Gate valves are one of the most common valves used on ships. These valves generally are either fully open or fully closed.
When fully open, the fluid flows through the valve in a straight line with very little resistance. Gate valves should not be used in the regulation or throttling of flow because accurate control is not possible, and high-flow velocity in partially opened valves may cause erosion of the discs and seating surfaces.
An exception to the above is specially designed gate valves for...
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