Electric expansion valves for precise liquid injec
tion in evaporators for air conditioning and refrigeration applications.The valve piston and linear positioning design is fully balanced, providing bi-flow feature as well as solenoid tight shut-off function in both flow directions.The valves design uses bipolar drive providing very precise flow regulation.
Siemens, Alco, Emerson, Danfoss, Carel Perfect refrigerant tightness: despite the rotary motion of the motor, the movable element does not rotate during movement.
This allows the use of a high quality Teflon seal, which rests gently on the valve seat, without any sliding.
To improve tightness of the seal, an elastic steel spring is fitted that pushes the movable element against the seat when the system is closed: this moreover allows the motor to complete a number of extra turns before stopping.
The energy accumulated by the spring in this stage gives additional energy to close the valve, meaning tightness values that are comparable to those provided by a traditional solenoid valve.