Bellows Valves
Introduction:
Bellows valve is a pressure balanced regulating valve with compact valve body, S-streamline fluid channel, small pressure drop loss, large flow and wide adjustable range.
Valves with bellows as stem sealing element. It is often used in the occasion with strict requirements on valve stem sealing, such as the occasion of high vacuum and nuclear industry.
The bellows is used to replace the stuffing box on the ordinary valve or be used together with the stuffing box, so that there is no leakage at the valve stem, so as to prevent the leakage of radioactive substances or valuable substances, or to maintain a high vacuum.
Product features:
The bellows will expand and contract with the rising and falling of the valve rod, and its maximum working pressure depends on the compressive strength and fatigue strength of the bellows.
Its working principle is that when the handle rotates, it drives the valve head assembly associated with the valve stem to open the valve.
The medium is separated from the atmosphere by bellows,
It is a valve without packing.
The sealing performance is reliable, but the structure is complex and the cost is high. Compared with the diaphragm valve, the dead zone volume is large.
Structure:
The upper valve cover adopts corrugated pipe seal structure, which can completely eliminate the possibility of process medium leaking out from the valve stem movement clearance, which is one of the remarkable features of corrugated pipe seal valve. Due to the deformability and outstanding aging resistance of the bellows element, this type of regulating valve completely overcomes the weaknesses of packing aging and temperature difference sensitivity that usually exist in packing seal valves. Secondly, the double sealing structure of corrugated pipe and packing is adopted, which has better safety and reliability. Therefore, it is widely used in the automatic control system of rare special media such as highly toxic, highly corrosive, radioactive, etc. The regulating valve is equipped with a multi spring membrane actuator, which has a compact structure and large output force. Leakage: metal valve seat: in accordance with ANSI Bl6.104 Grade VI, less than 0.5% of rated Cv; PTFE valve seat: the standard conforms to ANSIBl6.104VI, and the return difference is less than 10-7 of rated Cv: 5% (without positioner); 3% (with positioner) Linearity: ± 11% (without positioner); ± 3% (with locator) Remarks: standard V-shaped PTFE packing is used.
Product Showing:
