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A <a href="http://www.vickers-fluidpower.com/piston-pump/"
target="_self">piston pump</a> is a type of positive displacement
pump where the high-pressure seal reciprocates with the piston.
Piston pumps can be used to move liquids or compress gases. They can
operate over a wide range of pressures. High pressure operation can
be achieved without a strong effect on flow rate. Piston pumps can
also deal with viscous media and media containing solid particles.
This pump type functions through a piston cup, oscillation mechanism
where down-strokes cause pressure differentials, filling of pump
chambers, where up-stroke forces the pump fluid out for use. Piston
pumps are often used in scenarios requiring high, consistent
pressure and in water irrigation or delivery systems.<br/>
</p>
<p>
A <a href="http://www.vickers-fluidpower.com/vane-pump/"
target="_self">vane pump</a> is a self-priming positive displacement
pump providing constant flow at varying pressures. Operation is via
a motor connected to a gearbox as typically the maximum rpm is 900.
The pump is fitted with a relief valve to prevent the pump from
building to a pressure which may damage the pump.
</p>
<p>
A<a href="http://www.vickers-fluidpower.com/gear-pump/"
target="_self"> gear pump</a> is a type of positive displacement
(PD) pump. It moves a fluid by repeatedly enclosing a fixed volume
using interlocking cogs or gears, transferring it mechanically using
a cyclic pumping action. It delivers a smooth pulse-free flow
proportional to the rotational speed of its gears.
</p>
<p>
An <a href="http://www.vickers-fluidpower.com/gear-
pump/external-gear-pump/" target="_self">external gear pump</a>
utilizes two identical gears meshed side by side, where one gear
(driving) is driven by a motor, and it – in turn – drives the
other gear (driven) driving gear driving the idle (driven) gear.
Each gear is supported by a shaft with bearings on both sides of the
gear.
</p>
<p>
An <a href="http://www.vickers-fluidpower.com/gear-
pump/internal-gear-pump/" target="_self">internal gear pump</a>
moves a fluid by repeatedly enclosing a fixed volume within
interlocking gears, transferring it mechanically to deliver a smooth
pulse-free flow proportional to the rotational speed of its
gears.<br/>
</p>
<p>
<a href="http://www.vickers-fluidpower.com/directional-control-
valve/" target="_self">Directional control valves </a>(DCVs) are one
of the most fundamental parts of hydraulic and pneumatic systems.
DCVs allow fluid flow (hydraulic oil, water or air) into different
paths from one or more sources. DCVs will usually consist of a spool
inside a cylinder which is mechanically or electrically actuated.
The position of the spool restricts or permits flow, thus it
controls the fluid flow.
</p>
<p>
A <a href="http://www.vickers-fluidpower.com/directional-
control-valve/solenoid-valve/" target="_self">solenoid valve</a> is
an electrically controlled valve. The valve features a solenoid,
which is an electric coil with a movable ferromagnetic core
(plunger) in its center. In the rest position, the plunger closes
off a small orifice. An electric current through the coil creates a
magnetic field. The magnetic field exerts an upwards force on the
plunger opening the orifice. This is the basic principle that is
used to open and close solenoid valves.
</p>
<p>
<a href="http://www.vickers-fluidpower.com/directional-control-
valve/manually-actuated/" target="_self">Manually Actuated</a>
employs levers, gears, or wheels to facilitate movement while an
automatic actuator has an external power source to provide the force
and motion to operate a valve remotely or automatically.
</p>
<p>
A <a href="http://www.vickers-fluidpower.com/on-off-
valve/check-valve/" target="_self">check valve</a>, non-return
valve, reflux valve, retention valve, foot valve, or one-way valve
is a valve that normally allows fluid (liquid or gas) to flow
through it in only one direction.
</p>
<p>
<a href="http://www.vickers-fluidpower.com/proportional-
valve/pressure-control/" target="_self">Pressure control</a> (PC) is
a mode of mechanical ventilation alone and a variable within other
modes of mechanical ventilation. Pressure control is used to
regulate pressures applied during mechanical ventilation. Air
delivered into the patients lungs (breaths) are currently regulated
by Volume Control or Pressure Control. In pressure controlled
breaths a tidal volume achieved is based on how much volume can be
delivered before the pressure control limit is reached.
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