DESIGN AND ANALYSIS IN MECHANISM OF TILTING MACHINE

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1 International Journal of Mechanical Engineering and Technology (IJMET) Volume 8, Issue 8, August 2017, pp , Article ID: IJMET_08_08_032 Available online at aeme.com/ijmet/issues.asp?jtype=ijmet&vtyp pe=8&itype=8 ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed DESIGN AND ANALYSIS IN MECHANISM OF CAST TILTING MACHINE V.Balaji, P. Sathyaseelan, P. Sankarganesh Assistant Professor, Department of Mechanical Engineering, Vel Tech Dr.RR & Dr.SR University, Avadi, Chennai-62 ABSTRACT Finished castings should be handled with very much care. Before going for the delivery, the final testing is done on the cast. But in the present scenario while the castings are tilted for checking all the portions, they get damaged and has to be sent for refinishing. To overcome this problem the company is making a machine which will help to tilt the cast easily and also reduces the damages happening to the cast, thus resulting in reduction of cost and labour. Our contribution to this project is to make a mechanism which helps to tilt the cast easily and we should be able to achieve it by using the scrap materials like old crane rope wires, motors, pulleys, gear box, etc. available in the company. Keywords: scrap; wire rope; pulley; tilting; casting. Cite this Article: V.Balaji, P. Sathyaseelan and P. Sankarganesh, Design and Analysis in Mechanism of Cast Tilting Machine, International Journal of Mechanical Engineering and Technology 8(8), 2017, pp MET/issues.asp?JType=IJMET&VType=8&ITy ype=8 1. INTRODUCTION Our company Peekay steel castings (P) Limited manufactures heavy castings.the main challenge faced by the company is to tilt the heavy castings for testing before the delivery. The current way used to tilt the castings is by the crane but it causes many damages to the castings which results refurnishing, which increases the cost of manufacturing, labour effort, and time of manufacturing. It will affect the customers also. In order to reduce all the above problems the company has to reduce the damage causing to the castings, for that company want to manufacture a machine which helps to tilt the castings with less damages. The challenge put forward by the company is that the machine has to be manufactured using the scrap materials available in the company. Our role in the project is to contribute in selection and application of mechanism in cast tilting machine. The company provided scrap materials like motor, gear box, gears, pulleys, wire ropes etc. The machine has to help in tilting of castings with less damage. For that we referred various seminar papers and publications. Keeping in mind materials using for manufacture the machine should be from scrap materials available in the company. After referring journals and publications we selected two mechanisms keeping in mind that the availability of scrap materials in the company. The first mechanism is gear mechanism and editor@iaeme.com

2 V.Balaji, P. Sathyaseelan and P. Sankarganesh second is wire rope pulley mechanism. We calculated whether the two mechanisms will work or not. LITERATURE STUDY Before starting our project we referred journals and publications about similar kind of machines which are being used currently for the cast tilting operations. From that study we selected two papers which match our needs and conditions.the papers are: DESIGN AND ANALYSIS OF FIXTURE FOR HEAVY SHELL TILTING by B. K M Patel, Institute of technology, Nirma University, Ahmedabad. RT4 Reverse Tilting Permanent Mold Casting Machine by CMH manufacturing company. 2. DESIGN AND ANALYSIS OF FIXTURE FOR HEAVY SHELL TILTING Principal of operation of tilting fixture for which design is carried out is based on wire rope pulley mechanism. The machine can tilt only heavy shells. But it can tilt shells less than one ton only. The proposed fixture is basically a cylinder with some part of the cylinder is removed to make a tilting fixture. In this type of fixture wire rope pulley mechanism is used for tilting the heavy vessel. Following design parameters are considered for the designing the fixture. Weight 110 MT Diameter mm Height mm Material - IS 2062 (Grade B) 2.1. RT4 Reverse Tilting Permanent Mold Casting Machine. The principal of operation of tilting fixture for which design is carried out is based on gear mechanism. This machine can tilt castings but less than one ton only. The pinion is attached to the motor. Main gear meshes with the pinion which helps to turn the bed. The main gear is connected to the bed directly. It can tilt only less weight castings. If the load is applied it will result in failure of motor SPECIFICATIONS Maximum mold size=102x64cm Maximum mold weight=816.5 kg Machine weight=4037 kg Tilt speed=7sec AIM AND OBJECTIVE To contribute selection and application of mechanism in the cast tilting machine. The materials obtained to make this machine should only be from the scrap materials available in the company. Cost of production should be reduced to maximum level. The machine should be portable Untrained labours should also be able to operate the machine. The machine should not cause much damage to the castings editor@iaeme.com

3 Design and Analysis in Mechanism of Cast Tilting Machine It should save time and human labour. 3. METHODOLOGY Analyzing of the problem»literature study»collection of scrap materials»selection of mechanism»calculation of mechanism»implementation of mechanism»testing of mechanism. 4. GEAR MECHANISM IN CAST TILTING MACHINE n gear mechanism we are using a wheel and a pinion to rotate the bed of cast tilting machine. Both the wheel and pinion were obtained from the old conveyor belts available in the company. The bed of the machine was obtained from the cast carrying trolley. All the materials are obtained from scrap only. The idea is to transfer the power from the motor to the bed, so that it will be able to tilt the castings. 5. WIRE ROPE PULLEY MECHANISM IN CAST TILTING MACHINE In wire rope pulley mechanism we are using wire rope and pulleys to rotate the bed of cast tilting machine. Both the wire rope and pulleys were obtained from the old crane available in the company. The bed of the machine was obtained from the cast carrying trolley. All the materials are obtained from scrap only. The idea is to transfer the power from the motor to the bed, so that it will be able to tilt the castings. 6. COMPONENT SPECIFICATION The main components used in the machine are: Motor Gear box Wire rope Pulleys 6.1. MOTOR The motor is the main component of the machine. It transmits the power to all the other components of machine. Here we are using an AC standard three-phase induction motor of Kirloskar electric Co. Ltd. Three-phase induction motors are the motors most frequently encountered in industry. They are simple, rugged, low priced and easy to maintain. They run at essentially constant speed from zero to full-load. However, variable frequency electronic drives are being used more control the speed of commercial induction motor. A three-phase induction motor has two main parts, a stationary and a revolving rotor. The rotor is separated from the stator by a small air gap ranges from 0.4 mm to 4 mm, depending on the power of motor. A number of evenly spaced slots, punched out of the internal circumference of the laminations, provide the space for the stator winding. The operation of three-phase induction motor is based upon the application of Faraday Law and Lorentz force on a conductor SELECTION OF MOTOR One of the main aims of this project is to obtain the components from scrap materials. And after going through the scrap materials of the company we were able to find three motors which met our requirements. We are looking for a motor with less r.p.m and good efficiency. We have selected the motor with the serial number 3NAA The reason behind selection of this motor is that while comparing with the above three motors, this motor has the least r.p.m. and the efficiency of the motor is high as compared to the other two editor@iaeme.com

4 V.Balaji, P. Sathyaseelan and P. Sankarganesh 6.2. GEAR B0X Gearbox uses gears and gear trains to provide speed and torque conversions from a rotating power source to another device. Gearboxes are used to increase torque while reducing the speed of a output shaft. This means that the output shaft of a gearbox rotates at a slower rate than the input shaft, and this reduction in speed produces a mechanical advantage, increasing torque. A gearbox can be set up to do the opposite and provide an increase in shaft speed with a reduction of torque. Some of the simplest gearboxes merely change the physical rotational direction of power transmission. A gearbox is an important component of the transmission system of any electrical motor system. It is basically a speed controller which control speed from a high to low. But, it is more strong and powerful output structure. It is a mechanical device, which is used to increase the productive torque and change the revolutions of the motor by per minute ratio. In the assembly of the electric motor system, gearbox has a motor s shaft at its one end. It gives the net outcome of torque and speed through the configuration of the gears of the gearbox, thus the machine to which gearbox is connected moves forward. Mostly gearbox are used to control two functions at a time; one, to increase torque and other, to reduce speed. This results in slower rotation of gearbox s drive-shaft comparable to engine s drive-shaft. This reduced speed result in converting the energy to thrust, which bring rotation in the drive-shaft of the gearbox with more force which causes to increase the torque. This type of gearbox is used then there is a need for a greater speed reduction ratio between non-intersecting crossed axis shafts. The worm drive comes with a worm wheel with a large diameter, and there is a worm screw that meshes with teeth on the worm wheel s peripheral area. Generally, the worm resembles a screw while the wheel has a similar function as one section of a nut. The rotating motion of the worm also causes the wheel to move the same way because of the screw-like movement SELECTION OF GEAR BOX One of the main aims of this project is to obtain the components from scrap materials. And after going through the scrap materials of the company we were able to find four gear boxes which met our requirements. We are looking for a gear box with more reduction ratio. We have selected the gear box with the serial number 4R The reason behind selection of this gear box is that while comparing with the above four gear boxes, this gear box has more reduction ratio as compared to the other three. The speed of the motor is 960r.p.m. is reduced to 16 r.p.m CALCULATION FOR GEAR MECHANISM MOTOR SPECIFICATION Ac standard three - phase induction motor Power = 7.5kW r.p.m.= 960 r.p.m. Pole = 6 1 hp= 746 watt. WORM REDUCER Ratio = 60:1 Since, the rpm provided by motor is feed into gearbox which reduces rpm in ratio 60:1. So, editor@iaeme.com

5 Design and Analysis in Mechanism of Cast Tilting Machine r.p.m. = = 16 rpm SPUR GEAR SPECIFICATIONS:- Pinion Number of teeth (Z 1 ) =30 Pitch circle diameter (D 1 ) =180mm Material Grey cast iron Weight of the bed + weight of the casting = N WHEEL Number of teeth (Z 2 ) =100 Pitch circle diameter (D 2 ) =600mm Material Grey cast iron Pitch Calculation(must be same for two mating gears) Circular pitch (P C ) = πd / Z 2 P C = m Diameter pitch(p d )=Z / D=π / P C P d = tooth / mm Module Pitch (m) M = D / z =600/100 = m Pressure angle (ɸ) = 20 o full depth involute gear tooth CALCULATION OF BEAM STRENGTH (F S ) Addendum 1m 6mm Dedendum 1.25m 7.5mm Working depth 2m 12 mm Minimum total depth 2.25 m 13.5 mm Tooth thickness m 9.42 mm Minimum total clearance 0.25 m 1.5 mm Fillet radius at root 0.4m 2.4 mm Face width 12m 72 mm F S = π m b σ b y m= m b = 0.072m σ b =allowable static stress for medium grade cast iron Table No:5.4 σ b = 70N / mm 2 = N / m 2 y =0.358 = form factor F S =34, N If accurate dynamic load(f d )> beam strength(f s ), then the design not satisfactory F d = N> F S = N editor@iaeme.com

6 V.Balaji, P. Sathyaseelan and P. Sankarganesh Therefore, in this scenario 4 teeth are meshing with each other. So, F S = X 4 = N Applied load = N. Load applied > F S = N > N Therefore, the teeth will not withstand the load, hence resulting in tooth breakage and failure. So our design is not satisfactory CALCULATION OF WIRE ROPE MECHANISM SELECTION OF WIRE ROPE S NO MR13M483 C254T17FB10C 3NAA POLE POWER (kw) r.p.m hp VOLTS AMPS EFFICIENCY (%) DESIGN OF WIRE ROPE SELECTION OF SUITABLE WIRE ROPE 6 X 37 Rope CALCULATION OF DESIGN LOAD Design load = load to be lifted X assumed factor of safety =73575 X 5 Design load = N SELECTION OF WIRE ROPE DIAMETER (d) Taking the design load as the breaking strength, the wire rope diameter is selected as 20mm. d = 20mm for tensile strength of wire, σ u = 175 to 190 kgf/mm CALCULATION OF SHEAVE DIAMETER (D) D min / d = 15 [for velocity upto 50 m/ min] Since the given lifting speed is 7.5 m/min Therefore, D min / d ratio should be modified. ModifiedD min / d = 15 X (1.08) [7.5 / 50 = 0.15] D min / d = The sheave diameter (D) = 14 X d editor@iaeme.com

7 Design and Analysis in Mechanism of Cast Tilting Machine =14 X 20 D=280 mm SELECTION OF THE AREA OF THE USEFUL CROSS-SECTION OF THE ROPE (A) A = 0..4 X d 2 =0.4 X (20) 2 A =160 mm CALCULATION OF WIRE DIAMETER (d w ) Wire diameter, d w = 0.89 mm SELECTION OF WEIGHT OF ROPE (W r ) Approximate mass = 1.58 kgf / m Weight of the rope / m = 1.58 X 9.81 =15.49 N / m Weight of the rope (W r ) = X 14 = N CALCULATION OF VARIOUS LOADS Direct load, W d = W + W r = W d = N Bending load, W b = σ b X A W b = N Acceleration load, W a = a = Acceleration of the load a = = X a editor@iaeme.com

8 V.Balaji, P. Sathyaseelan and P. Sankarganesh a=0.015 m /s 2 W a = N Starting Load (W st ) W st = N CALCULATION OF EFFECTIVE LOADS ON THE ROPE Effective load during normal working W en = N Effective load during acceleration of the load W ea = N Effective load during starting W est = N CALCULATION OF WORKING FACTOR OF SAFETY Working factor of safety = ( ) CHECK FOR SAFE DESIGN For class 1 the recommended factor of safety = 3.5 So, 3.5 < 3.75 (FSW) Since the working factor of safety of is greater than the recommended factor of safety, therefore, the design is safe PULLEY A pulley is a wheel on an axle or shaft that is designed to support movement and change of direction of a taut cable, supporting shell is referred to as a block. A pulley may also be called a sheave or drum and may have a groove or grooves between two flanges around its circumference. The drive element of a pulley system can be a rope, cable, belt, or chain that runs over the pulley inside the groove or grooves. A belt and pulley system is characterized by two or more pulleys in common to a belt. This allows for mechanical power, torque, and speed to be transmitted across axles SELECTION OF PULLEY Here we are using 5 pulleys of diameter 280 mm. CALCULATION OF SHEAVE DIAMETER (D) Since the given lifting speed is 7.5 m/min Therefore, D min / d ratio should be modified. ModifiedD min / d = 15 X (1.08) [7.5 / 50 = 0.15] =15 X (1.08) = (.). D min / d = Wire rope diameter (d) = 20 mm [from above wire rope calculation step No 3] The sheave diameter (D) = 14 X d editor@iaeme.com

9 Design and Analysis in Mechanism of Cast Tilting Machine =14 X 20 D=280 mm CALCULATION OF TORQUE The idea of calculation of the torque is that whether the motor and gear box is able to tilt the castings or not. For that we calculated the torque on both ends starting from the motor and gear box. On the other end we are calculating the torque of the bed and castings of cast tilting machine. If the torque of the motor and gear box is greater than the torque of bed and casting then we can prove that the machine can tilt the castings. If not the design is a failure TORQUE OF MOTOR P r.p.m. = 7.5 kw = 960 r.p.m. P = 2 60 T = 60 2 = = T = N-m Motor torque = N-m TORQUE OF GEAR BOX Ratio = 60:1 Torque of gear box = = X 60=4476 N-m TORQUE OF BED AND CASTING Casting 1 Material stainless steel 304 Mass density 8030 kg / m 3 Mass moment of inertia of the hollow cylinder casting Pipe = X m X (R2 r 2 ) Mass of hollow cylinder casting (m) = ρ π R 2 r 2 ) h m = kg Torque = I X α Calculation for angle to be tilted and angular acceleration (α) Where, ω = ϴ ϴ = angle to be tilted t = 8 sec editor@iaeme.com

10 V.Balaji, P. Sathyaseelan and P. Sankarganesh x = distance to be turned = 1.17m r = distance from center of machine bed to end of machine bed = 0. 75m ϴ= ϴ= 2 rad Angular velocity (ω )= ϴ = = Angular acceleration (α) = ω = 16 ω = rad / sec t 2 = time required to attain the above angular velocity = 5 sec t 1 = initial time = 0 sec α =. α = rad / s 2 Torque = I X α I = kg m 2 α = rad / s 2 Torque = X Torque = Nm Nm<4476Nm Torque required by the casting and bed is Nmwhich is less than the output torque of gear box, 4476Nm. So the tilting can be done successfully. angular velocity (ω )= ϴ ω = 16 ω = rad / sec Angular acceleration (α) = t 2 = time required to attain the above angular velocity = 5 sec t 1 = initial time = 0 sec α = rad / s 2 Torque = I X α = X Torque = Nm Nm<4476Nm Torque = Nm Nm < 4476Nm editor@iaeme.com

11 Design and Analysis in Mechanism of Cast Tilting Machine Torque required by the casting and bed is Nm which is less than the output torque of gear box, 4476Nm. So the tilting can be done successfully. 7. CONCLUSION The machine was completely made from scrap materials, So we were able to reduce the production cost to the maximum. Now the company is testing this machine for the period of six months then it will be put to the real life scenario of the company. The first mechanism failed only because in the scrap the gear available was bit small otherwise it would also be a working model. In the case of wire rope pulley mechanism also, if bigger size pulley was available then we would be able to handle more load. Now after making this machine the work load of labours have decreased and to operate this machine there is no need of a trained person. The machine helps a lot to save lot of time and money for the company. REFERENCES [1] Design And Analysis of Fixture for Heavy Shell Tilting by B. K M Patel, Institute of technology, Nirma University, Ahmedabad. [2] RT4 Reverse Tilting Permanent Mold Casting Machine by CMH manufacturing company [3] J. J. Uicker; G. R. Pennock; J. E. Shigley (2003). Theory of Machines and Mechanisms (3rd ed.). New York: Oxford University Press. [4] Chiasson, John (2005). Modeling and High-Performance Control of Electric Machines (Online ed.). Wiley. ISBN X. [5] Fitzgerald, A.E.; Kingsley, Charles, Jr.; Umans, Stephen D. (2003). Electric Machinery (6th ed.). McGraw-Hill [6] Feyrer, K.: Wire Ropes, Tension, Endurance, Reliability. Springer Berlin, Heidelberg, New York 2007 [7] Dynamics, Theory and Applications by T.R. Kane and D.A. Levinson, 1985, pp : [8] Design Data: Data Book Of Engineers By PSG College-Kalaikathir Achchagam Coimbator [9] [10] [11] Theory of Machine. By: R.S. Khurmi and J. K. Gupta. 4- Kinematics and Dynamics of Machines. By: G.H. Martin. [12] Akshay Bharadwaj Krishna, Akshay Prashant Pawgi, Shikhar Gupta and Narendiranath Babu T, Design and Analysis of a Bascule Bridge using Finite Element Method, International Journal of Mechanical Engineering and Technology, 8(7), 2017, pp [13] N.Vijaya Rami Reddy, K.Sudhakar Reddy, A.Chinna Mahammad Basha, B. Rajnaveen, Design And Analysis of Composite Leaf Spring For Military Jeep. International Journal of Mechanical Engineering and Technology, 8(4), 2017, pp editor@iaeme.com

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STRUCTURAL ANALYSIS OF SPUR GEAR USING FEM International Journal of Mechanical Engineering and Technology (IJMET) Volume 7, Issue 6, November December 2016, pp.01 08, Article ID: IJMET_07_06_001 Available online at http://www.iaeme.com/ijmet/issues.asp?jtype=ijmet&vtype=7&itype=6