A Globe Valve is a linear-motion shutoff valve with an internal baffle that throttles fluid flow by moving a plug toward or away from a conical seat. Globe valves excel at precise flow control in HVAC systems where modulation and pressure drop are required.
Design and Characteristics
Globe valves feature a spherical body with a perpendicular inlet and outlet connection, causing a 90-degree flow path change internally. This design creates significant pressure drop (typically 3-8 psi at rated flow), making them ideal for high-pressure applications. The valve’s throttling capability allows proportional flow control from 0 to 100 percent of rated capacity. Sizes range from 1/2-inch to 2-inch nominal diameter in HVAC applications, with flow coefficients (Cv) between 2 and 25.
HVAC Applications
Globe valves serve effectively as control valves for chilled water and hot water systems where modulating control is necessary. Their high pressure-drop capability suits applications with variable-speed pumps and balancing requirements. However, globe valves require higher actuator forces than ball or butterfly designs, increasing operating costs. They are less suitable for applications requiring low pressure drop or full shutoff.