... ) ( ) 5 ,22 5 584.37.85,0 15,7.11,115 .2 5 ,23 7.5,0 121 10.05,1 2 3 26 1 = + − = tx t σ N/mm 2 ( ) ( ) 35,146 1460.37.85,0 525 ,7.11,115 .2 5 ,23 7.5,0 121 10.05,1 2 3 26 2 = + − = tx t σ N/mm 2 Ta tháúy ... m s = ( ) ( ) ⇒÷=÷=÷ 825 ,355 ,21 220 3,0 02, 003,0 02, 0 L Chn m s = 3mm ta cọ säú ràng bạnh dáøn : Z 1 = 30 15 ,23 122 .2 1 2 22 = + = + im L s . Suy ra : Z 2 = i.Z 1 = 2, 5.30 = 75 ràng Tênh lải ... (Z 1 + 2cos ϕ 1 ) = 3 (30 + 2. cos21 0 48 , ) = 96 mm D e2 = m s (Z 2 + 2cos ϕ 2 ) = 3 (75 + 2. cos68 0 22 , ) = 22 7 mm + Âỉåìng kênh vng làn trung bçnh: d tb1 = d 1 (1 - 0,5 2, 76 121 37...