Precision Dispensing Needle Valves Information
Precision dispensing needle valves are designed to provide precise fluid dispensing depending on applications. The dispensed output can be in the form of a bead, dot or fill. The valve dispenses fluid when the activator (for example, air) acts on a piston, which shifts the spool or needle into the open position. A second actuator (for example, fluid pressure) forces the fluid to flow. When the valve activator is stopped, a spring force shifts the spool or needle to the closed position.
Dispensing needle valves have a slender, tapered point at the end of the valve stem that is lowered through the seat to restrict or block flow. Fluid flowing through the valve turns 90 degrees and passes through an orifice that is the seat for a rod with a cone shaped tip. Precision dispensing needle valves are widely used to accurately regulate the flow of liquids and gases at low flow rates. The fine threading of the stem and the large seat area allow for precise resistance to flow.
Dispensing needle valves are used to control flow into delicate gauges, which might be damaged by sudden surges of fluid under pressure. Needle valves are also used in situations where the flow must be gradually brought to a halt and at other points where precise adjustments of flow are necessary or where a small flow rate is desired. They can be used as both on/off valves and for throttling service.
Precision dispensing needle valves can be used for a range of applications, including adhesive/silicone, chemical, cleaners, paints and coatings, food and beverage, high viscosities, and lubricants. Many additional applications for precision dispensing needle valves are also available. Important specifications to consider when choosing precision dispensing needle valves are dispense rate, dispensed width or diameter, shot size, operating frequency, and metering accuracy.