氮封阀作用的弹簧全启式阀，带有喷嘴型的阀座、 同阀座分开的阀体和放大了的出口支管。由于其开启高度较 大，因此其排放能力较高。在此开启高度下，所通过的介质排量是由阀座通道截面积而不是由阀瓣打开的环状间隙截面积 决定的。为了达到大的开启高度，既利用了增加介质冲击作 用面积的原理，又利用了喷出流束的反冲作用原理。

A spring full open safety valve with nitrogen sealing function, equipped with a nozzle type valve seat, a separate valve body from the valve seat, and an enlarged outlet branch. Due to its high opening height, its emission capacity is relatively high. At this opening height, the displacement of the medium passing through is determined by the cross-sectional area of the valve seat channel rather than the cross-sectional area of the annular gap opened by the valve disc. In order to achieve a large opening height, both the principle of increasing the impact area of the medium and the principle of recoil effect of the ejected flow beam were utilized.

所以能达到高排放能力还有赖于：由于阀座通道截面积没有因导向筋的存在而缩小，因而介质流动畅通；不仅在阀座 通道中，而且在阀瓣打开的环状间隙处都没有涡流现象。除此而外，阀体和出口支管的通道截面积都较大。由于排放能力高，阀的阀座通道截面积可以较小，从而使阀门易于密封。

So achieving high emission capacity also depends on: because the cross-sectional area of the valve seat channel has not been reduced due to the presence of guide ribs, the medium flow is smooth; There is no vortex phenomenon not only in the valve seat channel, but also in the annular gap where the valve disc opens. In addition, the cross-sectional area of the valve body and outlet branch pipes is relatively large. Due to its high emission capacity, the cross-sectional area of the valve seat channel of the safety valve can be smaller, making the valve easy to seal.

在通常的阀结构中，阀座做成与阀体分离的喷嘴形式。，所以闷座不受变形的影响。阀体与喷嘴之间的螺纹间隙的选择应使得喷嘴能够自由 膨胀而不受阀体变形的影响。对于在高温高压下使用的阀，采用"热阀瓣"并将其嵌入到阀瓣座中。喷嘴和'热阀瓣" 的尺寸和材料应选配得当，以使它们的热膨胀相同，不发生相对位移。

In typical safety valve structures, the valve seat is made in the form of a nozzle separated from the valve body., So the seat is not affected by deformation. The selection of thread clearance between the valve body and nozzle should enable the nozzle to expand freely without being affected by valve body deformation. For safety valves used under high temperature and pressure, a "hot valve disc" is used and embedded into the valve disc seat. The size and material of the nozzle and heat valve disc should be selected appropriately to ensure that their thermal expansion is the same and there is no relative displacement.

阀瓣的导向套与阀体的连接为非刚性的，并且不接触热 的或脏的介质，从而使阀容易开启和回座。阀杆和阀瓣之间通过淬火钢球来联接。这种机构能保证阀杆不受弹簧偏 斜的影响而自动对准中心，并且能防止阀瓣被卡住。

The connection between the guide sleeve of the valve disc and the valve body is non rigid and does not come into contact with hot or dirty media, making it easy for the safety valve to open and reseat. The valve stem and valve disc are connected by quenched steel balls. This mechanism can ensure that the valve stem is not affected by spring deflection and automatically aligns with the center, and can prevent the valve disc from getting stuck.