Motor selection / conveyor belt
EMS mini project final report Lecturer: Mohamed Ansari M. Nainar, Dr. MESB443 Electro-Mechanical Systems Section :04A Group members Name: 1-Kemal Vekiloglu ID: ME088669 2- Nima Babaahmadi ID:ME091129 3- Ahmad kamil azeddin ID:ME088767 4- Veerinderjit Singh ID:ME085673
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Motor selection / conveyor belt Table of Contents
Introduction ............................................................................................................................................................ 3 Abstract................................................................................................................................................................... 4 Literature Review ...................................................................................................... ............................................. 4 Analysis and calculations ....................................................................................................................................... 5 Specification and Operating Condition o f the Conveyor Belt Mechanism ..................................................... .... 5 Gear ratio ..................................................... ................................................................. .................................. 5 Required Torque ..................................................... ................................................................. ....................... 6 Moment of Load Inertia .............................................................. ................................................................. . 7 Our design Drawing........................................................ ................................................................. ....................... 8 Conclusion ........................................................... ................................................................. .................................. 9 REFERENCES ............................................................... ................................................................. ....................... 9 APPENDIX .......................................................................................................................................................... 10
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Motor selection / conveyor belt Introduction There are many factors to look into when designing and sizing a motor-drive system. First and foremost, the mechanical design has to be checked and identified. Subsequently, the electromagnetic compatibility has to be ensured. Design factors and design procedures are to be nearly laid out. Then, the selection of motor can be done. Last but not least, the wiring, supply, load and environment consideration must be look into. This design proposed the selection of motor that will drive a conveyor belt t able
Conveyer table is one of the most useful machine in this era, its usage is of extreme important in that it is used in delivering the objects from one place to another without the need of man power, this machine able to bring various weights for different applications depending on the motor used in it, the selected suitable motor will rotate causing the belt which is attached to it with the rollers and in same time deliver the object from end to end of the belt. Conveyer belts are used in multiple application like:
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Factories, in the manufacture line to bring the objective through the procedures.
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Checkout tables in malls, shop counters, it is used to pass the costumer’s goods easily.
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Gym running machines use also this kind of rotating belt.
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Motor selection / conveyor belt Abstract Belt conveyor is the transportation of material from one location to another. Belt conveyor has high load carrying capacity, large length of conveying path, simple design, eas y maintenance and high reliability of operation. Belt Conveyor system is also used in material transport in foundry shop like supply and distribution of molding sand, molds and removal of waste. This paper provides to design the conveyor system used for which includes specification and operating condition of the conveyor belt mechanism, gear ratio, required torque and moment of load inertia.
Literature Review According to Ananth et al, The design of the belt conveyor must begin with an evaluation of the characteristics of the conveyed material and in particular the angle of repose and the angle of surcharge. The angle of repose of a material, also known as the “angle of natural f riction” is the angle at which the material, when heaped freely onto a horizontal surface takes up to the horizontal plane. [1] Very high speeds have meant a large increase in the volumes conveyed. Compared with the load in total there is a reduction in the weight of conveyed material per linear meter of conveyor and therefore there is a reduction in the costs of the structure in the troughing set frames and in the belt itself. The physical characteristics of the conveyed material are the determining factor in calculating the belt speed. With the increase of material lump size, or its abrasiveness, or that of its specific weight, it is necessary to reduce the conveyor belt speed. [1] The conveyor belt changed the face of the industrial economy around the world. Today, it has applicable uses in countless industries, such as transportation and food services. A bucket elevator or conveyer is a mechanism for hauling flow able bulk materials by following an assembly line in horizontal, vertical or inclined direction. According to the survey performed 85% industrial units face difficulties in handling bulk material packaging. The difficulty mainly arises when it is necessary to convey a bulk material through a linear distance as well as a certain height. Conventional ways are responsible for material wasting, time wasting & above all a poor management. In order to overcome those draw backs not only Belt & Bucket conveyers are combined but also artificial intelligence brought in use. Efficiency & accuracy of the system were ensured using the sensor. [2]
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Motor selection / conveyor belt Analysis and calculations
Specification and Operating Condition of the Conveyor Belt Mechanism
Total mass of belt and work
m1 = 15kg
External Force
FA = 0
Frictional coefficient of sliding surfaces
µ=0.3
Roller Diameter
D = 70mm = 0.07m
Roller Mass
m2 = 0.5kg
Belt & Roller efficiency
η=0.9
Belt speed
V=120mm/s ±10%
Motor power supply
Single-Phase 110 VAC 60 Hz
Operating time
6 hours/day
Motor
25W (1/30 HP) Single - Phase
Gear ratio
Speed of the gearhead output shaft NG =
.60 (10±1).60 = .70 =32.74 ± 3.274
The rated speed for the 4 -pole motor at 60 Hz ( Nm) is 1450~1550
i=
1450~1550 = 3.74 ± 3.74
⁄
⁄
=40.26~52.6 From the Gear Efficiency table in Appendix A, the ran ge a gear ratio is i =50 is selected.
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Motor selection / conveyor belt Required Torque
Greatest torque needed on belt conveyor when starting the belt. The friction coefficient ( F ) of the sliding surface,
F = F A +mg ( sin θ + µ cos θ ) = 0 + (15 x 9.81)( sin 0 + 0.3 cos 0) = 44.15 N Load torque TL =
.
= 1.72 N.m
( R efer Appendix A
)
Assuming the safety factor to be 2times TL = 1.72 x 2 = 3.43 Nm
TM =
TL 3.43 = = 0.104 Nm =104 m.Nm 50 0.66
The load torque T L is covert to a value on the motor output shaft to obtain the required torque TM, as follows:
An induction motor has been selected based on the calculation results (Gear ratio i = 50, load torque T L = 3.43 [N.m] ) Induction Motor = 4RK25A – AWMU (Round Shaft Type)
(Refer to Appendix B)
Gearhead = 4GN50K
(Refer to Appendix C )
The starting torque for the 4RK25A – AWMU motor 140 m.Nm which is greater than the required torque which is 104 m.Nm.
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Motor selection / conveyor belt Moment of Load Inertia Belt and Work Moment of Inertia
J m1 = m1 x( ( )/2) = 15 x (( x 0.07) / 2 ) = 183.75x10 -4 kg.m2 1 x m2 x D2 8 1 = x 0.5 x (0.07) 2 8
Roller Moment of Inertia J m2 =
=3.06 x10 -4 Kg.m2
Load Inearia at the gearhead shaft J is calculated as follows:
J= J m1 + ( J m2 x 2 ) = 183.75 x10 -4 + ( 3.06 x10 -4 x 2 ) = 189.88 x10 -4 kg.m2
The permissible load inertia at the motor shaft for 25W (1/30 HP) is 0.31 x 10 -4 kg.m2
(Refer Appendix D) For gear ratio 3:1 – 50:1, J G = J M x i2 J G = is 0.31 x 10 -4 kg.m2 x 502 = 775 x 10 -4 kg.m2 J < JG, the load inertia is less than the permissible inertia, so the motor which is selected does not have any problem and it suitable. Since the motor which was selected has rated torque of 170 m.Nm which is greater than the actual load torque, the motor will operate at higher speed than the rated speed. Therefore, the belt speed is calculated from the speed under no load (approximately (1750 r/min), and thus the selected product have to determine for meet the required specification. V=
1750 70 = = 128 mm/s 60 60 50
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Motor selection / conveyor belt From the calculation, it confirms that the motor meets the specifications. Based on the calculation 4RK25A – AWMU (Round Shaft Type) and 4GN50K are selected as the motor and gearhead respectively.
Our design Drawing
Motor attached to the mechanism Front view of the conveyer belt
Isometric view of the conveyer belt
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Motor selection / conveyor belt Conclusion To sum up with the process of motor selection theory and calculation wise was successfully understood. And the objectives behind the anal ysis to be done in accordance to procedure and the ability to obtain information from the motor selection catalogue had been accomplished
REFERENCES
INTERNET: http://www.orientalmotor.com/products/CatalogPdfs.htm INTERNET: http://www.businessmagnet.co.uk/company/shoppingtrolley131349.htm
ELECTRIC MACHINERY FUNDEMENTALS, STEPHAN J. CHAPMAN, FIFTH EDITION
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Motor selection / conveyor belt APPENDIX APPENDIX A
Table for Gearhead Efficiency
APPENDIX B
Table for Motor Selection
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Motor selection / conveyor belt
APPENDIX C
Table for Gearhead
APPENDIX D
Table for The permissible load inertia at the motor shaft for 25W (1/30 HP)
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