大型汽轮机进汽插管密封型式

大型汽轮机进汽插管的关键技术主要体现在密封型式方面,密封型式有3种,从密封效果、可靠性及工艺性等方面进行比较,认为叠片式密封的优势比较大,应用前景广阔。     

瓦斯抽放钻孔封孔工艺优化探讨

A煤矿原来采用的封孔处理工艺存在很多问题,无法准确地对注入的水泥浆量进行控制,也不能对封孔剂进行定位,解决不了在不同倾斜角度下的封孔漏气问题,需要对原封孔工艺进行优化。从现场实际应用效果来看,新封孔处理工艺可以有效提升封孔处理效果。     

油田管线施工双侧带压封堵技术的应用

新时期,在油田的管线施工过程中,因管线中多为一些易燃易爆的介质,为了保证油田管线施工的安全,应采用双侧带压封堵技术,基于此,对双侧带压封堵技术在油田管线施工中的应用进行了研究,进行了双侧带压封堵技术在当前油田管线施工中运用的调查,并在此基础上提出了油田管线施工中双侧带压封堵技术的工艺和施工应用。     

利用长喉部射水抽气器排水余能带抽轴封冷却器的设计研究

分析了长喉部射水抽气器和轴封系统的工作特性,首次在双抽汽凝汽式35MW汽轮机中成功应用长喉部射水抽气器的排水余能带抽轴封冷却器,使汽轮机的轴封系统简化、经济、安全可靠。     

Material behavior of rubber sealing for proton exchange membrane fuel cells

Reliable sealing is necessary for the stable operation of proton exchange membrane fuel cell (PEMFC). In practical application, various materials have been tried in PEMFC sealing. However, the mechanical properties of these sealing materials, which play a key role in the sealing stability, have not been fully understood in PEMFC environment, especially after long-term operation. In this paper, according to the operating environment of PEMFC, sealing material experiments are carried out to explore the differences in mechanical behaviors of sealing materials, including silicone rubber (SR), fluororubber (FR), nitrile rubber (NBR) and ethylene-propylene-diene-terpolymer rubber (EPDM) and the variation of mechanical properties of these sealing materials is predicted as time goes on. The results indicate that compression rate has a great influence on sealing contact stress. SR and EPDM, with the variation of 0.15 MPa and 0.45 MPa in stress, show the best and worst mechanical stability at different compression rates, respectively. In terms of temperature, it is found that SR can adapt to different operating temperature of PEMFC and only 18% variation is found from 20 °C to 100 °C. Finally, based on Time-Temperature Superposition (TTS), high temperature experiments are conducted to predict long-term relaxation stress under PEMFC working condition. The analysis results are beneficial for choosing suitable sealing material, and it can also be applied to predict sealing ability in PEMFC.     

柴油机缸体冷却水腔密封面穴蚀修复工艺

针对柴油机缸体冷却水腔密封面穴蚀影响水腔密封性,导致机油乳化、冲缸等问题,制定了特定的修复工艺。采用镶嵌不锈钢套的方法消除穴蚀,并将缸体加工至原形位尺寸,恢复了缸体的使用性能。实际应用证明了该工艺的可靠性。     

火电厂管道阀门带压堵漏技术应用分析

带压堵漏技术是指在不影响生产正常进行的前提下,带温、带压修复泄漏部位,达到重新密封的一种特殊技术手段。本文介绍带压堵漏原理,夹具制作过程,以及在电厂中的应用。