing the cylinder.
With the type of cylinder at present in use, such leakage does not occur and therefore we simply attach to the oxygen cylinder a reduction-valve which reduces the pressure from 120 atmospheres to about 2 or 3 pounds to the square inch.