进口抽汽止回阀，气动快速关闭逆止阀用途慨述 Overview of use

抽汽止回阀（气动快速关闭逆止阀）抽气止回阀是汽轮发电机组的配套产品。是保护汽轮发电机组的专用快关阀门，其作用是防止汽轮机组在突然甩负荷时汽轮机内压突然降低，抽汽管和各种热器内蒸汽倒流入汽轮机内造成在每分钟3000多转高速旋转的汽轮机叶片突然打反车运转，而造成将汽轮机叶片打碎，毁坏汽轮发电机的恶性事故，并防止加热器系统管道泄露使水从抽汽管路进入汽轮机内而发生水击事故 RETZExtraction check valve (pneumatic quick closing check valve) The extraction check valve is a supporting product of the steam turbine generator unit. It is a special quick closing valve for protecting the steam turbine generator unit. Its function is to prevent the sudden reduction of the internal pressure of the steam turbine during the sudden load rejection of the steam turbine unit, and the backward flow of steam in the extraction pipe and various heaters into the steam turbine, resulting in the sudden reversal of the turbine blades rotating at a high speed of more than 3000 revolutions per minute, resulting in a vicious accident of breaking the turbine blades and damaging the turbine generator, And prevent water hammer accident caused by leakage of heater system pipe, which makes water enter the turbine from steam extraction pipe

技术规范 technical specifications

设计制造标准：ASME/ANSIB16.34、E101、JB/T3595

结构长度标准：JB/T3595、ASME/ANSIB16.10、GB/T12221

焊接端或法兰标准：GB/T12224、ASME/ANSIB16.25、GB/T9113、JB/T79~JB/T82

试验验收标准：JB/T9092、JB/T3595、ASME/ANSIB16.34、E101

进口抽汽止回阀，气动快速关闭逆止阀结构说明Structureelucidation

本阀由阀门本体、快速助关装置与控制系统等几部分组成 The valve is composed of valve body, fast closing aid and control system

1、阀瓣采用大角度斜置，缩短启闭行程，减速少关闭时间，减速轻冲击，保护设备本身和管道安全，并有气压缸助关，使饲鳝在0.5秒的时间内实现快速关闭 The valve clack is inclined at a large angle to shorten the opening and closing stroke, reduce the closing time, reduce the speed and impact slightly, protect the safety of the equipment and pipeline, and have a pneumatic cylinder to help close, so that the feeding eel can be closed quickly within 0.5 seconds

2、阀瓣设计为经摇杆与阀杆活动连接，可与阀瓣密封面自对对中，保证密封面吻合 The valve clack is designed to be movably connected with the valve stem through the rocker, which can be self aligned with the sealing surface of the valve clack to ensure that the sealing surface matches

3、密封副采用硬面接触，洒搓密封面使用高耐磨材料硬质合金堆焊加工而成，提高了阅缚在高流速的介质下的耐磨性和冲刷性能。并且提高了阔门在高温，高压的工况下的密封性能。微特的斜锥密封面结构，密封可靠，启闭自如，不会因快速关闭，高压而出现阀鬓咬死现象。密封副在启闭时无摩擦，开启即分离，关闭接触即密封，并且可自动补偿密封面长期使用导致磨损，从而大大的提高了阀门的使用寿命 The sealing pair adopts hard surface contact, and the rubbing sealing surface is made of hard alloy surfacing with high wear-resistant material, which improves the wear resistance and scouring performance of the reading binding under the medium with high flow rate. It also improves the sealing performance of the wide door under high temperature and high pressure. The micro special bevel sealing surface structure ensures reliable sealing, easy opening and closing, and will not bite the valve due to fast closing and high pressure. The sealing pair has no friction when opening and closing. It is separated when opening and sealed when closing contact. It can automatically compensate the wear caused by long-term use of the sealing surface, thus greatly improving the service life of the valve

4、阀体内腔彩用流线型设计，流通能力大，减小阀门阻力 The inner cavity of the valve body is designed streamline, with large flow capacity and reduced valve resistance

5、执行机构为弹簧复位式气缸，并与阀门关闭件独立，执行机构故障不影响关闭件动作 The actuator is a spring return cylinder and independent of the valve closure, and the actuator failure will not affect the action of the closure

6、关闭件开启设有限位机构，避免开启过位造成损坏 The closing element is equipped with a limit mechanism to avoid damage caused by over opening

执行器结构说明和工作原理Actuator structure description and working principle

本阅可采用压缩空气与液压油作为控制动力，气源压力∶0.4~0.6MPa（或液压压力∶0.7~1.0MPa）逆止阀为摇板式，其结构及气（液）动控制见附图。

The valve can use compressed air and hydraulic oil as control power. The air stource pressure:0.4~0.6MPa(or hydraulic pressure:0.7~1.0MPa).The check valve is a swing plate.Its structure and pneumatic ((hydraulic) control are shown in the attached figure.

气路系统工作原理及示意图Working principle and schematic diagram of air circult system

压缩空气经“直通球阀”，“空气过滤减压装置”接“电磁二位五通阀"及一个"手动换向阀"，控制压缩空气的通断，正常运行时，上述三阀均处于“通”状态，操纵气缸里的活塞被压缩空气顶出，带动强关机构与逆止阀转轴的啮合片脱开，此时抽气止回阀作为一只自由摆动的摇板阀工作。当汽轮机的危急保安系统动作，或加热器出现高水位时，电磁阀动作，压缩空气源被切断，活塞下腔压缩空气排出，活塞杆受弹簧力作用而下移，带动强关机构逆止阀转轴压制在使阀瓣关闭的位置，于是强迫切断流通通道  Compressed air passes through "straight ball valve", The "air filtering and pressure reducing device" is connected to the "electromagnetic two position five way valve" and a "manual reversing valve" to control the on-off of compressed air. During normal operation, the above three valves are "on" In the state, the piston in the control cylinder is ejected by compressed air, which drives the strong closing mechanism to disengage from the mesh plate of the check valve spindle. At this time, the air extraction check valve works as a free swinging rocker valve. When the emergency security system of the turbine acts, or the heater has a high water level, the solenoid valve acts, the compressed air source is cut off, the compressed air in the lower chamber of the piston is discharged, and the piston rod moves down under the spring force, driving the spindle of the check valve of the strong closing mechanism to press the position where the valve clack is closed, so that the flow channel is forced to be cut off

机组正常运行时，可手动操作试验阀进行试验，此时泄去活塞下部的压缩空气，观察逆止阀阀位变化情况，从而确认强关装置的动作是否可靠 During the normal operation of the unit, the test valve can be manually operated for test. At this time, the compressed air at the lower part of the piston can be released, and the change of the check valve position can be observed to confirm whether the action of the forced closing device is reliable

零部件材料Parts List

旋启式结构及材料表 Swing structure and material list

升降式结构及材料表 Lifting structure and material list

安装维护与使用注意事项Precautions for installation，maintenance and use

1、本阀门在电厂安装时进出口两端应处同一水平位置，运行中可压紧两端填料以防泄露，并微性能试验以防转轴卡涩，周边应留有足够空间，以便于拆装检测，并使介质流向与阀门上标志箭头方向一致。

2、阀门在吊装过程中，应小心轻放，避免碰伤。

3、安装前检查阅门的内腔和密封面，不允许有污垢附着，连接管道内须清除干净，不得有异物存在。

4、填料为柔性石墨材质，热膨胀性能好，故在冷态时不要压得过紧，更换填料时，注意避免损伤阀杆表面。

5、本阀门尉带气动控制原理图中的气缸，电磁阀，手动换向阀，球阀，空气过滤减压装置，行程开关及管路附件。用户可根据现场实际情况安装（连接管线，支架由用户自理）。

6、阀门应存放在干燥的室内，放置整齐，不允许露天存放，以防损坏和腐蚀。

7、若阀门长期存放，应定期检查，并在加工面上涂防锈油。

8、注意∶本概门的助关装置中有弹簧，用户如需拆卸维修时应准备相应规格的不同长度的螺栓，逐个替换原有螺栓，拆卸时使弹簧蓄积的能量逐渐牵放，防止弹簧能量急剧释放造成事故。

1. When the valve is installed in the power plent, both ends of the inlet and outlet sshall be at the same horizontal position. During the operation, the packing at both

ends can be pressed to prevent leakage, and the performance test shall be conducted to prevent the shaft from jamming. There shall be enough space around to facllitate the disassembly and inspection,and the flow dlirection of the mediumshe valive.

2.During the hoisting process, the valve shall be handled with care to avoid darnage.

3.Before installation, check the inner cavity and sealing surface of the valve, no dirt is allowed to attach, and the connecting pipe must be cleaned without foreign

matters.

4.The packing is made of flexible graphite with good thermal expansion performsance, so do not press too tightly when it is cold. When replacing the packing, pay

attention to avoid damaging the surface of the valve rod.

5.The valve is attached with cylinder, solenoid valve, manual directional valve, ball valve, air filtration pressure reducing device, travel switch and pipeline

accessories in the pneumatic control schematic diagram. The user can install accolrding to the actual situation on site(connect the pipeline, and the support shall be taken care of by the user).

6.The valve shall be stored in a dry room in order to prevent damage and corrosion.

7.If the valve is stored for a long time,it shall be inspected regularly and the processing surface shall be coated with antirust oil.

8.Note: there is spring in the closing aid of the valve. If the user needs to disassemble and maintain, he should prepare bolts of different lengths of corresponding

specifications, replace the original bolts one by one, and release the accunnulated energy of the spring gradually during disassembly, so as to prevent accidents caused by rapid release of spring energy.

可能发生的故障和消除方法Possible faults and elimination methods

1、中法兰和阀盖之间、阀杆孔两测端、填料涵泄露。

A∶螺栓没的拧紧或松紧不均，重新调螺拧紧螺栓。

B∶垫片或填料损坏，应更换垫片或填料。

2、密封面泄露

A∶密封面间有脏特，应该清洗。

B∶密封面擦伤、磨损，应重新研磨加工，如缺陷严重应重新堆焊加工。

3、执行器故障。

A∶执行器活塞密封损坏，跟换O型圈与密封件。

B∶执行器上下活塞杆处泄露，上下盖与活塞杆处密封损坏跟换O型圈与密封件。

4、电器部分控制失灵

A∶由于振动使触头及接线点松动，检查中间继电器交流接触器的触头，行程开关搅块和其他触头及接线点。

B∶电磁铁不动作电磁阀线圈烧坏，更换电磁阀线圈。

1.Leakage between middle flange and bonnet, twvo measuring ends of stem hole and packing culvert.

A: if the bolts are not tightened or not evenly tightened, readjust the bolts and tighten them. 

B: if the gasket or packing is damaged, replace it. 

2. Leakage of sealing surface

A:there is dirt between the sealing surfaces,which should be cleaned.

B:if the sealing surface is scratched or worn, it shall be grinded again. If the defect is serious, it shall be overlaid again. 

3. Actuator failure.

A: the actuator piston seal is damaged. Replace the O-ring and seal.

B: there is leakage at the upper and lower piston rods of the actuator, and the seals at the upper and lower covers and piston rods are damaged and the O-rings and

seals are replaced.

4.Control failure of electrical part

A: the contact and connection point are loose due to vibration. Check the contalct, stroke switch bump block and other contacts and connection points of the AC contactor of the intermediate relay.

B:the solenoid coil is burnt out when the electromagnet does not act. Replace the solenoid coil.