C．围焊结合式（SEAL WELDED BONNET）D．压力密封式（PRESSURE SEAL BONNET）E．由令结合式（UNION TYPE）（7）阀结构特殊需求依使用温度，场所不同，而有所特殊的要求列举如下：A.
4
?压力自紧密封阀盖
(6)一般情况下，压力等级超过(含有)Class 900，且DN≥50的阀门采用 压力自紧密封阀盖 ( Pressure Seal Bonnet );压力等级低于(含有)Class 600的阀门采用螺栓连接阀盖(Bolted Bonnet)，对有些要求严格防止泄漏的工况，可以考虑采用焊接型阀盖...
双语例句
1
The same force tends to reduce the seal on the pressure side with the result that bonnet cavity and the valve stem packing are nearly always subjected to maximum pipeline pressure.
而压力侧以相同的力削弱了密封，这样使阀盖腔室和阀杆填料几乎总是承受最大管道压力。
2
Carbon, Alloy or Stainless Steel, Pressureseal or Bolted Bonnet Provision for seal Welding on Bolted Bonnet Valves.
碳钢，合金钢或不锈钢，压力密封或螺栓阀帽用于焊接在螺栓阀帽阀门上阀座的设备。
3
Use back seal design, can replace top seal parts under pressure. Entirety of non-rising bonnet design, have compact structure.