P型空压机喘振故障分析及对策

离心式空压机组在运行中容易产生喘振故障,喘振的发生往往由于空压机气体流量的减小等原因从而引起空压机叶片旋转失速。当空压机运行环境进一步恶化,空压机工作状态就由旋转失速进而发展为喘振,P型空压机是离心式空压机的一种,在投产初期常出现的喘振故障,针对喘振故障现象进行了原因分析,找出了预防喘振的控制方法,减少喘振故障的发生,有利于空压机在安全的状态下运行。     

空压机防喘振自动控制

介绍了离心式空压机产生喘振的机理,对喘振原因进行了分析.结合石钢公司2套制氧机组离心式空压机的工程设计、组态、防喘振控制的设计实例,分析了防喘振操作过程中容易出现的问题,对类似机组的DCS编程组态和操作控制具有一定的借鉴.     

宽厚板离心空压机喘振故障分析与对应措施

结合宽厚板离心空压机的现场运行实际,研究分析空压机发生喘振的原因,并制定相关对策保证空压机稳定顺行。     

TY-520/5.2-I型离心式压缩机喘振处理实践

TY-520/5.2-I离心式空气压缩机在运行过程中,由于工况的不稳定,引起机组进入喘振工作区, 严重时造成空压机停机,影响生产。以2013年9月发生的喘振为例,阐述离心式空压机发生喘振的原因及机组状况,分析发生喘振时的处理方法及防范措施。     

离心空压机喘振分析与技术改进

以喘振产生的原理排查喘振发生的原因,阐述喘振的危害和判断方法,分析了喘振的主要因素,从空压站、压风用户的工艺、设备和技术要求入手,对生产现场的工艺改进与措施、生产用风规律和生产模式进行掌控,实现离心式空压机喘振的有效控制;取得了较好效果,为解决离心式空压机振动异常问题提供了实例参考。     

23500m~3/h制氧机空压机组喘振的现象及分析

一台23500 m3/h制氧机组空压机发生多次喘振,通过分析,找出其原因是空气过滤器后消音器处滤网被柳絮等杂物堵塞导致空气流通面积减少,空压机吸入阻力增大。从5个方面采取措施,消除了喘振现象。     

制氧站空压机防喘振自动调节系统

详细论述了制氧站空分系统的空压机产生喘振的原因和防喘振仪控自动调节系统的控制原理、现场调整原则及调试方法，同时提出了在现场调试和系统投运时，保证仪控系统可靠的技术措施。     

酒钢21000m3/h制氧机防喘振保护控制策略

从离心式透平压缩机的调节和喘振保护理论出发,分析研究了大型进口透平空气压缩机的调节与喘振保护控制策略,结合酒钢21000 m3/h制氧空压机实际的生产工艺,对空压机的调节与保护的控制策略进行了设计优化。     

空分装置离心式空压机空气管道设计

离心式空压机的正常工作是保证整个空分装置稳定运行运行的关键,而工艺空气管道的设计又是空压机安全、正常运行的必要条件之一。着重介绍了空压机入口、出口以及防喘振管道设计过程中需要注意的问题。     

制氧空压机的防喘振控制

介绍了离心式空压机喘振现象的原因和可能对设备和生产过程造成的危害,分析了紫金铜业25 000 Nm3/h制氧装置空气压缩机的防喘振控制及其相应控制回路的构成、喘振控制线的确定以及运行时的加载等过程。     

稳定球团生产的若干设计问题

就链箅机-回转窑球团生产线设计中,各种贮仓和缓冲仓、各种旁通设施、关键设备进排料口的紧急出口以及风流系统的各种放散阀和兑冷热风阀的功能和设置进行了讨论。这些设施是稳定生产、避免发生重大设备事故、提高作业率、改善产品质量所必备的调节手段。     

Physical Processes Resulting in Geysers in Rapidly Filling Storm-Water Tunnels

Geysers, which involve the explosive release of water through vertical shafts connected to a nearly horizontal pipeline, have been attributed to either pipeline surge or the release of air. Laboratory experiments involving the release of a large entrapped pocket of air through a surcharged vertical riser indicate that the air can force water upward in the shaft but that a jet such as seen in video records of prototype systems does not form. This difference is attributed to processes that cannot be scaled down to the laboratory experiments. Data from a storm-water tunnel in Minneapolis that experienced a series of observed geyser events were analyzed. Measurements included pressures and velocity within the tunnel that can be correlated with observations on a videotape of the geysers. The pressure records do not indicate surge pressures sufficient to lift the water to the ground surface. Features of the pressure records can be interpreted to indicate the release of large air pockets through the manhole shaft similar to the laboratory experiments. These results suggest that the entrapment of large air pockets is an important component to the geysering process and that tunnel design procedures need to properly account for air effects.     

高炉鼓风机防喘振控制系统的改造

结合涟钢高炉1#鼓风机防喘振控制系统改造的具体实例,介绍了喘振的形成和危害,阐述了防喘振控制的原理及控制系统的实现方法.     

Experimental Investigation of Surges in a Stormwater Storage Tunnel

Below-grade storage tunnels in stormwater systems are usually designed to operate in a free-surface flow regime. However, intense rain events may trigger flow regime transition to pressurized flow, which results in operational problems. To date, little guidance is available as to the considerations necessary to properly design a system undergoing flow regime transition. In this investigation, an experimental apparatus consisting of a 14.6-m-long, 94-mm-diameter acrylic pipe was used to observe the nature of flows in such conditions. It was noticed that the air near the pipe crown may pressurize and influence the flow dynamics. Qualitative observations regarding the interactions between the air and water phases during the filling events are included in this study. Generally the surge intensity was maximized when a hydraulic bore propagating towards the surge riser just filled the pipe cross section, and it increased with the pressure head behind the pressurization front. Furthermore, the results indicate that the effects of air phase pressurization should be properly included in numerical simulations if ventilation conditions are limited.     

激波稳定风量的新型高炉风口理论与实验研究

通过气体力学理论的研究与分析,设计了一种新型的高炉风口;实验结果表明,该风口能利用激波自动调节并抵制炉内压力的波动,实现稳定供风,稳定高炉的操作。该种高炉风口将成为炼铁行业高炉风口更新换代的新设备。     

空气压缩机防喘振系统测试

空气压缩机工作点表现在性能曲线上,当工作点进入喘振区时,对压缩机危害极大。为了有效保护压缩机,避免进入喘振区,设置防喘振保护系统。随着运行时间的增长,压缩机的性能曲线变化较大时,有必要对其防喘振保护系统进行测试和修订。     

防喘振调节系统在鼓风机生产中的应用及技术改进

介绍了防喘振阀的控制原理及其在鼓风机工艺中的重要作用,针对运行中存在的问题采取了相应的措施,取得了很好的效果。     

Pitfalls and sources of error in staging rectal cancer with endorectal us

Endorectal ultrasound (US) is an accurate technique for local staging of rectal cancer. Because the choice of surgery depends on the level of tumor invasion and lymph node involvement, the surgeon relies largely on endorectal US findings when planning treatment. However, staging inaccuracies can occur due to over or underestimation of tumor depth, misinterpretation of lymph node involvement, and operator inexperience. Technical pitfalls in US of the rectal wall include proximity of the lesion to the anal verge, improper balloon inflation, a nonperpendicular imaging plane, shadowing artifacts due to air or stool, reverberation artifacts, refraction artifacts, and a transducer gain setting that is too high. Sources of error in tumor staging with endorectal US include interpretation differences, endosonologist bias, tumor location, tumor stenosis, peritumoral inflammation, postbiopsy and postsurgical changes, post irradiation changes, hemorrhage, and pedunculated or villous tumors. Node size and appearance are not reliable indicators of lymph node involvement. Awareness of these sources of error will improve the technical quality of endorectal US studies and allow more accurate tumor staging.     

Z2000-2.9高炉风机喘振的预防

介绍了高炉风机的喘振现象及其危害,详细分析了气体流量的变化引起动叶前后气流速度三角形的改变,使气流偏离了设计的最佳冲角,造成气体脱离,为喘振提供了条件,并从运行维护的角度提出了防止喘振的几条措施。