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|  MIL-V-17501F(SH)
3.3 Recovered materials Unless otherwise specified herein, all equipment, material, and
articles incorporated in the products covered by this specification shall be new and may be
fabricated using materials produced from recovered materials to the maximum extent practicable
without jeopardizing the intended use. The term "recovered materials" means materials which have
been collected or recovered from solid waste and reprocessed to become a source of raw materials,
as opposed to virgin raw materials. None of the above shall be interpreted to mean that the use
of used or rebuilt products is allowed under this specification unless otherwise specifically specified.
3.4 Component parts. Table I lists the general component parts and their application to the
valves covered in this specification. The part's application is intended for guidance only; however,
when parts listed are incorporated in the valve construction, materials of such parts shall be as
specified. This general guidance shall not relieve the contractor from delivering valves that meet
the specified requirements of this document.
3 . 5 Construction. Control valves shall be constructed for usc with seawater. Functional
construction characteristics for type I, class 1 through 6, and type II valves shall be as specified in
3.5. 1 through 3.5.3 (see 6.3). Weight and size of the assembled valves shall be kept to a minimum.
3.5.1 Design pressure. Control valves shall be constructed for an internal operating pressure
of 250
and shall withstand an internal test pressure as specified in 4.6.3. The bonnet, dome,
cover, or distributor portion of the valve shall be constructed to withstand the highest control
pressure to which it will be subjected in the specified working range.
3.5.2 Type I. Control valves of the type I classification shall be constructed for hydraulic
operation. The movement of the valve disc shall be positively actuated by hydraulic pressure upon
the diaphragm when subjected to a minimum fluid pressure of 40
while controlling fluids in
a range of 40 to 250
Diaphragms shall not be employed as a disc or seating element. Control
valves shall be constructed so that failure of the diaphragm will cause the valve to remain closed
and shall seat with line pressure. Control valves shall be of the globe pattern construction in which
all moving parts shall be guided. Type I valve construction shall be as specified (see 3.6 through
3.6.16).
3.5.2.1 Class 1. Sprinkler supply valves shall be constructed to be held in the closed position
by a combined force of valve spring and inlet firemain supply pressure acting on the valve disc. The
valves shall be constructed to open rapidly when actuated by hydraulic pressure and close rapidly
when hydraulic pressure is released. These valves shall permit control of seawater flow to the
system's sprinkler head valves. Class d valves shall be constructed with an atmospheric vent, a valve
position indicator, a test fitting, and a manual actuation mechanism.
3.5.2.2 Class 2. The remote control valve shall be constructed to be held in the closed
position by an internal valve spring when the control system piping is not pressurized. The valve
shall be constructed to open fully and close completely when actuated by hydraulic pressure. This
valve shall permit securing of the sprinkler supply valve from an operation station other than the
one from which actuation occurred.
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