Model HCN Low-Noise Cage type Control Valves have been designed to remarkably reduce acoustic noise in services of compressible fluids such as steam, air, and natural gas. The cage has a large number of small holes and renders an ideal pressure reduction with a combination of two steps of “restriction” and “diffusion and expansion.” The fluid passage has been designed in an S-figure shape for smooth flow of fluid with less pressure loss and a stabilizer is provided as a strainer for flow near the cage, thereby permitting a large Cv value.
The valve plug is of a pressure-balanced type which allows control of high differential pressure with a small actuating force. The actuator is a compact but
high output diaphragm motor of a multiple spring type structured in a simple mechanism.
The model HCN valves, which are compact but of a low noise type and render high dynamic stability, are suitable especially for control of high temperature, high pressure, or high differential pressure process lines.