手拉行车计算书1.0t -.doc

Calculation for 3T Hand Girder Crane1.0T 手拉行车计算书 1 技术参数 手动葫芦 起升重量 1000 kg 起升高度 3.0m 起升速度 手动行走速度 手动 2 工字梁刚度和强度的计算 工字梁的参数 工字梁型号 I18b 工字梁材料 Q235-B b=94mm h=180mm d=6.5mm t=10.7mm r=4.3mm R=8.5mm L≤2500mm Ix=1660cm4 Wx=185 cm3 Q1 装载重量 1000kgf Go 手拉行车自重 45kgf 设计动态因素: 1.15 安全因素: 1.5 2.1 弯曲强度弯矩 Mmax=(1.15 Q1+ Go)L/4=(1.15×1000+45)×250/4= 74687.5kgf.cm弯曲应力 σ= Mmax/Wx= 74687.5/185=403.7kgf/ cm2＜[σ0]［σ0］= 2350/1.5(safe factor)=1650kgf/ cm2 ∴ 安全 2.2 工字梁的刚度校核 弹性横梁. f≤[f]=(1/700~1/1000)L 取 [f]=L/800=3.125mm f=( 1.15Q1+ Go)×L3/48×E×Ix=1195×2503/48×2.1×106×1660 ≈0.11 mm=1.1mm＜[f] 2.3 轴的强度校核 手动葫芦上的轴直径是 42mm，材料为 45# 2.3.1 支撑反力 R’a= R’b=(1.15Q0+G’ 0) ×L/2/L =(1.15×1000+15)×L/2/L =1165/2=582.5kgfCalculation for 3T Hand Girder Crane已知: L﹍﹍﹍﹍轴长 L=12.8cmQ0﹍﹍﹍﹍承载负荷 Q0=1000kgG’ 0﹍﹍﹍﹍手动葫芦自重 G’ 0=15kg 2.3.2 轴的弯矩 M’a=M’b=Ra×L/2 =582.5×12.8/2=3728kgf.cm 取 M=M’a=3728kgf.cm 2.3.3 弯曲应力 σ=M/W=3728/π2.53/32×2 =1202.6kgf.cm2 ［σ0］= 4000/1.5(safe factor)=2667kgf/ cm2σ< [σ0]=2667kg/cm2已知: 材料 45 号钢。

淬火和回火后. [σ0]=4000kg.cm2 所以安全 2.4 校核梁的局部弯曲强度校核梁的局部弯矩强度校核工字梁边缘处的局部弯曲强度 在轮子的集中力下校核工字梁边缘处的强度：我们计算支撑 4 轮负载的情况中跨部分 的弯曲应力包括梁整体的弯曲应力和在轮子接触下梁边缘处的弯曲应力, 所以我们取他们的 合力，校核强度 竖直方向载荷下梁的弯曲正应力 RA＇= (1000 +45)/4=261.3Kgl=1/2(2500-205)=1147.5mmMPacmkgWlRXVD8 .312/32418575.11423 .2610工字梁边缘处弯曲应力的计算工字梁局部边缘处弯曲应力计算要注意以下几点: 抗剪筋板根部的水平和垂直弯曲应力 (point1) and 轮子的支反力 (point 2), and 在轮子自由边缘处水平和垂直平面的弯曲应力 (point 3),计算相关应力公式如下:（point1 水平弯曲应力）2112tPKp x（point1 垂直弯曲应力）2212tPKp zCalculation for 3.0T Hand Girder Crane（point2 水平弯曲应力）2322tPKp x（point2 垂直弯曲应力）2422tPKp z（point3 垂直弯曲应力）2532tPKp z公式中：K1、K2、K3、K4、K5——wheel pressure acting position ratio，see figure4-3-7[2],i—the distance between wheel pressure acting point 0liand web reinforcement outer side, refer to drawing and calculation，known i=32.5㎜，a flange width，a=54㎜。

So6 . 0Known from figure：K1=0.53、K2=0.11、K3=0.295、K4=0.78、K5=0.62Pp——single roller max. wheel pressure，Pp=261.3kg=2560.8Nt——flange thickness，t=10.7mmRelevant data to above formula，knownMPax7 .237 .108 .2560253. 021MPaz9 . 47 .108 .2560211. 021MPax2 .137 .108 .25602295. 022MPaz9 .347 .108 .2560278. 022MPaz7 .277 .108 .2560262. 0231) reluctant stress Lower flange surface point1 resultant stress  MPazzxzzx9 .438 .319 . 47 .238 .319 . 47 .2322112 12 11Lower flange surface point2 resultant stress  MPazzxzzx2 .618 .319 .342 .138 .319 .342 .1322222 22 22Lower flange surface point3 resultant stresscbacdφCalculation for 3.0T Hand Girder Crane MPazz5 .598 .317 .2733Small bending stress from horizontal load, we neglect it. Material is Q235-B, whose yield strength，MPaS235 MPanS1575 . 1 235I-beam lower flange local bending stress is less than allowed stress. So it’s safe.3 Strength check of wheel contacting facing material 45 HB=240-280 Known from assembly drawing, there are 4 wheels supporting the load For the safety calculate only 3 wheels to check the strength of contacting Surface.Known: Q1=1000kgf G=45kgf Design dynamic factor: 1.15 Reaction of the support on the wheel P=1/3(1.15Q1+G)=398kgfPartial contacting stress when the steel wheel and I-steel are in line contact. δt=600*(2P/bD) 1/2 =600*(2×398/3×11. 4) 1/2 =2671kgf/cm2 In equation b Contacting length of the wheel and rack b=3cmD Diameter of wheel take D=11.4cm It’s Known from diagram that hardness of contacting surface of the wheel is HB=320 [δt]=6400~8000kgf/cm2∴ Qualified. 4 Strength check of wheel shaft Choose the length of the actuating arm 3.4cm. Stress check in dangerous section δ=M/W=398×3.4/0.1×2.5 2=877kgf/cm2＜[δ-1]Material #45 steel Quenched and tempered.[δ-1]= 4000/1.5(safe factor)=2667kg/cm2 So: it is safe. 。