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HB Series Control Valve with Pneumatic Actuator
The HB Series is a high performance, general service control valve designed using Computational Fluid Dynamics (CFD) for high control accuracy, optimized flow characteristics and extended service life. These control valves, with stainless steel bodies, are equipped with a contoured plug design to withstand the rigorous nature of steam service and are compatible with many fluids and environments. Modern manufacturing techniques and modular construction allows these stainless steel valves to be extremely cost-effective in comparison to valves with bronze, cast iron or cast steel bodies. The standard configuration has an equal percentage flow characteristic with metal-to-metal seating, spring-loaded Teflon V-ring stem packing and pneumatic actuator. The HB Series is available with both pneumatic or electric actuation.
HB Series-Pneumatic How It Works
A control valve is a device capable of modulating flow at varying degrees between minimal flow and full capacity in response to a signal from an external control device. The valve modulates flow through movement of a valve plug in relation to the port(s). The pneumatic actuator directs the movement of the stem as dictated by the external control device.
When selecting a 2-Way Control Valve, the failure mode should be considered if the signal controlling the actuator becomes interrupted. For heating applications using steam, a Normally-Closed/Air-To Open (ATO) Valve should be selected. If the air signal to the actuator is interrupted, the valve will close to prevent overheating. For cooling applications with water, a Normally-Open/Air-To Close (ATC) valve should be selected. In addition to selecting the fail-safe mode, ensure the maximum Close-off Pressure of the valve exceeds the inlet pressure. This is necessary to guarantee the valve assembly will overcome the forces generated in the valve body from the fluid pressure, allowing the valve to open and close properly and completely. A Type 2000 Positioner can be used to increase close-off pressure of the valve.
Valve Positioner
Type 2000 Valve Positioners (Pneumatic or Electro-Pneumatic) improve control accuracy and increase maximum close-off pressure capability of the valve. The Positioner is mounted to the valve’s yoke assembly and linked to the valve stem. It receives a signal from the electronic controller and compares the control signal to the actual position of the valve plug. The Positioner then sends a corrected signal to the valve’s actuator, thereby positioning the valve plug for optimum flow modulation.
The Pneumatic Positioner receives a 3-15 PSIG air signal normally taken from an I/P Transducer.
The Electro-Pneumatic Positioner receives an electrical 4-20 mA or 0-10V signal directly from the PID Controller and therefore eliminates the need for a separate I/P Transducer.
HB Series-Pneumatic Model Coding
The Actuator can be specified to operate the valve for either Air-to-Open (Normally Closed) or Air-to-Close (Normally Open), but can also be re-configured in the field if needed.
Ensure the maximum Close-Off Pressure of the valve exceeds the Inlet Pressure. This is necessary to guarantee the valve assembly will overcome the forces generated in the valve body from the fluid pressure, allowing the valve to open and close properly and completely.
** To Complete Full Model Code, Must Specify: Trim, Packing, Actuator and Control Signal Type
The HB Series are stainless steel valves (up to 4") and built to withstand the rigorous nature of steam service as well as air and water service. The Pneumatically operated HB Series is also available with the Type 2000 Valve Positioner