The Smith-Cooper International 9191L series swing check valve for potable water service 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. It has a forged brass disc and female National Pipe Taper (NPT) connections on both ends. Female NPT threads connect to male threaded pipes, creating a tighter seal than straight threads. This valve has maximum pressure ratings of 200 pounds per square inch (gauge) (psig) for water, oil, and gas (WOG), and the maximum working temperature is 350 degrees Fahrenheit. This valve meets National Sanitation Foundation (NSF)/American National Standards Institute (ANSI) 61-8 for quality assurance, and is certified to California AB1953
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.
Smith-Cooper manufactures a wide variety of pipe fittings and valves. The company is headquartered in Commerce, California, and meets relevant ANSI, ASTM, and International Organization for Standardization (ISO) 9002 standards.