德國托克（TOK）進口膜盒式蒸汽疏水閥的主要動作元件是金屬膜盒，內充一種氣化溫度比水的飽和溫度低的液體。裝置剛啟動時，管道出現低溫冷凝水，膜盒內的液體處于冷凝狀態，閥門處于開啟位置。當冷凝水溫度漸漸升高，膜盒內充液開始蒸發，膜盒內壓力上升，膜片帶動閥芯向關閉方向移動，在冷凝水達到飽和溫度之前，疏水閥*關閉。膜盒隨蒸汽溫度變化控制閥門開關，起到阻汽排水作用。有開閥溫度低于飽和溫度15℃和30℃兩種膜盒供選擇。
進口膜盒式蒸汽疏水閥（蒸汽壓力平衡式）是目前上zui常用的*節能型疏水閥。膜盒式蒸汽疏水閥的反應非常靈敏，工作時閥前存有高溫凝結水，無蒸汽泄漏，節能*。
膜盒式在現如今蒸汽管線中是代替低壓（壓力在PN25以下）熱動力（圓盤式）疏水閥或（壓力在PN16以下）雙金屬片式疏水閥的理想替代品。
進口膜盒式蒸汽疏水閥Bellows Trap
The main acting unit of bellows trap is metal bellows, which is filled with a type of liquid with gasification temperature lower than water’s saturation temperature. When the device just starts, there appears condensate with low temperature in conduits and the liquid in the bellows is in the condensed state. The trap is turned on. When the temperature of condensate water gradually goes up, the liquid in the bellows begins to vaporize and the pressure within it increases. Consequently, the film drives the valve core to move towards the closing direction. Before the condensate water reaches its saturation temperature, the trap is compley shut down. The bellows controls the opening and closing of valves in accordance with steam temperature changes so as to resist steam and discharge water. Available are two alternative bellows with opening temperature 15℃ or 30℃lower than saturation temperature.
Bellows trap (with balanced steam pressure) is presently the most commonly used advanced energy-saving traps all over the world. As they are sensitive with high-temperature condensate deposits in front of valves while operating, they boast of remarkable energy-saving effect with no steam leakage.
Bellows trap, among all existing steam pipes, are presently the ideal substitute of low-pressure (with pressure below PN25) hot motive (disc) traps or bimetallic elements traps (with pressure below PN16).
優點：
1、動作速度快，零泄漏。
2、結構簡單，維護方便。
3、部件全部采用合金處理的不銹鋼，耐磨，耐氣蝕，使用壽命長。
4、排空能力強，排水迅速，安裝方式隨意。
5、可以實現多個膜盒組合，適用于大的排量場合。
6、具有良好的排空氣性能，不怕凍，零泄漏，背壓率達到75%。
Merits
1.Quick acting speed and zero leakage.
2.Simple structure and convenient maintenance.
3.All components made of alloy-treated stainless steel, resistant to wearing, gas corrosion, long durability.
4.Good emptying capability with quick discharge and easy installation.
5.Capable of combination of multiple bellows, suitable for large discharge.
6.Good air discharge capability, with coldness resistance, zero leakage and backpressure of 75%.
技術參數/Technique parameter
| 殼體壓力等級 Shell pressure grade | 負荷泄漏率 Load leakage rate | 使用介質 Used medium | 允許背壓率 Permitted backpressure rate | 節能效果 Energy saving effect | zui大工作壓差 Maximum operating pressure differential |
| 1.6、2.5MPA | 0% | 蒸汽、凝結水 Steam、Condensate water | 75% | 優秀 Excellence | 1.6MPA |
| zui小過冷度 Minimum subcooled temperature | 排水方式 Drainage method | zui高允許溫度 Maximum allowable temperature | 排空氣裝置 Air exhaust system | 抗凍性 Freezing resistance | 抗水擊 Resist |
| 0℃ | 間接方式 Indirect way | 350℃ | 自動 Automatic | 優秀 Excellence | 適應 Adaption |
主要零件材料/The materials of primary accessories
| 零部件名稱Part and component name | 材質Material |
| 閥體、閥蓋Valve body、Valve cover | 鍛鋼、不銹鋼Forged steel、Stainless steel |
| 膜盒Bellows | 哈氏合金Hasloy alloy |
| 閥座Valve seat | STL合金STL Alloy |
| 過濾網Filtrating screen | 不銹鋼Stainless steel |
