Teledyne hfc-303-307 ユーザーズマニュアル

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Manual: 152-082010 301-305-306_303-307 Series
 
Page 23 of 35 
3.7. Control  Valve 
The control valve is an “automatic metering solenoid” valve (see Figure 3-3). While most solenoid valves 
operate in either the fully open or closed positions, the automatic metering solenoid valve is designed to 
control flow. A spring is used to hold a magnetic plunger assembly tightly against an orifice, thereby 
shutting off the flow. The magnetic plunger assembly is surrounded by a coil of magnet wire. When the 
coil is energized the electric current passing through the wire coil produces a magnetic field which 
attracts the plunger. The plunger assembly moves away from the orifice allowing the gas flow to pass 
between the orifice and the plunger seat. The distance between the orifice and the plunger seat, and 
thus the flow through the valve, is controlled by the amount of current supplied to the coil. 
The valve seat is made of Kalrez (or equivalent) perflouroelastomer. The valve orifice is made from 316 
stainless steel. The valve plunger and pole piece are made of nickel plated magnetic alloy (Hi-perm 49) 
and the control springs are made of 302 stainless steel. The Diaphragm and all seals are as specified per 
the customer order (Viton, Neoprene, Buna-N or Kalrez). 
 
 
Figure 3-3