Regulating Valve

a device used to regulate temperature, pressure, flow rate, and other parameters. Regulating valves are used in automatic control and regulating systems and influence the course of technological and heat-and-power engineering processes in accordance with the supplied instructions.

Regulating valves are installed on trunk and industrial pipelines and engineering equipment, installations, and reservoirs. A regulating valve consists of a regulating unit (the valve itself), which varies the flow cross section, and an actuating mechanism, which is a pneumatic drive that receives instructions from an automatic regulator of a remote-controlled device and transmits these instructions to the regulating unit.

Regulating valves are classified on the basis of their nominal capacity as medium-flow, small-flow, and microflow valves and on the basis of nominal pressure as low-pressure, medium-pressure, and high-pressure valves. They operate at temperatures between -225° and 450°C. There are many different types of regulating valves, including single- and double-seat, pass, angled, and three-way valves. Double-seat valves with spring-loaded diaphragms as actuating mechanisms are most commonly found.

The regulating unit has a flanged throughput section and consists of top and bottom covers, a plunger, and a housing into which two seats have been screwed. A coupling nut connects the plunger rod to the rod of the actuating mechanism, which is fastened to the top cover of the regulating unit. The diaphragm senses a standard command signal (0.02–0.1 meganewtons/cm² of air pressure) and transmits its force to the return spring of the mechanism, which leads to the displacement of the rod with the gate and a change in the flow cross section, resulting in a change in the valve’s throughput capacity.