Makers of quality custom molded fiberglass products for water and wastewater treatment . product range includes flumes , shelters , weirs , odor control hoods and baffles -销售炉头，阀门，调节阀，助燃风机及其它燃油-空气调节阀，节流阀，切断阀，减压阀等产品。
The so / sb shutoff regulator is used in the gas line to automatically shut off the fuel when the combustion air or any remote signal pressure drops below a predetermined limit Sb切断阀用于燃气管线自动切断燃料，当燃烧空气或者任何遥控信号的压力低于预设定极限值。
Pipe rupture valve is able to close itself in the event of failure in the main cylinder line or where the down speed exceeds allowable limits in the hydraulic elevator system 限速切断阀是液压电梯中的安全保护阀，它能够在液压电梯系统出现异常情况时关闭系统，起到保护作用。
N series of wear - proof thermocouples are composed of ceramic thermocouple , cut off value and wear - proof head etc . with the advantages of high temperature - resistant and corrosion - proof H - wr - n系列耐磨热电偶，主要采用装配式热电偶切断阀耐磨头等结构组成，具有耐高温耐腐蚀的特点。
The solution to the problems existing in the speedy cutting off valve is put forward . every movement of the speedy cutting off valve can be implemented with simpler operation and increased system performance 在保证实现快速切断阀各项动作的基础上，消除了有害作用，操作更为简单，提高了系统性能。
In chapter 1 the principle and the research status of the pipe rupture valve and the requirement of the pipe rupture valve in the european hydraulic elevator manufacture and secure installation standards ( en81 - 2 ) are also introduced 本文在第一章对限速切断阀的原理进行了简介，并分析了国内外的研究现状，以及介绍了欧洲《液压电梯制造与安全安装规范》中对限速切断阀的要求。
These simulation results can be used to analyze the operating conditions and environment requirements for nominal working . in chapter 5 the experiment rigs are introduced first . because the experiments would concern many performances of the pipe rupture valve , there are two different sets of experiment rigs 第五章首先介绍了限速切断阀的实验方案与实验台架，由于本实验涉及限速切断阀的较多性能，因而采用了两种不同的实验设备。
Then the results of the experiment is analyzed and compared with the simulation results . on the one hand , it satisfies the simulation conclusions ; on the other hand , it draws some useful conclusions . finally , ensures whether the valve satisfies the requirements of the en81 - 2 然后分析了实验结果，并对动态实验数过与仿真结果进行了对比研究，一方面验证了仿真的结论，一方面得到了一些有价值的结论，最后分析实验结果，考核该阀是否符合欧洲《液压电梯制造与安全安装规范》中对限速切断阀的要求。
3 . improve the drive system of speedy cutting off valve in trt after investigating the operation of the trt system of the blast furnace and analyzing the structure of the speedy cutting off valve , the problems of the speedy cutting off valve are described from the viewpoint of system function . the new principle solution which contents the required function is determined by the mapping relation between function and effect in fee model , then the function structure is improved by trimming 3 、快速切断阀驱动系统的改进设计对trt系统和快速切断阀结构进行了深入研究，从系统功能的角度描述了快速切断阀存在的问题；按照需求功能通过fee模型中功能与效应映射关系，确定满足需求功能的效应，产生了新的原理解；并应用裁剪对功能结构进行改进，提出了快速切断阀存在问题的解决方案。
Using matlab , the step response characteristics of the valve in the elevator system is simulated , comparing the effect of its performance with different structure parameters of the pipe rupture valve , such as hydraulic resistance , diameter of the valve , and spring rigidity , and comparing the valve ' s dynamic performance under different operating conditions , such as environment temperatures , number of passengers , and emergencies of the hydraulic system , so the paper offers a general and systematic analysis for the pipe rupture valve of the elevator system 另外，在液压电梯不同的工况下，对该阀的动态性能进行了仿真对比研究，如不同环境温度、不同乘客人数、不同液压系统意外，以及不同的油液体积弹性模量，比较全面系统的分析了限速切断阀在电梯系统中的性能，根据这些仿真结果，可以分析该阀正常工作的工况要求和环境要求。
