Full Open Operation
When operating pressure below the
diaphragm is greater than the
pressure in the cover chamber, the
valve is held open, allowing full
flow.
Tight Closing Operation
When pressure below the
diaphragm is relieved and operating
pressure is applied to the cover
chamber, the valve closes
drip-tight.
• Reduced Cavitation Design
• Drip-tight, Positive Seating
• Service Without Removal From Line
• Globe or Angle Pattern
• Every Valve Factory-Tested
600 Series
Powertrol Valve
The Cla-Val Model 100-21 is a hydraulically operated,
diaphragm actuated, globe or angle pattern valve. It consists
of four major components: the body, intermediate chamber,
diaphragm assembly and cover. The diaphragm assembly is
the only moving part.
The diaphragm assembly, which is guided top and center by
a precision machined stem, utilizes a non-wicking diaphragm
of nylon fabric bonded with synthetic rubber. The diaphragm
forms a seal between the cover chamber and intermediate
chamber. A synthetic rubber disc retained on three and one-
half sides forms a drip-tight seal with the renewable seat
when pressure is applied above the diaphragm. As pressure
above the diaphragm is relieved and pressure is applied
below the diaphragm, the valve opens wide for full flow. The
rate of closing or opening can be controlled by modulating
the pressure above or below the diaphragm.
The Model 100-21 is recommended where independent
operating pressure is desired. The valve's packless
construction and simplicity of design assures a long life and
dependable operation. Available in various materials and in
a wide range of sizes. It's applications are many and varied.
100-21
Principle of Operation
The valve holds any intermediate
position when operating pressure is
equal above and below the
diaphragm. A Cla-Val four-way pilot
control with "lock" position can
maintain this balance by stopping
flow in the pilot control system.
Modulating Action
4 - Way Control
4 - Way Control
4 - Way Control with lock
MODEL
see page 2 for
approvals
