| 摘要 |
PURPOSE:To prevent a guide portion from being adhered by a fluid by providing a valve plug having a guide portion, the section of which is polygonal, and letting a flash liquid flow between a guide ring and a valve plug. CONSTITUTION:A valve stem 1 is driven by air pressure, so that valve plugs 2, 3 are moved up and down to open and close a valve. Generally, the section of the valve plug 3 contacting a guide ring 4 is preferably polygonal such as tetragonal, pentagonal, hexagonal, heptangular or octanogal, and the ridgeline of each vertical angle is slided in contact with the inner surface of the guide ring 4. A flash liquid introduced through a flash liquid nozzle 5 flows through a gap arc-shaped in section between the guide ring and the valve plug 3. Adhesion between the guide ring 4 and the valve plug 3 caused by slurry or polymerized fluid can be prevented by letting a flash liquid flow therebetween. |
