If the bore of the passage in a body is different (often smaller at the seat than at the flange connection) , this is called a reduced bore.
The diameter contraction can reduce the size of the parts, reduce the force required for opening and closing, and enlarge the application range of the parts. But after the bore reducing, the fluid resistance increases.
Under certain operating conditions in some sectors, such as pipelines in the oil sector, the use of reduced bore valves is not permitted. On the one hand, it is to reduce the resistance loss of pipeline, on the other hand, it is to avoid the obstruction of mechanical cleaning when getting through the passage.
Post time: Mar-06-2023