堵平衡孔法减少轴向负推力的应用

汽轮机转子轴向推力是汽轮机安全运行的重要参数，机组设计时为了减少正向轴推力。通常在高压转子各级轮盘开有平衡孔，机组运行一段时间后，许多指标便会偏离设计值，转子出现负向推力，影响机组的安全运行。对茂名热电厂4号汽轮机转子轴向负推力大的问题进行分析和核算，并提出用堵平衡孔法进行改进及总结改造结果。     

略阳电厂5号汽轮机降低轴向推力恢复铭牌出力试验研究

分析了略阳电厂5号汽轮机运行中推力瓦温度超标的原因,对机组热力特性及轴向推力进行校核计算,在此基础上提出降低轴向推力及机组带额定负荷的可行性方案,实施后可使机组在额定工况下的推力瓦温降低在合格范围以内。     

某厂350MW汽轮机推力轴承温度高原因分析及处理

针对某厂350MW超临界汽轮机投产后,随着机组负荷的增加,其推力轴承工作瓦块温度持续升高,并发生了两次磨损事故,严重影响汽轮机安全运行的现状,通过对汽轮机制造、安装以及机组保护方面检查,确认汽轮机轴向推力设计有误,制造厂根据重新计算结果对高压平衡鼓进行了车削处理,并对机组轴向位移、轴承温度保护进行了完善,现机组运行正常.     

给水泵汽轮机推力瓦磨损的原因及对策

针对某330MW供热机组跳闸后给水泵汽轮机推力瓦损坏故障,从推力瓦工作失常、汽轮机叶片结垢、给水泵异常运行、进汽量增大、汽轮机水冲击和热工保护系统等方面对其进行了分析。结果表明:给水泵汽轮机运行中进汽量骤增、汽轮机转子局部发生水冲击导致的转子轴向推力增大,热工保护逻辑不完善造成磨损进一步加剧。从系统设计和运行方面提出了处理措施和防治对策。     

粤泷电厂纯凝式机组供热改造

介绍了粤泷电厂2×135MW纯凝式机组供热改造的实施方案.在不改变汽轮机通流结构的前提下,采取在主蒸汽管道、低温再热蒸汽管道和高温再热蒸汽管道上开孔抽汽降温降压的供热改造方案.经汽轮机厂家进行强度和机组轴向推力校核,供热抽汽改造后,汽轮机高压5～8级、中压5～10级动叶片安全性均合格,轴承推力及比压均在允许范围内.在满足用户用热需求的同时,减少SO2、NOx、烟尘的排放.     

汽轮机推力轴承温度高原因分析与处理

某热电联产汽轮机推力轴承温度高 ,故障时有发生 ,直接影响机组安全经济运行。作者通过对检修中测量结果的认真分析 ,指出了导致推力轴承温度高的若干原因 ,并进行了相应的处理。机组实际运行表明 :该处理措施有效降低了推力轴承温度 ,满足运行要求。还从多方面给出了防止推力轴承温度高的建议。     

汽轮机推力轴承温度高原因分析及处理

某热电联产汽轮机推力轴承温度高,故障时有发生,直接影响机组安全经济运行。作者通过对检修中测量结果的认真分析,指出了导致推力轴承温度高的若干原因,并进行了相应的处理。机组实际运行表明：该处理措施有效降低了推力轴承温度,满足运行要求。还从多方面给出了防止推力轴承温度高的建议。     

660MW超临界机组轴向位移异常事故分析及防范

汽轮机转子由推力轴承轴向定位,轴向位移反映其轴向推力的变化情况,是汽轮机通流部分动静间隙安全可靠的保障。某660 MW超临界机组在运行过程中多次出现轴向位移突然闪跳甚至导致机组跳闸的现象。通过对机组轴向位移历史数据的分析,对现场高压调门与喷嘴室间导汽管上的疏水管阀布置进行检查,找出事故由高压调节阀CV1开出后导汽管冷水汽进入汽机高压缸通流部分造成轴向推力突然增大引起。针对此影响机组运行的重大安全隐患,提出了防范措施,为类似机组安全运行和维护提供警示和参考。     

600MW汽轮机调节级推力的计算方法及机组推力分析

本文首先指出反动式汽轮机推力计算是关系到机组运行安全性的重要问题之一,然后列举和分析优化设计的600MW汽轮机推力计算及有关问题、计算方法及主要计算结果。着重介绍调节级推力的计算程序及其对总推力的影响。     

某300MW汽轮机组推力瓦磨损问题分析及处理

针对推力瓦磨损造成设备损坏的问题,以某300 MW汽轮机推力瓦磨损事件为例,结合推力瓦工作原理对案例进行分析,得出主要原因为机组在严重偏离设计工况下运行,轴向推力超出推力瓦平衡范围,机组负荷多次振荡,加剧了推力瓦磨损,并采取了更换磨损瓦块等一系列措施。     

Influence of the Operational Wear of the Stator Parts of Shroud Seals on the Economic Efficiency of the Steam Turbines

During the operation of steam turbines under transient conditions, due to different thermal expansion of the stator and rotor parts in the radial and axial directions, the clearances fixed in the course of assembling the seals of the flow path change, which causes rubbing in the seals and the wear of the latter. This inevitably increases the leakages through the seals. A particularly large difference in the relative axial and radial displacements of the rotor and stator parts is observed during the turbine start-ups when the difference in their temperature expansion is maximal. Upon the turbine stops, the turbine shafting runs down freely, as a rule, passing through all critical speeds at which the amplitude of the shafting oscillations reach their peak values, which also leads to seizures in the seals and their wear and tear. The seizures in the seals may also be a consequence of the eccentricity between the rotor and stator caused by the thermal strain of the stator, incorrect choice of the clearances, floating-up of the rotor in the bearing, and many other factors. Recently, standard shroud labyrinth seals are being replaced in the steam turbines by seals with honeycomb stator inserts, the design of which allows the ridges to cut into the honeycomb surface without damaging the former, which allows fixing a radial clearance in the seals of 0.5 mm. On the honeycomb surface where the ridges touch it, grooves are cut through. The wear of the shroud seals reduces the efficiency of the steam turbines during the operation to the greatest degree. However, by the present there have been no exact quantitative data available on the change in the leakage through the worn-out honeycomb seals. The paper presents the results of comparative experimental studies on the flow and power characteristics of seal models with smooth and honeycomb stator parts for various degrees of their wear. The studies showed that the leakages through the worn-out stator parts of the honeycomb seals increase approximately 1.7 times slower than under the similar wear of the ridges of conventional straight-through seals with smooth stator parts. However, this gain in efficiency achieved by replacing the standard smooth-wall seals with the honeycomb seals must be necessarily correlated with the measurement data on the nonconservative shroud forces in conventional axial-radial seals with smooth stator surfaces with a radial clearance of 4 mm, which is almost seven times lower than that in the honeycomb seals with a radial clearance of 0.5 mm. From the results obtained in the work, it follows that the installation of honeycomb shroud seals instead of traditional ridge seals in the high-pressure cylinders (HPCs) of the steam turbines for subcritical steam parameters with high-vibration-resistance rotors that have a sufficient margin of resistance to self-oscillations is undoubtedly advisable from the point of view of increasing the economic efficiency of the turbines. However, the use of honeycomb shroud seals with reduced radial clearances in the HPC parts of the steam turbines for supercritical steam parameters requires special cautiousness, since it is in the area of small clearances that the maximum nonconservative shroud forces capable of causing auto-oscillations of the shafting are observed and these forces are maximal precisely at high pressures.     

汽轮机数字电液控制系统仿真器的设计

随着电力系统的飞速发展,数字电液控制系统（DEH）成为当今汽轮机特别是大型汽轮机必不可少的控制系统。针对当前电厂汽轮机机组的实际要求,设计了汽轮机DEH控制系统仿真器。该仿真器通过模拟汽轮机机组的调节特性。代替汽轮机完成与DEH系统的信息通讯。运行时能动态显示各种运行参数及开关量等信息。阐述仿真器的硬件设计和软件设计方案,以及采取的抗干扰措施。电路设计简单,使用方便。该仿真器具有较好的通用性,安全又省时,灵活性大,有一定的发展前景。     

基于模糊数风险分析法的汽轮机自启动技术研究

设计了一套基于模糊数风险分析法的智能汽轮机控制系统：通过对汽轮机的运行特点进行研究,将汽轮机的启动过程划分为若干个步序依次执行;采用模糊数相似度风险分析法,对汽轮机启动过程中的风险进行预估和管控,并结合运行人员经验,以确定是否执行下一步序,据此规划适宜的启动路径。该技术实现了采用非热应力模型的汽轮机自启动控制,对国产汽轮机自启动技术的研究与应用具有一定的参考价值。     

600 MW机组汽轮机的寿命管理研究

阐述了汽机寿命损耗的计算模型,以北仑发电厂600MW汽轮机寿命管理为例,分析了影响汽轮机寿命的主要因素,阐明了汽轮机寿命管理的主要手段,可为机组运行优化提供指导,同时也可为其他类型汽轮机的寿命管理提供借鉴.     

Ways for Improving Efficiency and Reliability of Steam Turbines at Nuclear Power Stations

The current state and ways for improving the effectiveness of steam turbine units at nuclear power stations (NPS) are examined. The specifics of NPS turbines is described. The comparison of NPS steam turbine performance with the performance of steam turbines at thermal power stations (TPS) demonstrates that power units of NPSs are much poorer in effectiveness due to relatively low steam conditions at the inlet and the presence of wet steam already in the first stages of turbines. A decrease in the relative internal efficiency of NPS turbines results from the enhanced negative effect of wetness in the expansion process: in modern NPS turbines, more than two-thirds of the heat drop is spent in the two-phase region, while less than one fourth in TPS turbines. It is demonstrated that the effectiveness of NPS steam turbine units can be increased drastically in the future only through a considerable rise in the turbine inlet steam conditions. This can be achieved by using a heat carrier at supercritical conditions in the NPS reactor. The dependence of the effectiveness of NPS modern turbines on the turbine inlet steam conditions in the applicable pressure ranges of the saturated steam and vacuum in the condenser, as well as on the turbine exhaust area, is examined. For a 1000 MW turbine, increasing the inlet pressure from 6.0 to 8.0 MPa raises the turbine power and efficiency by 3.5%. At a condensing turbine outlet pressure ranging from 2.5 to 7.5 kPa and a constant velocity downstream of the last stage, the turbine power and efficiency can be increased by 7%. The importance of the exhaust area for the turbine effectiveness is revealed. Alternative designs of the flowpath in a low-pressure cylinder are analyzed. A unique configuration of a steam turbine unit with two-stage moisture separation is proposed. The comparison of high-speed turbines with low-speed ones was performed. It is demonstrated that the efficiency of the examined turbines is nearly the same within the accuracy of design calculations and the test results, and it is slightly higher for low-speed turbines due to lower losses with outlet velocity.     

精确计算汽轮机运行主蒸汽流量的一种可行方法

大功率汽轮机的运行主蒸汽流量都不能直接测定,但它却是设备工作状态最重要的监视参量之一,因此应精确确定。基于汽轮机工作原理和大量的试验,提出一种特定机组专用的主蒸汽流量计算公式,先利用汽轮机再热蒸汽入口压力和温度测量值求得再热蒸汽流量,然后再用一组相关的参数测量值通过计算准确地求得主蒸汽流量。     

国产200MW汽轮机组调速系统故障试验分析与处理经验

针对国产２００ＭＷ汽轮机组液压式调速系统投产多年来经常发生卡涩、甩负荷不稳定运行的客观问题,对华能淮阴电厂２台２００ＭＷ汽轮机调速系统进行了综合治理和技术攻关取得了成功的经验,值得国产同类型机组借鉴。     

The concept of new-generation steam turbines for coal power engineering of Russia. Part 1. Economic and technical substantiation of the concept

Development of the concept of designing modern steam turbines and its application to turbines for ultrasupercritical steam conditions are considered. The results from predraft designing of a turbine for ultrasupercritical steam conditions with a capacity of around 700 MW in a two-cylinder version that corresponds to this concept are presented. Main problems relating to construction of such turbines under the conditions of Russia are analyzed.     

Extending the service life of steam turbines using the systems for cooling the thermally stressed parts of high- and intermediate-pressure cylinders

The problem of extending the service life of a large fleet of operating steam turbines is considered. A method for reducing the damageability of the most thermally stressed parts of steam turbines with capacities ranging from 100 to 800 MW is demonstrated. Data on putting in use cooling systems and on their effectiveness in solving the problem of extending the service life of such turbines are presented.     

国产引进型300MW汽轮机轴封系统的试验研究

介绍国产引进型３００ＭＷ汽轮机轴封系统的工作原理,针对其普遍存在的中热器真空不足、运行方式不合理、供汽自动调节性能不良而导致汽轮机真空严密性差、轴端冒汽、润滑油带水等一系列问题,通过对嘉兴电厂２台机组轴封系统的现场试验和理论分析,找到了问题的根本原因,经技术和运行优化,有效的邮机组运行的安全性经济性。