Research And Solve Of A Low Speed Radial Truck Cab Cracking

The Low Speed Radial Truck designed and manufactured by machinery Co. Ltd ofQinZhou is popular among the farmers for its excellent power and big cargo capacity.Since the low-speed heavy-duty trucks are mainly used in short-distance transportbetween urban and rural areas, the trucks are mostly working on the road of rural dirt,mountain jungle, sand and so on. Because of the hostile road conditions, some kinds ofrupture in certain parts of the cab on the low-speed heavy-duty truck will appear afterusing for a period of time, which results in great security risks for users. It is an urgentproblem for the company to solve the problem of cab fracture and improve the marketcompetitiveness. The research issue is based on this kind of problems.For this kind of problems, this paper presents an in-depth study on reasons whichmay lead to the fracture of the cab, and gives an promotion approach to the issue forsatisfying the requirement according to the results of the analysis.Firstly, achieve thepoint cloud by coordinate measuring machine, together with three-dimensional pointcloud processing software to build a three-dimensional model of the cab for subsequentanalysis.Secondly, create finite element model of the cab with the method of scientificanalysis of structure. According to the actual measurement of displacement from theground of the two girders on the experimental low-speed truck under the condition of thebending and twisting, the volume of displacement of the6suspensions can bedetermined. With the result of displacement regarded as the boundary condition, a staticanalysis of the cab is carried out to get a stress nephogram on the bend torsion condition.The analysis of the stress nephogram shows that the cab eligible under the staticcondition, but the fenders are not. Meanwhile, the strain experiment of cab under staticcondition matches the finite element analysis, which verifies the rationality of the finiteelement analysis.Thirdly, through the Adams software, the multi-body dynamics analysis of the cab iscarried out with the experimental collection data of excitation signal on the cab. Theresult of theoretical dynamic stress under the actual road conditions proves the validity ofthe multi-body dynamics model with the comparison with the experiment of dynamicstress result. At the same time, from the result it can be known that the double side pillarsof windshield frame on the cab are located in the area with a greater mount of stress, andstress concentration phenomenon exists.Fourthly, compound the excitation signals of the cab on all kinds of road conditionsinto the combined excitation spectrum, and give fatigue estimation with the spectrum toget the lifespan of the cab, which helps to provide the reference for retrofit.Finally, according to the former dynamic analysis, static analysis and fatigueanalysis, this paper gives a promotion method on the weak position. The result of fatiguelife estimation after improvement also verifies the advantage than the former one. In this research, the cab's3D mode is obtained through to the reversing. With theanalysis for static, dynamic characteristics analysis and fatigue analysis, the static anddynamic characteristics of the cab and the fatigue life can be achieved. The numericalmodel and the analysis can also provide a good technical support for the enterprise toretrofit the cab subsequently. At the same time, the improvement plan which is refinedform the data analysis shows the advantage than the former one, which helps solve theproblem of fracture for the enterprise.