A valve installed in the wellhead assembly to provide access to the casing annulus of non-producing casings.
安装在井口装置中的一个阀。它提供通向非生产套管的套管环形空间的通路。
PCTH tested valve has the function of being open state constantly and that keeping on open after annulus pressure relived out makes it much handy and be liable to be used.
PCTH测试阀可实现持开的功能，环空泄压后仍能保持开启状态，使用起来更加方便、灵活。
Conclusion: It is difficult to place prosthetic valve in routine sequence of valve replacement in patients with small aotic annulus and perivalvular leakage and hemorrhage of aotic incision may occur.
结论：小主动脉瓣环者，如果按照常规瓣膜替换顺序，将带来瓣膜座环困难、瓣周漏、主动脉切口出血等并发症。
Without keeping annulus pressure to static and instead of special metering by simple mechanical pressure ba lance structure, this valve is conducted by annulus pressure.
该阀采用环空外压操作测试阀的开关，不需要保压，而且采用简单的机械压力平衡机构代替了专用计量套。
Many pressure dominated testing valve is through pumping of relieving annulus pressure to realize open or shut down hole test valve and keep annulus pressure for certain all the time.
许多种压控测试阀均是通过环空加泵压打开，泄掉泵压关闭，开井过程中环空始终保持一定的开启压力。
Ortherwise, the eccentric gas anchor, gas lift valve and surface check valve are installed to automatically unload the gas from the deeper layer and annulus between the tubing and the casing.
大气量时应用偏心气锚安装气举阀与地面单流阀两步卸气，实现了下部产层和油套环空自动卸气。
The injection mandrel is equipped with a port - and check-valve system to direct fluid pumped down the annulus or injection line into the production conduit.
配注器装有孔口阀和单向阀系统，使泵入的流体沿环空向下或沿注入管线向下进入生产导管。
Objective to summarize the experience in treating mitral insufficiency (mi), due to secondary annular dilation in the posterior portion of the annulus with mitral valve reconstruction.
目的总结二尖瓣后环缝缩治疗二尖瓣关闭不全(MI)的临床经验。
The ablation target site was the isthmus between tricuspid valve annulus and inferior vana cava.
位于三尖瓣环和下腔静脉口间的峡部为消融部位。
The leaflets were sewn to the normal valve annulus;
将切下的瓣叶缝合于正常三尖瓣环上；
The leaflets were sewn to the normal valve annulus;
将切下的瓣叶缝合于正常三尖瓣环上；
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