valve bonnet seal

基本解释

The valve bonnet may now be removed. There may be slight leakage as the backseat does not provide a drip-tight seal.
现在可以拆卸阀盖。如果后座无法提供无滴漏密封，则会有轻微的泄漏。
As a result of continuous design improvements, Velan is offering live-loading of bonnet "take-up" bolting as a standard pressure seal valve feature.
由于不断改进设计，Velan的“take-up”螺栓阀帽动负载成为标准的压力密封阀门的特点。
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。
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