39 needle valve diagram
Directional valves control the direction of flow and are identified by the number of ways or ports and their number of positions. The number of ways defines valve function with a way or port being either a line connection or an exhaust point. Positions identify the number of discrete operating positions of the valve element - typically most air For extra gripping power and a strong seal, these valves have Yor-Lok fittings with two sleeves that bite into tubing as you tighten the nut. All are compatible with Swagelok®, Let-Lok, and Parker A-Lok fittings. The 316 stainless steel body and seal, the PTFE seat and packing, and the Monel needle can withstand aggressive and corrosive solutions in chemical-processing applications. The two valves on the right beyond the pressure reducing valve control a cylinder. If the right coil is activated on the left most valve, the cylinder will retract slowly by gravity as metered by the needle valve. However, if the valve on the right is activ...