Inlet/Outlet Check Valves

Inlet/Outlet Check Valves are critical components in precision metering pumps that prevent backflow and ensure accurate, consistent fluid delivery. The inlet check valve opens during the suction stroke to allow fluid into the pump chamber, then closes during the discharge stroke. The outlet check valve opens during the discharge stroke to allow fluid out of the pump chamber, then closes during the suction stroke. This coordinated operation maintains precise volumetric control and prevents contamination or mixing of fluids. These valves operate on a pressure differential principle. When pressure on the inlet side exceeds the pump chamber pressure, the inlet check valve opens to allow fluid entry. During discharge, when pump chamber pressure exceeds outlet pressure, the outlet check valve opens. Both valves close automatically when pressure differential reverses, using spring force, ball/poppet weight, or flexible diaphragm action to create a positive seal against backflow. Materials on file include stainless steel, PTFE, ceramic, and elastomers. The primary specification is valve seat diameter and connection size, measured in millimeters. These valves are used in applications requiring precise dosing, such as chemical processing, pharmaceutical manufacturing, and water treatment. They are selected based on fluid compatibility, pressure and temperature requirements, and flow rate. Verification of model-specific dimensions, materials, and performance should be confirmed with the legal manufacturer or supplier. Regular inspection for wear, leakage, or sticking is recommended to maintain accuracy. Failure to operate correctly can lead to inaccurate dosing, backflow, or system contamination.

These valves operate on a pressure differential principle. When pressure on the inlet side exceeds the pump chamber pressure, the inlet check valve opens to allow fluid entry. During discharge, when pump chamber pressure exceeds outlet pressure, the outlet check valve opens. Both valves close automatically when pressure differential reverses, using spring force, ball/poppet weight, or flexible diaphragm action to create a positive seal against backflow.