The Control Devices ball-type check valve provides tight sealing, and can be used as a tank check valve for small compressors or as a component in pneumatic circuits. The valve body is made of brass for corrosion resistance, ductility at high temperatures, and low magnetic permeability. Brass can be connected to copper, brass, plastic, aluminum, and welded steel. Fluorocarbon O-rings provide higher temperature and chemical resistance. It has female National Pipe Taper (NPT) threads on one end and male NPT threads on the other for connecting a male and a female threaded pipe. The NPT threads create a tighter seal than straight threads. The maximum pressure rating is 250 pounds per square inch (psi), and the maximum temperature is 250 degrees Fahrenheit. Check valves have two ports and restrict the flow of fluids and other loose materials through a pipe or passageway to one direction. Flow enters through one port and exits through the other, closing when flow reverses or stops. Two common types of check valves are ball cone valves and swing check valves. A ball cone valve utilizes a spring-loaded ball seated against a cone-shaped interior surface to stop the flow of fluid in a forward direction, and a swing check valve has a movable disc on a hinge to block reverse flow. Check valves are rated by their cracking pressure (the minimum upstream pressure required for the valve to operate), and they are used in various water, gas, air, and steam lines. Control Devices manufactures specialty valves, nozzles, and condensate traps. The company, founded in 1963 and headquartered in Fenton, MI, meets ASME standards.
