本文關(guān)鍵詞： 高溫法蘭 螺栓力測(cè)量 金屬封裝RFBG　出處：《華東理工大學(xué)》2017年碩士論文　論文類(lèi)型：學(xué)位論文

【摘要】：合適的螺栓預(yù)緊力對(duì)保證高溫法蘭接頭的安全性能是非常重要的。眾所周知,高溫工況下由于法蘭接頭各部件熱胖脹系數(shù)不同、墊片應(yīng)力下降以及材料的高溫蠕變等會(huì)導(dǎo)致螺栓力發(fā)生明顯的變化,螺栓預(yù)緊力變化經(jīng)常會(huì)引起法蘭接頭的泄漏。由于高溫條件下影響法蘭密封性能的因素很多,很難通過(guò)傳統(tǒng)的設(shè)計(jì)來(lái)保證法蘭接頭的安全。因此為了更有效的判斷實(shí)際運(yùn)行中高溫法蘭接頭的安全性能,準(zhǔn)確測(cè)量高溫法蘭螺栓預(yù)緊力變化非常有必要。本文研究并制備出耐高溫金屬封裝可再生光纖布拉格光柵(metal-packaged regenerated fiber Bragg grating,MPRFBG)傳感器。基于該耐高溫應(yīng)變測(cè)量傳感器,提出高溫法蘭螺栓力測(cè)量方法。本文主要研究?jī)?nèi)容及結(jié)論如下:(1)通過(guò)磁控濺射和電鍍工藝制備出針對(duì)高溫法蘭螺栓力測(cè)量的一種新型耐高溫MPRFBG傳感器。光纖表面和Ti層之間以及Ni層和金屬基體之間具有較好的界面結(jié)合強(qiáng)度。采用點(diǎn)焊的方式將MPRFBG傳感器固定于螺栓光桿的表面,可實(shí)現(xiàn)高溫法蘭連接螺栓力的測(cè)量,為了方便起見(jiàn),本文中將這種點(diǎn)焊安裝有MPRFBG傳感器的螺栓稱(chēng)為"MPRFBG-螺栓"。該傳感器金屬封裝基體的結(jié)構(gòu)形式可以最大程度地減少傳感器安裝對(duì)被測(cè)螺栓本身性能的影響。(2)基于FBG傳感器的測(cè)量原理,提出一種便于工程應(yīng)用的高溫法蘭螺栓力測(cè)量方法,該方法可以克服MPRFBG傳感器對(duì)溫度和應(yīng)變交叉敏感的問(wèn)題。通過(guò)500℃以?xún)?nèi)不同溫度下的單軸拉伸試驗(yàn)和熱響應(yīng)試驗(yàn)獲得MPRFBG-螺栓對(duì)螺栓軸向力和溫度的響應(yīng)特性。MPRFBG-螺栓在室溫到500℃溫度范圍內(nèi)的恒溫條件下,Bragg波長(zhǎng)對(duì)螺栓軸向力表現(xiàn)出良好的線(xiàn)性、穩(wěn)定性和重復(fù)性。MPRFBG-螺栓在500℃以下的溫度范圍內(nèi)表現(xiàn)出良好的溫度傳感特性,采用三次多項(xiàng)式函數(shù)可以準(zhǔn)確擬合Bragg波長(zhǎng)與溫度之間的關(guān)系。(3)設(shè)計(jì)一個(gè)簡(jiǎn)單的高溫緊固件螺栓力測(cè)量裝置,并在400℃以下進(jìn)行了試驗(yàn),試驗(yàn)結(jié)果表明MPRFBG-螺栓可以被用于溫度高達(dá)400℃條件下的螺栓力測(cè)量。對(duì)比MPRFBG-螺栓測(cè)量結(jié)果和有限元模擬結(jié)果。結(jié)果表明,螺栓力的有限元模擬結(jié)果與MPRFBG-螺栓測(cè)量結(jié)果具有較好的一致性。這項(xiàng)測(cè)量技術(shù)可為高溫工況下螺栓緊固件的結(jié)構(gòu)健康監(jiān)測(cè)提供一種新的可能。
[Abstract]:Proper bolt pretightening force is very important to ensure the safety performance of high temperature flange joints. As we all know, under high temperature conditions, due to the different thermal expansion coefficient of each component of flange joint, The decrease of gasket stress and the creep of material at high temperature will lead to obvious change of bolt force, and the change of bolt preload force will often cause leakage of flange joint. There are many factors that affect the sealing performance of flange under high temperature. It is difficult to ensure the safety of flange joints by traditional design. Therefore, in order to judge more effectively the safety performance of high-temperature flange joints in actual operation, It is necessary to accurately measure the change of pretightening force of high temperature flange bolts. In this paper, the metal-packaged regenerated fiber Bragg gratings MPRFBG sensor for high temperature metal packaging has been studied and fabricated. The main contents and conclusions of this paper are as follows: 1) A new high temperature MPRFBG sensor for bolt force measurement of high temperature flange has been fabricated by magnetron sputtering and electroplating. The MPRFBG sensor is fastened to the surface of the bolt rod by spot welding. Can realize the high temperature flange connection bolt force measurement, for convenience, In this paper, the spot welding bolt with MPRFBG sensor is called "MPRFBG- bolt". The structural form of the metal packaging matrix of the sensor can minimize the effect of sensor installation on the performance of the bolt under test. The measuring principle of the inductor, A high temperature flange bolt force measurement method is presented, which is convenient for engineering application. This method can overcome the problem that MPRFBG sensor is cross-sensitive to temperature and strain. Through uniaxial tensile test and thermal response test at different temperatures within 500 鈩，

本文編號(hào)：1531070