阀壳

According to the structural feature of parallel single disk gate valve,the strength and rigidity of body will be calculated with finite element method,and with cylindroid shell theory .

根据主闸阀结构特点，分别用有限元法和椭圆柱板壳理论公式计算了阀体的强度与刚度，并进行了分析对比，同时对闸板的刚度进行了校核。

In order to endure certain external pressure and seal well, the stainless steel spherical shell is designed and manufactured.

为了能承受一定的外部压力并很好地实现密封，设计并采用粘性介质压力成形工艺制造了不锈钢球壳阀芯。

As the complete characteristic curves of reversible pump turbine are often used to calculate the instantaneous parameters, this paper studies the characteristic curve and the wicket closure and opening law in pumped storage plants.Chapter 1 presents the importance and the necessity of this study and reviews the previous related research on hydraulic transient process and valve regulation in pumped storage plants.Chapter 2 analyzes the six collected characteristic curves of reversible pumped turbine and studies their diversification from the point of view of specific speed. The six collected discharge and moment curves with maximum efficiency have been fitted to piecewise continuous curves. This curve-fitting procedure is listed.Chapter 3 takes Liyang Pumped storage plant as an example and analyzes the effect of different characteristic curves on regulation guarantee parameters and the variety of its trochoid during the same operation status.Chapter 4 takes three pumped storage plants with different heads as examples and studies the characteristic of coordinated closure with wicket gate and ball valve and its effect on dynamic pressure in the spiral case, inlet pressure in the draft tube and the rise of rotating speed.Chapter 5 summarizes this paper and point out what should be done in the future research.

由于在过渡过程分析计算中，需要频繁利用可逆式机组的全特性曲线推求机组的瞬时参数，所以本文就特性曲线及关闭规律问题进行了研究，其主要内容如下：第1章，指出本文研究的意义和目的，回顾前人对水力过渡过程、抽水蓄能电站及阀调节的研究成果，在此基础上提出本文的研究内容；第2章，针对收集到的六套特性曲线，从比转速的角度出发来研究可逆式机组特性曲线的变化规律；并对六套曲线的最高效率流量和力矩曲线进行分段拟合，得到各分段函数的具体形式，再通过举例说明最高效率曲线的拟合步骤；第3章，以溧阳抽水蓄能电站为实例，分析讨论不同比转速特性曲线对调保参数造成的影响及对于相同工况其轨迹线的变化；第4章，结合高、中、低三水头段抽水蓄能电站，在导叶直线关闭的基础上，研究导叶与球阀协联关闭规律的特点及对蜗壳动水压力、尾水管进口压力及转速上升造成的影响；第5章，总结全文，提出今后研究的重点和方向。

Foot Valve Conversion –Foot valve screen housing assemblies are available to convert ball check valves to foot valves in the field.

底阀连接–可提供底阀滤网壳组件在现场将球形止回阀转换为底阀。

Foot valve screen housing assemblies are available for the field conversion of PVC and CPVC TU ball check valves in sizes 1/2"- 4".

可提供底阀滤网壳组件，用于现场更换通径DN15 - DN100的PVC和CPVC材质的TU球形止回阀。

At this time, is full of water pumps, if the long run, would lead to rising temperature in the pump, pump shell, the bearings will be fever, severe heat may make the body deformation, known as the "stuffy head," at this time Head to the maximum value, when the valve to gradually open, traffic will gradually increase, shaft power also slow the increase.

此时水泵里是充满水的，如果长时间的运行，会导致泵内温度不断升高，泵壳，轴承会发热，严重时可能使泵体热力变形，我们称为&闷水头&，此时扬程为最大值，当出水阀逐渐打开时，流量就会逐渐增加，轴功率亦缓慢的增加。

A regulation valve of a two-stage turbocharging system is arranged into the high pressure turbine volute to reduce the system sizes. Matching calculations for the turbocharging system and a diesel engine are made. Calculations in designing of two turbine volutes and regulating valve were taken. Experiments are conducted with the designed system.

为获得结构更为紧凑的二级增压系统，提出了将调节阀集成在高压级涡轮壳内部的二级增压系统结构方案，进行了增压系统与柴油机的匹配计算、两个涡轮壳的设计计算、调节阀计算以及流动分析，并对所设计的二级增压系统进行了试验研究。

Operation analysis and investigation show that it is caused by the inappropriate design of hot vapor bypass control system, so the revamping has been carried out as follows: The diameter of hot vapor bypass pipeline has been enlarged from DN 40 mm to 80 mm, and the pressure difference of hot vapor bypass adjusting valve decreased from 50 kPa to 35 kPa; A vent pipeline for non-condensable gas fro.

改造的措施主要有：增大了热旁路管道的直径(由DN40mm增大到DN80mm)，并降低了热旁路调节阀的压差取值(由50kPa降低到35kPa)；增设一条自冷凝器壳程出口至回流罐的不凝气放空管道；对脱丁烷塔分程控制系统进行了改造，即将调节器输出信号的0-45%，55%%-100%分别用于控制热旁路调节阀和放空阀。

Fill shell – Feed enters the shell side via lower feed manifold and exit the unit via top backwash discharge valves.

填充壳–给水通过低位给水歧管进入壳的一面，并通过上位反冲洗排出阀流出单元。

Fill lumen – Feed continues to enter the shell side via lower feed manifold, however, top backwash discharge valve is closed and filtrate exhaust valve is opened.

填充内腔–给水通过低位给水歧管持续进入壳侧，然而上位反冲洗排出阀关闭且过滤物排出阀开启。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。