滚子素线对数曲线及凸度1 滚子素线对数曲线 根据ZYS主编的EC型圆柱滚子设计文件,滚子对数曲线采用如下方程:Y = 2·(1-V2)π·E·WLwe·ln11-(2xLwe)2 mm 其中:V ---------- 材料泊松比,轴承钢取V = 0.3 E ---------- 材料弹性模量,轴承钢取E = 2.1168×105 N/mm2 Lwe ------ 滚子有效长度(mm),取49.2 mm W --------- 承受最大力滚子的最大载荷(kN) W = 5Pr/Z = 5×0.3Cr/Z = 5×0.3×604×103/14 = 64286 N则 Y = 2·(1-V2)π·E·WLwe·ln11-(2xLwe)2 = 2·(1-0.32)3.14×2.1168×105·6428649.2·ln11-(2x49.2)2 =3.58×10-3×ln11-(2x49.2)2按右图所示,滚子素线对应坐标值应为:X1 = 1, y1 = 0.0059 μmX2 = 5, y12 = 0.15 μmX3 = 10,y3 = 0.65 μmX4 = 15,y4 = 1.66 μmX5 = 20,y5 = 3.87 μmX6 = 24,y36 = 10.85 μmX7 = 24.5,y7 = 17.23 μm2 滚子曲线最大凸度 滚子曲线最大凸度按下式计算:δmax = K0·WLwe(1.1932 + lnLwe2a) mm其中:K0= 2.81×10-6mm2/N R = Dpw/〔(Dpw – Dwe)·Dwe〕= 190/〔(190 – 32)×32〕= 0.0376 a = 2(K0W/R·Lwe)1/2 = 2(2.81×10-6×64286/0.0376×49.2)1/2=0.625 则δmax = 2.81×10-6×6428649.2(1.1932 + ln49.22×0.625)= 0.01787 mm 取δmax = 0.017±0.003 mm3 滚子与挡边接触点接触角α及球基面R3.1 滚子与挡边接触点高度H1: 由于 内圈:H2 =(d2-d1)/4 =(171-158)/4 = 3.25 外圈:H3 =(D1--D2)/4 =(222-205.6)/4 = 4.1 H2
R与α最大时,H1min = 32/2 – Rmax×sinαmax = 16-2580×sin19′=1.74>1.5(油沟最大尺寸) R与α最小时,H1max = 32/2 – Rmin×sinαmin = 16-2480×sin15′=5.18<5.8(挡边最小有效高) 3.5 滚子球基面凸出量 根据左上图h = r - 124r2-c2其中:r = R= 2580 -100 = 2480~2580 Cb = 18.5-0.5 0 = 18.0~18.5 Cc = 25.5Cd = 32球端面至测量点(3.25mm处)落差为hbc =hac-habhac =(2480~2580)– 124(2480~2580)2-25.52 = 0.0328~0.0315hab =(2480~2580)– 124(2480~2580)2-(18~18.5)2 = 0.0163~0.0157 0.0173~0.0166则hbc =hac-hab =(0.0328~0.0315)–(0.0163~0.0157) 取0.015~0.016 (0.0173~0.0166) = 0.0165~0.0158 0.0155~0.0149全凸度had:had =(2480~2580)– 124(2480~2580)2-322 = 0.052~0.050计算结果: 球基面测点处落差:hac = 0.032~0.033 hbc = 0.015~0.016 球基面全凸度:had = 0.050~0.0524 滚子接触点处内外圈滚道宽度由右图知 h = 3.25tgαh0 = 3.25tgα0 =3.25tg17′ = 0.0161h1 = 3.25tgα1 = 3.25tg15 ′= 0.0142h2 = 3.25tgα1 = 3.25tg19′ = 0.0180外圈滚道宽:E′= E + 2h0 = 52.032+0.04+0.10。