Design and Analysis of Mini Dumper Ajay P V 1 Vishnu K M 4 Sreeraj J Menon 7 Daise T Mechery 2 Afsal Fajarudheen 5 Akhil Viswanath K C 8 Assistant Professor Gokul Krishnan T N 3 Delvin T D 6 Abstract A mini dumper is a machine, which is capable of loading and unloading of materials. We are trying to put forward a simple mini dumper design which is small in size, so it can be used in narrow passages. Simple mechanisms are employed for the mini dumper to ensure easy operation and maintenance. The chassis and storage bucket are analyzed with the help of ANSYS Workbench and conclusions have been made. Keywords mini dumper, static structural analysis, chassis, storage bucket I. INTRODUCTION A dumper is a vehicle designed for carrying bulk material, often on building sites. Dumpers are distinguished from dump trucks by configuration: a dumper is usually an open 4-wheeled vehicle with the load skip in front of the driver, while a dump truck has its cab in front of the load. A mini dumper with self-loading version allows a single operator to carry out the work of two or more persons in total autonomy. It carries load from one place to another. The self-loading shovel (loader) can transfer all sorts of material such as rubble, earth, aggregates etc. into the storage bucket quickly and safely with minimum operator effort. The mini dumper with hydrostatic transmission assures high performance and reliability and which could be equipped with a large number of accessories. Chassis and storage bucket are designed to carry heavy load without any major deflection. According to Abhishek Sharma [1], the box (hollow) section chassis help to reduce the weight of the chassis. He also states that box sections have less deformation and high strength than the C and I sections. II. DESIGN OF DRIVE SYSTEM For our mini dumper we uses a Honda GX 270 4- stroke petrol engine, because this engine can provide required torque for the hydrostatic transmission system. The specifications of engine were obtained and a model of the engine was made in solidworks 2016. The engine produces a power of 6.3 kw (8.4 hp) and a torque of 19.1 Nm at a speed of 2500 rpm. A. Design Of Belt Drive In order to transmit power from engine to hydraulic pump V-Belt drive system is used. The calculations were done following the books Machine Design and Design Data. Specifications are given in Table 1. The 3D model was created in Solidworks 2016 and rendered in Keyshot 6. Type of belt Diameter of smaller pulley Diameter of larger pulley Centre distance Table 1specifications of V-Belt Type B965 IS:2494 V-Belt 125 mm 158 mm 286.27 mm No. of belts 2 Centre to centre distance of groove Edge of pulley to first groove Width of pulley 19 mm 12.5 mm 44 mm 1741 www.ijaegt.com
Fig 1 V-Belt 2D Sketch Fig 4 Ball Bearing 3D Sketch Table 2: Specifications Of Ball Bearing Fig 2 V-Belt 3D Rendered Image B. Design Of wheel mount Bearing For the smooth rotation of wheels with respect to the wheel mount on the chassis and to carry load of materials as well as self weight, we require a bearing at each wheel mount. The calculations were done following the books Machine Design and design Data. The specifications are given in the table 2. The 3D model was created in solidworks 2011 and rendered in Keyshot 6. Type of bearing Inside diameter Outside diameter Width of bearing Ball diameter Dynamic capacity Maximum permissible speed III. DESIGN OF CHASSIS SKF7207B 35 mm 72 mm 15 mm 14.8 mm 2120 kgf 8000 rpm Shown below is the image of the mini dumper chassis that we designed. It acts as the back bone of our min dumper. It carries the load of materials as well as the self load of components. For our mini dumper, we used a hollow box cross section which has higher strength and less deformation than chassis with C and I cross sections. In order to find what happens to the chassis during fully loaded condition and also in unloading condition, we put the condition into static structural analysis in ANSYS Workbench 15. Fig 3 Ball Bearing 2D Sketch Fig 5 Chassis 2D Sketch 1742 www.ijaegt.com
Analysis was carried out on the chassis considering a load of 5000N and 2000N as the loads. The results of the analysis are shown in table 3. Table 3 Chassis - Analysis Results At normal condition At unloading condition The default mapped meshing with element size set to coarse were used here. The total number of nodes and elements generated here is 216387 and 115634 respectively. In normal condition, the loads of 5000N and 2000N are acted on the centre supporters and rear centre of the chassis respectively. Material : Structural steel Maximum deflection :0.1607 mm Maximum equivalent Von Mises stress : 101.79 MPa Minimum safety factor : 2.4561 Material : Structural steel Maximum deflection : 0.17143 mm Maximum equivalent Von Mises stress :109.57 MPa Stress Safety factor : 2.2815 Fig 8 Total Deformation at Normal Condition Fig 6 Mesh Fig 9 Equivalent Stress at Normal Condition Fig 7 Mesh (Enlarged View) Fig 10 Safety Factor at Normal Condition 1743 www.ijaegt.com
Fig 8 shows the total deformation of the chassis at normal position, it ranges from a minimum value of.0011526 mm to 0.1607 mm. Fig 9 shows the equivalent Von Mises stress which ranges from 0.00038952 MPa to 101.79 MPa. This value is less than the yield strength of structural steel which is 250 MPa. Fig 10 shows safety factor of 2.4561 at normal loaded condition. In unloading case, a load of 5000N acting on the front supporters and also at the hydraulic cylinder fixing point along with the load of 2000N produced by the engine and auxiliaries at the rear side of the chassis. Fig 13 Safety Factor at Unloading Fig 11 Total Deformation at Unloading IV. Fig 14 Chassis 3D Rendered Image DESIGN OF STORAGE BUCKET The following are the two storage bucket designs that we came up with. All the dimensions of both the frame designs are same, the only difference is the addition of ribs in the design 2. Fig 12 Equivalent Stress At Unloading Fig 11 shows the total deformation of the chassis at unloading, it ranges from a minimum value of.0020578 mm to 0.17143 mm. Fig 12 shows the equivalent Von Mises stress which ranges from 0.00028942 MPa to 109.57 MPa. This value is less than the yield strength of structural steel which is 250 MPa. Fig 13 shows the safety factor of 2.2815. Fig 15 Design 1 1744 www.ijaegt.com
Fig 16 Design 2 In order to find what difference the ribs made, we put both these into static structural analysis in ANSYS workbench 15.0. Analysis were carried out on both designs considering a load of 5000N acting vertical and a load of 2500N acting to the horizontal sides. The results of the analysis are shown in table 4. Table 4 Comparison Of Storage Bucket Designs Design 1 Design 2 Material : Structural steel Maximum deflection : 3.8029 mm Material : Structural steel Maximum deflection : 3.7626 mm Maximum equivalent stress : Maximum equivalent stress : 71.84 MPa 70.332 MPa Safety factor : 3.168 Safety factor : 3.5545 Fig 18 Mesh Enlarged View of Design 2 Fig 19 Total Deformation, Design 1 Fig 20 Equivalent Stress, Design 1 Fig 17 Mesh Enlarged View of Design 1 1745 www.ijaegt.com
Fig 21 Safety Factor, Design 1 Fig 22 total deformation, design 2 Fig 24 safety factor, design 2 Fig 19 shows the total deformation of the dumper with design 1. There is a maximum deformation value of 3.8029. Fig 20 shows the equivalent stress of the dumper with design 1. This value ranges from 3.3134*10-8 MPa to71.84 MPa. Fig 21 shows the safety factor for the dumper with design 1, which is about 3.168. Fig 22 shows the total deformation of the dumper with design 2. There is a maximum deformation value of 3.7626. Fig 23 shows the equivalent stress of the dumper with design 2. This value ranges from 1.6082*10-7 MPa to70.332mpa. Fig 24 shows the safety factor for the dumper with design 2, which is about 3.5545. The maximum and minimum values are shown by red and blue probes in each image. The result shows the addition of ribs gives more safer and better result than the design without ribs. So the design 2 is selected. Fig 25 storage bucket 3D rendered image Fig 23 Equivalent Stress, Design 2 1746 www.ijaegt.com
V. FINAL ASSEMBLY Some rendered images of final assembly are shown below, VI. CONCLUSION We successfully designed and analyzed the mini dumper by our self. The key factor of our design is simplicity. The storage bucket design ensures better strength and reliability which was proved using analysis results. Addition of ribs helps to improve the strength of storage bucket The chassis was found to be safe at fully loaded and unloading conditions. In all the cases the safety factor lies above 1. It shows the design is safe under limits. Fig 26 Isometric View Of Mini Dumper REFERENCES [1] Abhishek Sharma, Pramod Kumar, Abdul Jabbar, Mohammad Mamoon Khan, Structural Analysis of a Heavy Vehicle Chassis Made of Different Alloys by Different Cross Sections International Journal of Engineering Research & Technology (IJERT),ISSN: 2278-0181, Vol. 3 Issue 6, June 2014. [2] R.S Khurmi, J K Gupta, Machine Design, Eurasia Publication House,(2005),727-758 [3] PSG College Of Technology, Design Data, Kalaikathir Achangam Pulications,(2013),pp. 7.58-7.70 [4] R.S Khurmi, J K Gupta, Machine Design, Eurasia Publication House,(2005),pp.996-1020. [5] PSG College Of Technology, Design Data, Kalaikathir Achangam Pulications,(2013),pp. 4.1-4.38 Fig 27 Control Panel 1747 www.ijaegt.com