Engineers at Skinner Valve, a division of Parker Hannifin based in New Britain, Conn., have integrated several technological innovations to make its Skinner line of solenoid valves more consistent and reliable. They now laser weld the tube, tube stop, and flange on the sleeve assembly to eliminate the weak points, air gaps, and magnetic loss common in deep-drawn sleeves. Tube wall thickness is 25% thicker, which boosts pressure ratings, in some cases by up to 100%, and gives the direct-acting valves a life expectancy of 20 million cycles.
They redesigned the orifice and now hold 0.001-in. tolerances on the body-seat height. This results in more predictable flow rates and consistent power consumption levels during operation. They also redesigned the plunger, the valve's only moving part. The new design cuts manufacturing variations by 80% for greater valve-to-valve consistency. An automated plunger assembly ensures seals are properly inserted and held in place. Quality checks ensure uniform plunger length and spring forces. The manufacturing process increased the plunger's magnetic permeability and enhances the corrosion resistance, letting the valves perform with a wide variety of fluids and gases.