主轴强度刚度等计算公式汇总及实例(精品文档)

1、一、选材某种型号电机40Cr HB284 322抗拉强度 b700MPb屈服点 500MPbb弯曲疲劳极限 -1 320MPb弯曲疲劳极限 -1 185MPb许用静应力 +280MPa许用疲劳应力 -1 =177213MPa二、轴的强度计算轴的结构设计和受力分析轴的结构尺寸参见 WYJ133-20-3受力分析：轴伸端上轴的最大载荷为 50KN 转子部分的磁极重约为 0.92KN轴伸处飞轮重约为 1.12KN额定转矩 ( 扭矩)TN=1100Nm=1.1106N外解得：圆柱滚子轴承支反力：FA=22.96KN调心滚子轴承支反力： Fc=75.0KN调心滚子轴承支承中点 C截面C 截面弯矩M=3.

2、99 106 NmmC轴伸端支承中点 E截面弯矩 , (E 至受力点距离)E 截面弯矩 ME=1.35 106 N2. 轴的 C截面强度校算(截面直径)抗弯断面系数33W=d/ 32=269.393抗扭断面系数3WP=d/ 16=538.78弯曲应力幅 a=MC/W=14.81MPa切应力幅 m= a=TN/(2WP)=1.02MPa对称循环弯曲应力的平均应力 m=0正应力有效应力集中系数 K=2.73切应力有效应力集中系数 K=1.96表面质量系数 =0.91尺寸系数 =0.6,=0.68平均应力折算系数 =0.21只考虑弯矩作用时的安全系数S=-1/ K /( )+ =4.32am只考虑扭

3、矩作用时的安全系数S= -1 / Ka/( )+ m=53.70C截面安全系数 S=SS/ S2+S2=4.31S=1.3 2.5 即C截面是足够安全的3. 轴的 E截面强度校算( 截面直径 ,键槽宽,高, )抗弯断面系数32/d=151.23W=d/32-bt(d-t)3抗扭断面系数32WP=d/16-bt(d-t)/d=320.9弯曲应力幅 a=M/W=8.931MPaE切应力幅 m= a=TN/(2WP)=1.71MPa 对称循环弯曲应力的平均应力 m=0 正应力有效应力集中系数 K=2.73 切应力有效应力集中系数 K=1.96320185280177ab92

4、1.121.122.9574.993.9926.51.35140269.39538.7814.801.0202.731.960.910.60.680.214.3253.664.31OK12022168.74338.398.531.6302.731.96表面质量系数 =0.91尺寸系数 =0.6,=0.7平均应力折算系数 =0.21只考虑弯矩作用时的安全系数S=-1/ K /( )+ =4.32 am只考虑扭矩作用时的安全系数S= -1/ Ka/( )+ m=53.70E截面安全系数 S=SS/ S2+S2=4.31S=1.3 2.5 即E截面是足够安全的三、轴的钢度计算扭转变形材料的切变模量

5、G=8.1 108MPa轴受转矩作用的长度和外直径： d1l1d2l2扭转角 : T 10+6 ,G 10+8,5842Ti li0.47106/ m0.25 / m 1 / mGdi4i 1挠度计算各轴段的直径和长度 :d1d2d3d4d56074120120152l1l2l3l4l515.519434323各轴段弯矩 :105NM0M1M2M3M403.567.9217.7928.06在B处加单位力不从 1N时引起轴上各段的弯矩 :NMMMMM0123408.4318.7742.1722.57在D处加单位力不从 1N时引起轴上各段的弯矩 :NMMM M M 000102030407.111

6、5.8335.5655.29材料的弹性模量 E=2.1 105MPa4截面的惯性矩4I= d/64, 单位轴中间转子支架支承点 B处挠度6yBli M i M idl0.0033mmy 0.034mm0EIii16liyBM1(2M)1M 2 )M2(2M2M 1i1 6EII处挠度0.910.60.70.217.5034.637.33OK8.114010112069.54.74E-07OKd6d7140140l6l726.551.5M5M633.6839.87MM5612.08M M 050665.84782M1+M22M2+M14.2M1+M25.2M2+M17.Ii*105i )10 5

7、8. (li /I9.M1(4.)(8.)10.M2(5.)(8.)11.=9.+10.12.= 1113.y= 11/6E结论处挠度8.4335.6479.71106.9057.2124.1616.8745.98103.1187.3046.7312.086.3614.72101.79101.79262.03188.572.44E-051.29E-054.22E-064.22E-068.78E-071.41E-060.00E+001.64E+022.67E+028.03E+021.41E+021.14E+021.46E+024.70E+027.75E+021.03E+031.38E+026.7

8、7E+011.46E+026.34E+021.04E+031.84E+032.79E+021.82E+024.12E+030.0032703750.034OK4.2M01+M025.2M02+M017.Ii*105i )10 58. (li /I9.M1(4.)(8.)10.M2(5.)(8.)11.=9.+10.12.= 1113.y= 11/6E结论7.1130.0567.22126.41176.42209.6814.2238.7786.95146.14186.97221.846.3614.72101.79101.79262.03188.572.44E-051.29E-054.22E-06

9、4.22E-068.78E-071.41E-060.00E+001.38E+022.25E+029.50E+024.34E+029.92E+021.23E+023.96E+026.53E+021.73E+035.53E+021.24E+031.23E+025.34E+028.78E+022.68E+039.87E+022.24E+031.01E+040.0080154660.034OK轴上调心滚子轴承支承中点 C截面的偏转角计算在C截面处加单位力矩 1N时引起轴上各段的弯矩:M11M12M13M10NM14M15M160.091176470.2029411760.4558823530.7088

10、240.844117616li MMyci1i dl0.0033mmy0.034mmc0C截面偏转角i 1EI i6liM1 (2M 11 M 12 )M2 (2M 12 )cycM11i 16EI I4. 2M0.090.390.861.622.262.6911+M125. 2M0.180.501.111.872.402.8412+M117.Ii*1056.3614.72101.79101.79262.03188.57i )10 58. (li /I2.44E-051.29E-054.22E-064.22E-068.78E-071.41E-069.M1(4.)(8.)0.00E+001.77

11、E+002.88E+001.22E+015.57E+001.27E+0110.M21.58E+005.08E+008.38E+002.22E+017.09E+001.59E+01(5.)(8.)11.=9.+10.1.58E+006.85E+001.13E+013.44E+011.27E+012.87E+0112.= 119.54E+0113. C=7.57078E-05rad0.0511/6E结论OK四、轴的临界转速（本电机转速低，可以不验算临界转速）五、键的强度计算假设压力在键的接触长度内均匀分布，则根据挤压强度或耐磨性的条件性计算，求得联接能传递的转矩静联接 键盘秘能伟递的力矩T= 1/2 hl d pMpaWYJ133WYJ103键规格22143218h67l 3948d120120 p8080T11232001612800TN11000002200000OKNO转子中点至左端面77.58d8120l826.5M7M