雙鞍座支撐的內(nèi)壓容器的合理設(shè)計(jì)

1、 畢 業(yè) 設(shè) 計(jì) 英 漢 翻 譯 設(shè)計(jì)名稱: 畢業(yè)設(shè)計(jì)英漢翻譯 題 目: 雙鞍座支承的內(nèi)壓容器設(shè)計(jì) 學(xué)生姓名: 楊正豪 專 業(yè): 化工裝備技術(shù) 班 級(jí): 裝備1011 學(xué) 號(hào): 201013040131 指導(dǎo)老師: 李 群 松 指導(dǎo)時(shí)間: 二0一二年十二月 雙鞍座支撐的內(nèi)壓容器的合理設(shè)計(jì)摘要通過(guò)對(duì)臥式容器的受力分析,認(rèn)為臥式容器的合理設(shè)計(jì)應(yīng)著重考慮容器鞍座包角、寬度B和最佳位置A,以及加強(qiáng)圈的設(shè)置、容器的長(zhǎng)徑比LDi等關(guān)鍵詞臥式容器應(yīng)力支座 臥式容器的受力分析和強(qiáng)度設(shè)計(jì)都是以齊克(L.P.Zick)提出的理論為基礎(chǔ)的,該理論對(duì)鞍座處筒體的受力與變形分析得較為詳盡,其所采用的一些假設(shè)是以實(shí)際應(yīng)力

2、測(cè)定為基礎(chǔ)的,并對(duì)應(yīng)力計(jì)算式進(jìn)行了修正。此外,還按應(yīng)力性質(zhì)提出了各種應(yīng)力控制值,實(shí)際應(yīng)用也是可行的。臥式容器的設(shè)計(jì)方法已在GB150-89鋼制壓力容器中作了明確規(guī)定,采用鋼制壓力容器設(shè)計(jì)計(jì)算軟件在微機(jī)上計(jì)算十便。1受力分析在設(shè)計(jì)臥式容器時(shí),所需進(jìn)行的受力分析首先是其承受的荷載:操作壓力(內(nèi)壓或外壓)、容器本身質(zhì)量(包括筒體、封頭和附件質(zhì)量)、物料質(zhì)量(應(yīng)考慮水壓試驗(yàn)時(shí)水的質(zhì)量)等。下面討論雙鞍座式臥式容器的受力分析。設(shè)計(jì)時(shí)除按常規(guī)計(jì)算圓筒、封頭的強(qiáng)度外,還應(yīng)驗(yàn)算支座處的局部應(yīng)力。此局部應(yīng)力的計(jì)算取決于支座結(jié)構(gòu)形式。雖然從受力情況分析,支座越多容器的最大應(yīng)力就越小,但常常由于地基不均勻沉陷、基礎(chǔ)

3、水平度的誤差或筒體不直、不圓等原因,造成支座反力分布不均,從而使容器的局部應(yīng)力增大,因此一般采用雙鞍座。2最佳鞍座位置雙鞍座臥式容器的有關(guān)尺寸(鞍座包角、鞍座寬度B、腹板厚度b和計(jì)算高度H等)按齊克理論分析。鞍座寬度將影響筒體周向應(yīng)力,其大小應(yīng)使支座處筒體的周向應(yīng)力不超過(guò)許用值,一般取b8Rm。鞍座包角增大可使筒體應(yīng)力降低,但鞍座變得笨重,材料消耗增多,同時(shí)也增加了鞍座承受的水平推力。而過(guò)分減小包角,設(shè)備容易從支座上傾倒,故通常采用=120,必要時(shí)取=150,因此設(shè)計(jì)時(shí)盡可能選用標(biāo)準(zhǔn)鞍座。鞍座位置的正確與否對(duì)容器中各項(xiàng)應(yīng)力都有影響,尤其對(duì)筒體軸向和周向應(yīng)力的影響更大。鞍座位置不合理有可能導(dǎo)致跨

4、距中點(diǎn)處的周向應(yīng)力值大于許用應(yīng)力值,因而不得不增加筒體壁厚(或增設(shè)加強(qiáng)圈),造成不必要的浪費(fèi)。所以,支座形心至封頭切線的距離A直接影響筒體的軸向應(yīng)力,另一方面還影響抵抗彎矩有效截面積的變化。當(dāng)筒體被封頭加強(qiáng)(即ARm015)時(shí),鞍座平面處的筒體上部不能自由變形,因而筒體中整個(gè)截面都可抵抗彎矩。當(dāng)A015Rm或筒體無(wú)加強(qiáng)措施而剛性不足時(shí),在周向彎矩的作用下,鞍座處筒體上將產(chǎn)生“扁塌”現(xiàn)象,成為無(wú)效區(qū)不起承載作用,從而使筒體中其他部位各種應(yīng)力增大。當(dāng)容器設(shè)有加強(qiáng)圈時(shí),整個(gè)圓筒都能承受彎矩,對(duì)跨距中點(diǎn)的軸向應(yīng)力只考慮彎矩變化的影響。因此在設(shè)計(jì)中應(yīng)盡量選擇A015Rm,以利于封頭對(duì)筒體起加強(qiáng)作用,此時(shí)

5、剪應(yīng)力值不隨A值而變化。當(dāng)A015Rm時(shí),剪應(yīng)力值隨A增大而減小,其減小值與LDi有關(guān)。LDi愈小,則減小愈多。根據(jù)材料力學(xué)分析,當(dāng)跨中截面與支座截面彎矩相等時(shí),用料及應(yīng)力分布最為合理。由此原則,導(dǎo)出支座中心與封頭切線間的距離應(yīng)為A=01207L,如果大于此值,支座處的軸向彎曲應(yīng)力將顯著增加。由以上分析得出,確定臥式容器鞍座的最佳位置,首先必須滿足A012L,其次盡量使A015Rm。臥式容器的支座設(shè)計(jì)通常按JBT4712-92選用A型或B型并作強(qiáng)度校核,鞍式支座可根據(jù)工藝需要進(jìn)行調(diào)整。為防止容器熱膨脹以及載荷對(duì)筒體引起附加應(yīng)力,確定一個(gè)支座固定,另一個(gè)支座可活動(dòng),使設(shè)備能自由伸縮。3加強(qiáng)圈的設(shè)

6、置筒體內(nèi)設(shè)置加強(qiáng)圈可以加強(qiáng)鞍座處筒體,有效地降低周向應(yīng)力。對(duì)于壓力低、直徑大的容器,加強(qiáng)圈的設(shè)置是必不可少的。在設(shè)計(jì)過(guò)程中調(diào)整A值仍無(wú)法降低周向應(yīng)力時(shí),筒體必須設(shè)置加強(qiáng)圈。不論加強(qiáng)圈設(shè)在筒體內(nèi)側(cè)或外側(cè),其位置以在鞍座平面處最為合理。加強(qiáng)圈的設(shè)置還可增加筒體剛性,使其整個(gè)截面都承受剪力作用。4臥式容器長(zhǎng)度與直徑之比LDi容器的容積一般是根據(jù)工藝需要而給定的,但有時(shí)工藝上僅給定容器的長(zhǎng)度或直徑。設(shè)計(jì)時(shí)應(yīng)在滿足工藝要求的前提下盡可能做到用材少、結(jié)構(gòu)簡(jiǎn)單、制造方便,這就要求合理地調(diào)整筒體的長(zhǎng)徑比LDi。在使容器用材最少的前提下,對(duì)低壓容器應(yīng)先按壓力求得壁厚以取合理直徑Di。一般在容器容積V一定的條件。

7、結(jié)論(1)雙鞍座臥式容器的設(shè)計(jì)程序?yàn)?合理選擇容器長(zhǎng)徑比LDi;根據(jù)GB150-1998初定筒體的計(jì)算壁厚S;試定鞍座位置A,選定鞍座包角,計(jì)算各應(yīng)力值并確定是否在允許的范圍內(nèi);改變不符合要求的初選參數(shù)以調(diào)整各有關(guān)應(yīng)力值,使之完全符合要求。(2)要使臥式容器的設(shè)計(jì)更為合理,應(yīng)全面考慮容器最佳鞍座位置A、加強(qiáng)圈的設(shè)置、容器的長(zhǎng)徑比LDi。Double saddle support of the internal pressure vessel design reasonableTo pick through the horizontal vessel force analysis, it is

8、thought that the reasonable design of horizontal vessel shall be considered container saddle wrap Angle , width B and best position A, and reinforcing ring Settings, containers of length to diameter ratio L Di, etcKeywords horizontal vessel stress supportHorizontal vessel stress analysis and strengt

9、h design are zeke (L.P.Z ick) put forward on the basis of the theory, the theory of saddle in the barrel of the stress and deformation analysis are more detailed, the use of some of the hypothesis is the basis of the actual stress measurement, and the stress calculation formula was revised. In addit

10、ion, according to the stress properties puts forward all kinds of stress control values, practical application is feasible. Horizontal vessel design method has been gb1501998 steel pressure vessel made specific provision, use steel pressure vessel design calculation software based on calculation and

11、 ten.1 force analysis in the design of horizontal vessel, what are the force analysis is first the bear load: operating pressure (internal pressure or external pressure), container itself quality (including cylinder body, head and accessories quality), material quality (hydraulic test should be cons

12、idered when the quality of the water), etc. In the following discussion on double saddle type horizontal vessel force analysis. In addition to conventional design according to the calculation, the strength of the cylinder head outside, still should check support in the local stress. The local stress

13、 calculation depends on the support structure. Although the stress situation analysis, support more containers maximum stress is small, but often due to the inhomogeneous settlement of ground, foundation levelness error or barrel is not straight, round and other reasons, resulting in counteracting f

14、orce uneven distribution, so that the container of local stress increase, so generally adopts double saddle.2 the best saddle position double saddle horizontal vessel about size (saddle wrap Angle , saddle width B and web thickness B and calculation height H, etc.) according to zeke theoretical anal

15、ysis. Saddle width will affect barrel circumferential stress, its size should make support in the barrel of the circumferential stress not more than allowable value, generally take b or eight rm. Saddle wrap Angle increase can make the barrel stress is reduced, but the saddle become bulky, and mater

16、ials consumption increased, at the same time also increases the saddle withstand level thrust. And too much reduced Angle, the equipment is easy to fall from the bearing, so usually adopt = 120 , when necessary, take = 150 , so when the design as far as possible choose standard saddle. Saddle positi

17、on is correct or not to container in the stress have influence, especially for cylinder axial and circumferential stress more influence. Saddle position is not reasonable can lead to span in the middle of circumferential stress value is greater than the allowable stress value, thus to increase the c

18、ylinder body wall thickness (or additional stiffening ring), resulting in unnecessary waste. So, support centroid to head tangent distance A directly influence the barrel of the axial stress, on the other hand also affected the resistance moment effective cross-sectional area change. When the cylind

19、er is head strengthen (i.e. A Rm acuities 015), saddle plane in barrel upper not free deformation, and barrel in the cross section can resist bending moment. When A 015 rm or barrel without strengthening measures and rigid is insufficient, in the circumferential bending moment, under the action of s

20、addle place barrel will produce saddle phenomenon, become invalid area not load effect, so that the barrel in other parts of the various stress increases. When the container with reinforcing ring, the whole cylinder can withstand bending moment, the mid span of the axial stress only consider the imp

21、act of the changes that moment. So in the design should try to choose A acuities 015 rm, in order to head for barrel on strengthening effect, the shear stress values are not with A value and change. When A 015 rm, shear stress value and decreases with A, the reduced value and L Di relevant. L Di is

22、small, then the more reduced. According to the material mechanics analysis, when the middle section of the middle span and support section bending moment is equal to, with makings and stress distribution of the most reasonable. This principle, derived support center and head tangent distance between

23、 should be A = 01207 l, if greater than this value, bearing in axial bending stress will be increased significantly. By the above analysis, determine the horizontal vessel saddle in the best position, first must satisfy A acuities 012 l, then try to make A acuities 015 rm. The sun cat, good afternoo

24、n ; T4712-92 choose type A or B type and intensity of the saddle support according to need to carry on the adjustment process. In order to prevent container and thermal load on barrel cause additional stress, determine a support fixed, another support can activity, make the equipment can free expans

25、ion.3 reinforcing ring Settings the cylinder body set stiffening ring can strengthen saddle place barrel, effectively reduce the circumferential stress. For low pressure, diameter of vessel, reinforcing ring Settings is indispensable. In the design process for the adjustment of A value still cannot

26、reduce the circumferential stress, barrel must set stiffening ring. Regardless of reinforcing ring in the cylinder body side or lateral, its position in saddle plane place the most reasonable. Reinforcing ring Settings can also increase the barrel rigid, make its whole section are under shear action

27、.4 horizontal vessel length to diameter ratio of L Di container volume is generally according to technology needs and given, but sometimes only process given container length or diameter. When the design should meet the technological requirements in the premise of less as far as possible do material, simple structure, easy fabrication, which requires the reasonable adjustment of the barrel length to diameter ratio L Di. In the c