Valve Question?

Question

Has anyone heard of a "dead man closure ball valve (or auto closing ball valve)?" If so, could you tell me where to purchase one? I have looked all over.

Answer 1

McMaster-Carr catalog, page 390, shows a ball valve with a spring-return ( deadman ) handle. Sizes from 1/4" up to 2".

Answer 2

[Deadman System (DM):
Automatic shut off if the handle is dropped.
Abrasive flow is sealed at the nozzle end by a square sealing block.
Abrasive hose remains pressurized.
Full control of blasting at the handle.
Heavy duty design, few wear components, economical.]

Dead man is a control system which is operating the ball valve.

please visit:
http://www.freepatentsonline.com/4246924.html

on web page--click edit-find next-put "dead" in search.

Extract of the page:
Simultaneously, the valve arrangement is constructed in such a way that it permits a pressure regulation in the outgoing line in a particularly simple manner. If, for example, the adjusting force produced by the set of cup springs 18 via handwheel 28 is reduced so that, due to the pressure in the outgoing circuit, piston 11 is moved downwards somewhat and as a result tappet 10 forces ball 6 downwards and consequently the secondary flow path partly opens, so that accompanied by a pressure reduction in the outgoing circuit, part of the fluid supplied via port 2 flows back to the pump via the by-pass path. This possibility of simple pressure regulation has considerable practical significance because in this way it is possible to rapidly and easily, as well as without fluid loss and impairing operation to change from a high outgoing pressure such as is e.g. necessary for cleaning to a lower outgoing pressure such as is e.g. necessary after cleaning a stall or the like in order to spray a disinfectant. The operation of the unloader valve according to the invention is particularly significant in conjunction with the repeated and often long-lasting closure of the outgoing line, such as is for example the case in cleaning processes using a spray gun. As in such cleaning tasks and other applications, e.g.

when spraying pesticides, it is necessary to work at very high pressures, it is a requirement that the spray guns operate according to a so-called DEAD MANS CIRCUIT,

i.e. immediately and necessarily the closed position becomes effective in such spray guns if the operator releases the release means. To avoid a dangerous pressure rise on closing the spray gun in the known arrangement, precautions are taken by means of an electric switch provided on the spray gun, electric lines running between the spray gun and the pump driving motor and relay circuits on the pump motor to ensure that on closing the spray gun, the pump motor is switched off via the electrical signal path, thereby preventing a pressure rise.

for image:
http://www.kramerindustriesonline.com/images/ppb-series/kf45dm.jpg

Answer 3

Maybe it's similar to a "check" valve or anti-back flow valve
http://www.plumbingfittingsdirect.com/valves/30004.html

Answer 4

plumbing supply store