clack valve

English

Noun

clack valve (plural clack valves)

1. (engineering) A valve; especially one hinged at one edge, which, when raised from its seat, falls with a clacking sound.
   • 1946 March and April, “The Why and The Wherefore: Clack-Boxes”, in Railway Magazine, page 129:

     The connecting pipe between a locomotive injector and the boiler, through which the water is forced into the boiler against the steam pressure within, is provided with a "clack-valve," which allows the water to pass in the inward direction only and not the outward; this is housed in a "clack-box". No question of "advantages or disadvantages" attaches to the use of a clack-box; it is a necessary part of locomotive equipment.

   • 1959 September, P. Ransome-Wallis, “The British Railways Class "9" 2-10-0s”, in Trains Illustrated, page 420:

     The feed water enters the back and cool end of the preheater and passes forward to the front and hot end, after which it enters the boiler through a clack valve.

Related terms

• clack box

Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.
(See the entry for “clack valve”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.)