3-Way Control Valve with Pneumatic Actuator can be used to combine two liquid flows or to reroute a liquid flow around or to the side of a device (bypass). The pressure drop across both flow pathways (inlet to outlet) needs to be almost identical to generate a steady flow for stable functioning. Stainless steel is used in the construction of the disc type design to provide a longer service life. Teflon seat rings are supplied up to 450°F for water or glycol type service, or for greater shut-off tightness.