貫流式水輪機課件

1、CHAPTER 9Bulb TurbinesIntroduction 9.1 General arrangement9.2 Main components9.3 Condition control 9.4 Monitoring instruments 9.5 Assembly and dismantlingIntroductionThe Bulb turbine is a reaction turbine which is used for the lowest heads. It is characterized by having the essential turbine compone

2、nts as well as the generator inside a bulb, from which the name is developed. A main difference from the Kaplan turbine is moreover that the water flows with a mixed axial-radial direction into the guide vane cascade and not through a scroll casing. The guide vane spindles are inclined in relation t

3、o the turbine shaft. Contrary to other turbine types this results in a conical guide vane cascade.The Bulb turbine runner is of the same design as for the Kaplan turbine, and it may also have different numbers of blades depending on the head and water flow.Introduction貫流式電站優(yōu)點：貫流式電站優(yōu)點：(1)(1)電站從進水到出水方

4、向基本上是軸向貫通。電站從進水到出水方向基本上是軸向貫通。 (2)(2)貫流式水輪機具有較高的過流能力和大的比轉(zhuǎn)速。貫流式水輪機具有較高的過流能力和大的比轉(zhuǎn)速。(3)(3)貫流式水電站的機組結(jié)構(gòu)緊湊，與同一規(guī)格的轉(zhuǎn)槳式機組相貫流式水電站的機組結(jié)構(gòu)緊湊，與同一規(guī)格的轉(zhuǎn)槳式機組相比其尺寸較小，可布置在壩體內(nèi)，取消了復雜的引水系統(tǒng)比其尺寸較小，可布置在壩體內(nèi)，取消了復雜的引水系統(tǒng)(4)(4)貫流式水輪機適合作可逆式水泵水輪機運行，進出水流道沒貫流式水輪機適合作可逆式水泵水輪機運行，進出水流道沒有急轉(zhuǎn)彎，使水泵工況和水輪機工況均能獲得較好的水力性能。有急轉(zhuǎn)彎，使水泵工況和水輪機工況均能獲得較好的水力性

5、能。 (5)(5)貫流式水電站一般比立軸的軸流式水電站建設周期短，投資貫流式水電站一般比立軸的軸流式水電站建設周期短，投資小，收效快，淹沒移民少，電站靠近城鎮(zhèn)，有利于發(fā)揮地區(qū)興建電小，收效快，淹沒移民少，電站靠近城鎮(zhèn)，有利于發(fā)揮地區(qū)興建電站的積極性。站的積極性。9.1 General arrangementA general arrangement of a Bulb turbine plant is shown in Fig. General arrangementFig. 9.2 shows the turbine in more detail.9.2 Main compo

6、nentsThe Bulb turbine consists of the following main components:- stay cone (座環(huán)座環(huán))- runner chamber (轉(zhuǎn)輪室轉(zhuǎn)輪室)- draft tube cone (尾水管錐形管尾水管錐形管)- generator hatch (發(fā)電機艙門發(fā)電機艙門)- rotating parts (旋轉(zhuǎn)部件旋轉(zhuǎn)部件)- turbine bearing (水輪機軸承水輪機軸承)- shaft seal box (主軸密封盒主軸密封盒)- guide vane mechanism (導水機構(gòu)導水機構(gòu))9.2.1 Stay c

7、one座環(huán)由內(nèi)環(huán)、外環(huán)、外環(huán)里襯、上部豎井和下部豎井、上下導座環(huán)由內(nèi)環(huán)、外環(huán)、外環(huán)里襯、上部豎井和下部豎井、上下導流板等組成。流板等組成。 9.2.1 Stay cone整個座環(huán)被分成八個扇形塊，各塊之間用螺栓緊固。整個座環(huán)被分成八個扇形塊，各塊之間用螺栓緊固。9.2.1 Stay cone垂直面上的上支柱和下支柱較粗，并具有中空的內(nèi)腔。下支柱垂直面上的上支柱和下支柱較粗，并具有中空的內(nèi)腔。下支柱與支墩連接，兩者的內(nèi)腔相通，從而形成了燈泡體的水輪機部分經(jīng)與支墩連接，兩者的內(nèi)腔相通，從而形成了燈泡體的水輪機部分經(jīng)過該支柱的支墩內(nèi)腔而通向燈泡體頭部的通道。在這個支柱內(nèi)還設過該支柱的支墩內(nèi)腔而通向燈

8、泡體頭部的通道。在這個支柱內(nèi)還設有水管和油管。上支柱內(nèi)腔裝有水管和其他設備，該內(nèi)腔還是由電有水管和油管。上支柱內(nèi)腔裝有水管和其他設備，該內(nèi)腔還是由電站廠房進入機組燈泡體的通道。站廠房進入機組燈泡體的通道。9.2.2 Runner chamber1 1、結(jié)構(gòu)：結(jié)構(gòu)：轉(zhuǎn)輪室由三個環(huán)帶組成轉(zhuǎn)輪室由三個環(huán)帶組成1 1）與導水機構(gòu)相毗連的錐形環(huán)帶；）與導水機構(gòu)相毗連的錐形環(huán)帶；2 2）作為轉(zhuǎn)輪室的球形環(huán)帶；）作為轉(zhuǎn)輪室的球形環(huán)帶；3 3）與尾水管毗連的后部錐形環(huán)帶。）與尾水管毗連的后部錐形環(huán)帶。轉(zhuǎn)輪室分瓣結(jié)合面采用法蘭連接，并應有可靠的止漏措施?；燹D(zhuǎn)輪室分瓣結(jié)合面采用法蘭連接，并應有可靠的止漏措施。混凝

9、土僅澆灌到水輪機的水平分半面處，使水輪機室上部可拆卸，凝土僅澆灌到水輪機的水平分半面處，使水輪機室上部可拆卸，以供裝拆轉(zhuǎn)輪之用。以供裝拆轉(zhuǎn)輪之用。為了觀察轉(zhuǎn)輪和轉(zhuǎn)輪室，在后部錐形環(huán)帶上開有進人孔。為了觀察轉(zhuǎn)輪和轉(zhuǎn)輪室，在后部錐形環(huán)帶上開有進人孔。在中心線附近，轉(zhuǎn)輪室由不銹鋼制成，以抵制氣蝕侵蝕。在中心線附近，轉(zhuǎn)輪室由不銹鋼制成，以抵制氣蝕侵蝕。9.2.2 Runner chamber2 2、轉(zhuǎn)輪掃膛、轉(zhuǎn)輪掃膛1 1）原因）原因流道沖水后，由于浮力的影響，轉(zhuǎn)輪會上浮，而轉(zhuǎn)輪室會整流道沖水后，由于浮力的影響，轉(zhuǎn)輪會上浮，而轉(zhuǎn)輪室會整體下沉變形，這樣造成靜態(tài)下調(diào)整好各部間隙和受力發(fā)生變化，體下沉變形

10、，這樣造成靜態(tài)下調(diào)整好各部間隙和受力發(fā)生變化，加上機組運行后，槳葉在水力作用下會帶動整個轉(zhuǎn)動部分軸向加上機組運行后，槳葉在水力作用下會帶動整個轉(zhuǎn)動部分軸向“竄動竄動”，這樣，槳葉就容易與轉(zhuǎn)輪室發(fā)生掃膛。，這樣，槳葉就容易與轉(zhuǎn)輪室發(fā)生掃膛。2 2）危害）危害輕度得掃膛會加大機組振動和機組的運行噪音，過大的掃膛輕度得掃膛會加大機組振動和機組的運行噪音，過大的掃膛會使槳葉卡阻甚至損壞。會使槳葉卡阻甚至損壞。 9.2.3 Guide vane mechanism1 1、結(jié)構(gòu)、結(jié)構(gòu)燈泡貫流式機組的導水機構(gòu)由內(nèi)、外配水環(huán)、導葉、導葉軸燈泡貫流式機組的導水機構(gòu)由內(nèi)、外配水環(huán)、導葉、導葉軸承、導葉操作環(huán)、重錘

11、、連桿拐臂及保護、限位裝置等組成。承、導葉操作環(huán)、重錘、連桿拐臂及保護、限位裝置等組成。9.2.3 Guide vane mechanism左圖為外環(huán)結(jié)構(gòu)，右圖為導葉及導水機構(gòu)內(nèi)外環(huán)結(jié)構(gòu)。左圖為外環(huán)結(jié)構(gòu)，右圖為導葉及導水機構(gòu)內(nèi)外環(huán)結(jié)構(gòu)。9.2.3 Guide vane mechanism2 2、導葉、導葉導葉下軸頸依靠套在它上面的并用銷子固緊的轉(zhuǎn)臂通過連桿導葉下軸頸依靠套在它上面的并用銷子固緊的轉(zhuǎn)臂通過連桿與控制環(huán)連接。傳動導葉的傳動機構(gòu)安置在燈泡體的水輪機部分與控制環(huán)連接。傳動導葉的傳動機構(gòu)安置在燈泡體的水輪機部分內(nèi)。內(nèi)。9.2.4 Runner1 1、轉(zhuǎn)輪、轉(zhuǎn)輪燈泡貫流式機組轉(zhuǎn)輪與軸流轉(zhuǎn)槳

12、式水輪機轉(zhuǎn)輪相似，同樣分為燈泡貫流式機組轉(zhuǎn)輪與軸流轉(zhuǎn)槳式水輪機轉(zhuǎn)輪相似，同樣分為兩類：兩類：1 1）貫流定槳式（）貫流定槳式（GDGD）2 2）貫流轉(zhuǎn)槳式（）貫流轉(zhuǎn)槳式（GZGZ）9.2.4 Runner特點：特點：1 1）轉(zhuǎn)輪葉片數(shù)一般為奇數(shù)，沒有絕對對稱，這樣要求安裝精）轉(zhuǎn)輪葉片數(shù)一般為奇數(shù)，沒有絕對對稱，這樣要求安裝精度就高，而且不容易滿足轉(zhuǎn)動平衡和重心落在旋轉(zhuǎn)軸線上；度就高，而且不容易滿足轉(zhuǎn)動平衡和重心落在旋轉(zhuǎn)軸線上；2 2）轉(zhuǎn)輪體內(nèi)充滿油，轉(zhuǎn)動體外充滿水，而且槳葉角度可調(diào)，）轉(zhuǎn)輪體內(nèi)充滿油，轉(zhuǎn)動體外充滿水，而且槳葉角度可調(diào)，所以對密封要求十分高；所以對密封要求十分高；3 3）流道充滿

13、水后，轉(zhuǎn)輪體和槳葉會上浮，而轉(zhuǎn)輪室會下沉，）流道充滿水后，轉(zhuǎn)輪體和槳葉會上浮，而轉(zhuǎn)輪室會下沉，這樣如果安裝精度或水導軸承間隙調(diào)整不當，極易造成轉(zhuǎn)輪掃膛這樣如果安裝精度或水導軸承間隙調(diào)整不當，極易造成轉(zhuǎn)輪掃膛或槳葉卡阻現(xiàn)象，影響機組的正常運行。或槳葉卡阻現(xiàn)象，影響機組的正常運行。 9.2.4 Runner2 2、轉(zhuǎn)輪接力器、轉(zhuǎn)輪接力器1 1）位置）位置槳葉接力器布置在轉(zhuǎn)輪體內(nèi)，由受油器供油。槳葉接力器布置在轉(zhuǎn)輪體內(nèi)，由受油器供油。2 2）作用原理）作用原理接力器作為操作架，它通過耳柄、連桿和固定在葉片樞軸上的接力器作為操作架，它通過耳柄、連桿和固定在葉片樞軸上的轉(zhuǎn)臂傳遞作用在葉片上的驅(qū)動力矩。轉(zhuǎn)

14、臂傳遞作用在葉片上的驅(qū)動力矩。用承受軸向力的螺栓將轉(zhuǎn)輪體固定在主軸上，用壓入螺釘精加用承受軸向力的螺栓將轉(zhuǎn)輪體固定在主軸上，用壓入螺釘精加工孔內(nèi)的受剪套筒承受扭矩。工孔內(nèi)的受剪套筒承受扭矩。9.3 Condition controlThe general principles for condition control are the same as for the Francis turbines. Further considerations are therefore connected only to a few specific details.9.3.1 RunnerThe run

15、ner should be inspected both from above and below. Particular attention should be given to possible cavitation erosion and scratches on the blades as well as leaks around the blade flange against the hub.9.3 Condition control9.3.2 Runner chamberThe narrow gap between runner and the runner chamber sh

16、ould be checked if foreign objects may have passed the gap and made scratches in the chamber.9.3.3 Guide vane mechanismFor guide vane mechanism with individual vane servomotors on bulb turbines it should be checked that the vanes have an identical movement.9.3 Condition control9.3.4 Shaft seal boxFo

17、r Bulb turbines at standstill it should be checked that the water does not flow out of the box along the shaft into the turbine bearing.9.3.5 Generally for Bulb turbinesSpecial attention should be paid to changes in the sound when the unit is in operation.9.4 Monitoring instrumentsThe turbine is nor

18、mally equipped with the following instrumentation: A manometer connected to the upstream end of the generator bulb A vacuum meter connected to the runner chamber downstream of the runner A contact manometer for reading of the pressure in the shaft seal box water pressure pipe, which triggers alarm o

19、r alternatively stop signal at too low pressure A contact manometer giving alarm:Pressurized water in the shaft seal box upon start of the unit9.4 Monitoring instruments A contact thermometer for reading of oil temperature in the bearing housing. The thermometer has two adjustable contacts, one for alarm at high temperature and one for disconnection for the unit on further temperature rise A remote indication thermometer with two temperature sensors for reading of temperature in lower bearing pad A level