A shuttle valve is designed to allow fluid flow from one of two sources, commonly used in pneumatic systems. It features a tube structure with three openings and functions by using a blocking element that directs fluid flow, preventing backflow between sources. Key applications include enhancing safety on machinery, controlling winch brake circuits, air pilot control, and managing standby or emergency systems.

1. Control Engineering
Topic :-Shuttle Valve
Guided By :- Prof. Dhaval Patel
Branch :- Mechanical Division :- 5C-2
Prepared By :- Saahil R. Kshatriya(150120119164)
GANDHINAGAR INSTITUTE
OF TECHNOLOGY(012)

2. Shuttle Valve
• A shuttle valve is a type of valve which
allows fluid to flow through it from one of two
sources. Generally a shuttle valve is used
in pneumatic systems, although sometimes it
will be found in hydraulic systems.

3. Structure and function
• The basic structure of a shuttle valve is like a tube with three
openings; one on each end, and one in the middle. A ball or other
blocking valve element moves freely within the tube.
• When pressure from a fluid is exerted through an opening on one
end it pushes the ball towards the opposite end.
• This prevents the fluid from traveling through that opening, but
allows it to flow through the middle opening.
• In this way two different sources can provide pressure without the
threat of back flow from one source to the other.
• In pneumatic logic a shuttle-valve works as an OR gate.

5. Applications
• The use of more switches on one machine: by using the
shuttle valve, more than one switch can be operated on a
single machine for safety, and each switch can be placed at
any suitable location. This application is normally used
with heavy industrial machinery.
• Winch brake circuit: a shuttle valve provides brake control
in pneumatic winch applications. When the compressor is
operated the shuttle valves direct air to open the brake
shoes. When the control valve is centered, the
brake cylinder is vented through the shuttle valve, and the
brake shoes are allowed to close.

7. Applications
• Air pilot control: converting from air to oil results in locking of the cylinder.
Shifting the four-way valve to either extreme position applies the air pilot
through the shuttle valve, holding the two air-operated valves open and
applying oil under air pressure to the corresponding side of the cylinder.
Positioning a manual valve to neutral exhausts the air pilot pressure, closing
the two-way valves, and trapping oil on both sides of the cylinder to lock it
in position.
• Standby and emergency systems: compressor systems requiring standby or
purge gases capability are pressure controlled by the shuttle valve. This is
used for instrumentation, pressure cables, or any system requiring
continuous pneumatic input. If the compressor fails, the standby tank—
regulated to slightly under the compressor supply—will shift the shuttle
valve and take over the function. When the compressor pressure is re-
established, the shuttle valve shifts back and seals off the standby system
until needed again.