下载此文档

挤压机挤压筒过盈计算.doc


文档分类:汽车/机械/制造 | 页数:约62页 举报非法文档有奖
1/62
下载提示
  • 1.该资料是网友上传的,本站提供全文预览,预览什么样,下载就什么样。
  • 2.下载该文档所得收入归上传者、原创者。
  • 3.下载的文档,不会出现我们的网址水印。
1/62 下载此文档
文档列表 文档介绍
该【挤压机挤压筒过盈计算 】是由【帅气的小哥哥】上传分享,文档一共【62】页,该文档可以免费在线阅读,需要了解更多关于【挤压机挤压筒过盈计算 】的内容,可以使用淘豆网的站内搜索功能,选择自己适合的文档,以下文字是截取该文章内的部分文字,如需要获得完整电子版,请下载此文档到您的设备,方便您编辑和打印。Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
挤压筒过盈配合计算
StudyontheInterferenceFitofExtrusionContainer
中国重型机械研究院
重庆大学
ChinaNationalHeavyMachineryResearchInstituteCo.,Ltd.
ChongqingUniversity
,2023
目录
4
4
4
5
8
9
10
12
、解析解及有限元结果比照 17
20
21
: 21
: 27
32
: 32
: 37
42
: 42
: 47
52
: 52
: 57
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
主要工作
;
、解析解与有限元计算比照;

Thisreportincludes:
Theanalyticsolutionsonthestressesofextrusioncontainer.
Acomparisonbetweentheempirical,analyticsolutionsandFiniteElementAnalysis(FEA)results.
FEAontheinterferencefitoftheextrusioncontainerof120MNExtrusionPress.
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,

挤压筒在挤压过程中受三向应力,分别为径向压力,周向压力和轴向压力,挤压沿轴向应力分布比拟均匀,所以将挤压筒可简化为厚壁圆筒模型,即为平面应变问题,根据弹性力学计算三层圆挤压筒的接触应力及受内压时的应力应变。


等厚较长的圆筒,内外外表受有径向均匀分布的压力作用,并假定压力沿筒轴方向均相同。由于压力和物体本身的对称性,故变形后的圆筒对其轴线一定也是对称的,所以当利用极坐标时既没有切向位移也没有剪应力,这是轴对称的弹性力学平面应变问题。

()

()
圆筒开口时不受轴向力,此时,
()
整理计算得到
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
()

()

()
经计算得到最终解为:
()
()
其中积分常数、可由边界条件决定。

〔一〕圆筒受有均匀内压
设内压力为,时,边界条件变为:
当时,;当时,。
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,


,那么应力应变关系变化为:
()
()
()
并且在处,圆筒内圈位移变化为:
()
〔二〕圆筒受有均匀外压力
设外压力为,边界条件为当时,;当时,。。
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,


,可得应力应变关系式为:
()
()
()
外径变化为
()
〔三〕圆筒受均匀分布的内外压
设内压力为,外压力为,此时边界条件为当时,;当时,。,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,


利用此边界条件可得应力应变公式为:
()
()
()

单层挤压筒工作时内壁存在很高的峰值,而采用组合挤压筒可以利用装配产生的压应力来抵消由于挤压力而引起的拉应力,采用预应力组合的挤压筒,允许采用比单层挤压筒高的工作压力。
挤压筒一般采用三层或四层组合结构来提高挤压筒的承载能力,使用组合筒代替单层筒,可以提高使用寿命,改善受力情况。组合筒各层之间采用过盈装配,由内向外进行热装,各层之间会产生预紧力的组合,内层的压应力大于外层的压应力,过盈面处的压应力最大,有效的提高了挤压筒的刚度。当内外表受压时,整个筒子收到向外的拉应力,与预紧产生的压应力抵消一局部,余下的拉应力处于组合挤压筒屈服强度范围内,使挤压筒内应力趋于均匀,有效地提高挤压筒的受载能力,所以研究挤压筒的接触应力非常有必有,下面是对三层挤压筒的接触应力计算,并与经验公式做出比照,提出了经验公式中的缺乏之处。
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,

在不受内压的情况下,三层挤压筒分开单算两层筒子时,接触应力只受过盈量的影响,即两层组合筒之间的接触应力。
设组合筒的内外圆筒在装配前内筒的外半径较外筒的内半径大,装配后接合处的公共半径为。
设外筒受装配内压力的作用而内半径增大,内筒因受装配外压力的作用而外半径缩小,那么可得
()
,由于可得
()
,由于可得
()

()
那么在计算三层组合挤压筒时,,可以先计算第一层和第二层之间的装配应力,第二层和第三层之间的装配应力,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,

再将第一层和第二层视为一体,受到压应力的作用,
将第二层和第三层视为一体,受到压应力的作用,
所以三层挤压筒在接触面上的径向压应力为装配应力与压应力的叠加
三层挤压筒在接触面位置时的切向应力值为

在装配时,内层、中层和外套要用压力使之成为一体。装配应力的大小可以用公差控制。缪勒提出挤压筒外套的外径为内衬内径的4~5倍左右的理论。内衬的壁厚不应超过它所必须克服的工作用力的需要,但是这一点并不会在所有情况下满足,那么在实际经验的根底上,近似地确定挤压筒内衬的壁厚。
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,
Countycontinuationrecordshasexaminedandapprovedthedraft,spirit,believe,comprehensiveYearbookofzhuanglangalreadyprepareddraft,

挤压机挤压筒过盈计算 来自淘豆网m.daumloan.com转载请标明出处.

非法内容举报中心
文档信息