Abstract
Abstract: The aim of this paper is to study existing Belt conveyor system and optimize the critical parts like Roller, L-channels and support, to minimize the overall weight of assembly. Paper also involves geometrical and finite element modeling of existing design and optimized design. Geometrical modeling was done using CATIA V5R20 and finite Element analysis done in ANSYS14.5. Results of Linear static, Modal and Transient analysis of existing design and optimized design are compared to prove design is safe.In this paper we work on the roller design and optimization. Keyword: Existing roller,Optimized roller 1.Introduction: 1.1Belt Conveyor: Material handling is an important sector of industry, which is consuming a considerable proportion of the total power supply. For instance, material handling contributes about 10% of the total maximum demand in South Africa. Belt conveyors are being employed to form the most important parts of material handling systems because of their high efficiency of transportation. It is significant to reduce the energy consumption or energy cost of material handling sector. This task accordingly depends on the improvement of the energy efficiency of belt conveyors, for they are the main energy consuming components of material handling systems. Consequently, energy efficiency becomes one of the development focuses of the belt conveyor technology [1]. A belt conveyor is a typical energy conversion system from electrical energy to mechanical energy. Its energy efficiency can generally be improved at four levels: performance, operation, equipment, and technology. However, the majority of the technical literature concerning the energy efficiency of belt conveyors focuses on the operational level and the equipment level. In practice, the improvement of equipment efficiency of belt conveyors is achieved mainly by introducing highly efficient equipment. The idler, belt and drive system are the main targets. In the influences on idlers from design, assembly, lubrication, bearing seals, and maintenance are reviewed. Energy saving idlers is proposed and tested in Energy optimized belts are developed in by improving the structure and rubber compounds of the belts. Energy-efficient motors, and variable speed drives (VSDs) are recommended In general, extra investment is needed for the equipment retrofitting or replacement; and the efficiency improvement opportunities are limited to certain equipment [1]. Belt conveyor is a commonly used equipment of continuous transport; it has a high efficiency and large conveying capacity, simpler construction, small amount of maintenance. Can be achieved at different distances, different materials transportation. It is widely used in coal handling system in thermal power plant and other projects [2].Conveyor is used in many industries to transport goods and materials between stages of a process.Using conveyor systems is a good way to reduce the risks of musculoskeletal injury in tasks or processes that involve manual handling, as they reduce the need for repetitive lifting and carrying. Conveyors are a powerful material handling tool. They offer the opportunity to boost productivity, reduce product handling and damage, and minimize labor content in a manufacturing or distribution facility. Conveyors are generally classified as either Unit Load Conveyors that are designed to handle specific uniform units such as cartons or pallets, and Process Conveyors that are designed to handle loose product such as sand, gravel, coffee, cookies, etc. which are fed to machinery for further operations or mixing. It is quite common for manufacturing plants to combine both Process and Unit Load conveyors in its operations [3]. Fig. 1.1 Belt Conveyor Systems 1.2 Principle of Working: Figure 1.2.1 Typical profile of belt conveyors The belt conveyor is an endless belt moving over two end pulleys at fixed positions and used for transporting material horizontally or at an incline up or down. The main components of a belt conveyor are: 1. The belt that forms the moving and supporting surface on which the conveyed material rides. It is the tractive element. The belt should be selected considering the material to be transported. 2. The idlers, which form the supports for the carrying and return stands of the belt. 3. The pulleys that support and move the belt and controls its tension. 4. The drive that imparts power to one or more pulleys to move the belt and its loads. 5. The structure that supports and maintains the alignments of the idlers and pulleys and support the driving machinery. 2. OBJECTIVE: 1.Check design of existing conveyor system. 2.ANSYS APDL codes applied for linear static, modal, transient and optimization analysis. 3. Simulations for linear static Analysis. 4. Simulations for Modal Analysis. 5. Optimization of conveyor assembly for weight reduction. 6. Comparison between existing and optimized design. Problem Statement: The aim of this project is to redesign existing gravity roller conveyor system by designing the critical parts (Roller, Bearing & Frame), to minimize the overall weight of the assembly and to save considerable amount of material. We have to design a conveyor for following specification 1. Load carry capacity = Maximum 10 sugar bag on conveyor Load = 10 X 100kg = 1000 kg 2. Distance to travel = 20 m = 20000 mm 3. Height to lift = 7 m max = 7000 mm 4. Width of conveyor = 500 mm Failure most of cases happen in roller of conveyor which is made up of steel. Fig. Roller Detail Loading on the roller 4 DESIGN OF ROLLER: 4.1 Material – MS E = 2.10*105 Mpa, ρ= 7860 Kg/m3, Syt = 590 Mpa Considering uniformly distributed load & FOS = 2 Allowable Stress (σall) = Syt / Fs =590/2=295 Mpa 4.2 Maximum Stress Calculation for given condition W= 1000/2= 500kg (Load act on 2 rollers at a time) D1= Outer diameter of roller = 61 mm D2 = Inner diameter of roller = 51 mm w = Width of roller = 730 mm y = Distance from neutral axis = 0.061/2 = 0.0305 Considering uniformly distributed load, Maximum Moment (Mmax) = W*L2/8 = (500*9.81*0.732)/8 Mmax = 326.73 Nm Moment of Inertia (I) =П (D14 - D24)/64 = П (0.0614 – 0.0514)/64 I = 3.476*10-7 m4 Maximum bending stress σb = Mmax * y/ I = 326.73 * 0.0305/ 3.476*10-7 σb = 28.66 Mpa 4.3 Checking Factor of Safety for design- Fs = σall / σb = 295/28.66 Fs =10.29 As Calculated Fs is greater than assumed Fs, Selected Material can be considered as safe. 5. Result from ANSYS 14.0 Deformation in old roller Fig.Deformation in old roller Stress in old roller Fig.Stress on old roller 6 OPTIMIZATION DESIGN OF ROLLER: 6.1 Material – MS E = 2.10*105 Mpa, ρ= 7860 Kg/m3, Syt = 590 Mpa Considering uniformly distributed load & FOS = 2 Allowable Stress (σall) = Syt / Fs =590/2=295 Mpa