Design and Analysis of Transfer Trolley for Material Handling

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Volume 2, Special Issue 1 MEPCON 2015

166

Available online at www.ijiere.com

International Journal of Innovative and Emerging

Research in Engineering

e-ISSN: 2394 - 3343 p-ISSN: 2394 - 5494

Design and Analysis of Transfer Trolley for

Material Handling

Kaustubh V. Wankhade

a

_{and N. A. Wankhade}

b

a_{ME-Mechanical (CAD/CAM) Scholar, PRMIT&R, Badnera, Amravati, Maharashtra, India} b_{Associate professor, PRMIT&R, Badnera, Amravati, Maharashtra, India}

ABSTRACT:

In casting industries most difficult task is to carry and pour molten metal into moulds also risk associates with this process of molten metal handling is more. At present this task is operated manually by crucibles and various ladles like gear ladle for both small and medium scale industries. Now a day’s manpower requirement for this process is minimum two workers for ladle handling and one for assisting and putting stand to pour into mould. Our aim is to reduce manpower by employing transfer trolley mechanism for molten metal handling and pouring so as only one worker should be able to perform this operation. It will make this process more efficient and user friendly. As the labor requirement is reduced so alternately the cost of production is also reduced. Materials are selected, analytical and mathematical calculations were calculated, some perimeters are assumed and some found out. And then design is constructed in CAD software based on mathematical calculations.

Keywords: Material needed for construction, Design of Crucible, Design of frame, Pipe thickness, Gear design, CAD.

I. INTRODUCTION

In foundries or in casting industries metal is melted in furnace like cupola furnace and collected into the vessel called ladle. Then ladle is handled, carried to moulds and pour the molten metal into cavity to make casting. Currently it requires crucibles or ladles for this operation. But it is not efficient as at least three workers are needed for this operation. The aim of our research is to minimize the manpower requirement so that only one personal can do the same job reliably and with less risk. And hence we design a transfer trolley which is capable of collecting molten metal into the cylindrical vessel which is mounted on frame work which is tilted with the help of gearing mechanism to accomplish pouring molten metal into guide way which is nothing but a channel which has adjustable height, hence the molten metal poured into cavity. The major considerations in the casting designing is quality of product and yield of the casting [1]. Caster wheels is solid rubber wheels of high strength and have higher load carrying capacity which is more than two tons to sustaining extra weight of frame, hoist and trolley. Caster flat tyre wheels are applicable in soft soil and also gravel drive ways [2]. Workers use lifting devices for handling hot rolled product but difficulties arises while handling, because different size and dimension for different products from mills to desired locations [3]. casting is a key process in manufacturing as a wide range material are available and suitable and also an alternatives available for economic prospect. The trolley speed can increased by increasing the gearbox speed and by reducing failure in loading trolley and gearbox [4]. By using 3D-contact finite element method the time variable stiffness curves of meshing gears and the profile errors where determine by gear precision [5]. Also with the help of integration of systematic method and solving tool like TRIZ increases the casting process optimization efficiency [6].

II. MATERIAL NEEDED FOR CONSTRUCTION

Materials are selected scientifically for required properties. Frame is made from square steel pipe. Wheels are made from caster which is nothing but hard rubber having higher strength. Caster wheels are applicable or adaptable in foundry environment. Vessel is made from cast iron, fire clay is needed in layering the inner side of vessel.

III. BRIEF OF DESIGN

Design is made in step by step manner. Situation and limitation like aisle width, distance between two aisles are studied and finalize the basic dimensions and assume it for calculating other parameters. This design is divided into parts like design of crucible (vessel), designing a frame dimensions and finding out thickness of square pipe and also the gearing design for tilting the vessel to pour molten metal into channel.

A. Design of Crucible (Vessel)

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167 Calculation-

Design is to handle 300 Kg molten metal, so with clearance we assume mass as 370 Kg. Density of molten steel, 𝜌 = 7000 𝐾𝑔/𝑚3

But, 𝒎𝒂𝒔𝒔 = 𝒗𝒐𝒍𝒖𝒎𝒆 ∗ 𝒅𝒆𝒏𝒔𝒊𝒕𝒚

𝑣𝑜𝑙𝑢𝑚𝑒 = 𝑚𝑎𝑠𝑠

𝑑𝑒𝑛𝑠𝑖𝑡𝑦=

𝑚 𝜌

𝑣𝑜𝑙𝑢𝑚𝑒 = 370

7000= 0.05285 𝑚

3

As per design considerations we assume diameter of crucible (cylinder), d =400mm = 0.4m

Hence, to find height of crucible (H).

𝑣𝑜𝑙𝑢𝑚𝑒 𝑜𝑓 𝑐𝑟𝑢𝑐𝑖𝑏𝑙𝑒 (𝑐𝑦𝑙𝑖𝑛𝑑𝑒𝑟) = 𝜋𝑟2_𝐻

0.05285 = 𝜋 ∗ 0.22∗ 𝐻

𝐻 = 0.421 𝑚 = 421 𝑚𝑚 To find thickness of crucible,

𝑡 = 𝑃∗𝑑

2∗𝜎𝑡𝑐=

0.2∗400

2∗17.5 = 2.285 𝑚𝑚

Since the thickness of cast iron casting should not be less than 6 mm. Therefore we shall take thickness of crucible, 𝒕 = 𝟔 𝒎𝒎

B. Frame Design and Pipe Thickness

Frame length is assume to be 900 mm and width is 500 mm. For the framework on which vessel is mounted exerts down force of nearly 3000 N on frame which cause frame to bend and hence we find out the thickness of the square pipe.

Calculation- Force system is as shown in fig below.

Figure1. Force Distribution on Trolley Frame.

Tan 𝜃 =𝑜𝑝𝑝 𝑠𝑖𝑑𝑒 𝑎𝑑𝑗 𝑠𝑖𝑑𝑒 Tan 𝜃 =1200

300 𝜃 = 𝑡𝑎𝑛−1 ₍1200

300) = 75.96° Considering vertical loads only

Figure2. Load Diagram

Taking moment about point ‘A’

𝑅𝐵∗ 900 = 100 ∗ 200 + 1455.19 ∗ 300 + 1455.19 ∗ 900

𝑅𝐵 = 1962.48𝑁 Summation ‘Y’ is equal to zero,

∑ 𝑌 = 𝑜, 𝑅𝐴+ 𝑅𝐵= 100 + 1455.19 + 1455.19

𝑅𝐴+ 1962.48 = 3010.38 𝑅𝐴= 1047.9𝑁

Load on front wheels, 𝑅𝐴1= 𝑅𝐴2= 𝑅𝐴

2 =

1047.9

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168 Load on front wheels, 𝑅𝐵1= 𝑅𝐵2=

𝑅𝐵

2 =

1962.48

2 = 981.24𝑁

Bending moment at point C, = 𝑅𝐴1∗ 200 = 𝟏𝟎𝟒. 𝟕𝟗 ∗ 𝟏𝟎𝟑 _{𝑵. 𝒎𝒎}

Bending moment at point D, = 𝑅𝐴1∗ 300 − 100 ∗ 100 = 523.95 ∗ 300 − 100 ∗ 100 = 𝟏𝟒𝟕. 𝟏𝟖𝟓 ∗ 𝟏𝟎𝟑 𝑵. 𝒎𝒎

As the bending moment at point ‘D’ is maximum, hence Maximum bending moment,

ie... M= 𝟏𝟒𝟕. 𝟏𝟖𝟓 ∗ 𝟏𝟎𝟑 _{𝑵. 𝒎𝒎}

section modulus for square pipe or tube,

𝑍 =𝑏4−ℎ4

6𝑏 =

2.56∗106−ℎ4

240

Now, 𝜎𝑏 = 𝑀

𝑍 ...where( 𝜎 = 60𝑁/𝑚𝑚 2₎

60 =147.185∗103∗240 2.56∗106_−ℎ4

ℎ = 37.47𝑚𝑚 wall thickness of square pipe,

𝑡 =𝑏 − ℎ

2 =

40 − 37.47 2 𝑡 = 1.265𝑚𝑚

But standard value for square pipe thickness is 1.3mm

C. Gear design

Gearing or a gear train is employed for achieving tilting mechanism for crucible or vessel. Calculation-

𝑊𝑇 = 3500 N

𝜎𝐴= 𝜎𝐵= 𝜎𝐶=60 Mpa =60 N/𝑚𝑚2 V.R. = 4:2:1

𝑁𝐴 = 60 rpm L = 180 mm b = 14*m

C = 80 K = 1.4 Let,

M = module, 𝐷𝐴 = pitch circle diameter of gear A, 𝐷𝐵 = pitch circle diameter of gear B, 𝐷𝐶 = pitch circle diameter of gear C

We know that centre distance between gear shafts is ‘L’ ·: L = 𝐷𝐴

2 + 𝐷𝐵 + 𝐷𝐶

2 180 = 𝐷𝐴

2 + 2𝐷𝐴 + 4𝐷𝐴

2

𝐷𝐴= 40 𝑚𝑚 = 0.04 𝑚 𝐷𝐵= 2𝐷𝐴= 2 ∗ 40 = 80 𝑚𝑚 𝐷𝐶 = 4𝐷𝐴= 4 ∗ 40 = 160 𝑚𝑚

Since all the gears are made from same material so gear A is weaker and hence we design for gear A, We know that pitch line velocity of the pinion ;

𝑣 =𝜋𝐷𝐴𝑁𝐴

60 =

𝜋∗0.04∗60

60 = 0.1256 m/s

Since v is less than12m/sec hence velocity factor; 𝐶𝑉= 3

3+𝑣=

3

3+0.1256= 0.959 We know that number of teeth on gear A

𝑇𝐴= 𝐷𝐴

𝑚 =

40 𝑚 Tooth form factor for gear A 𝑌𝑃= 0.175 −

0.841 𝑇𝑅

= 0.175 −0.841∗𝑚

40 ....for 20 stub system. = 0.175 − 0.021 ∗ 𝑚 ...(1)

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169 As 𝑊𝑇 = 3500 N

Also 𝑊𝑇= 𝜎𝑊𝐴 ∗ 𝑏 ∗ 𝜋 ∗ 𝑚 ∗ 𝑌𝐴

3500 = 𝜎𝑂𝐴 ∗ 14𝑚 ∗ 𝜋 ∗ 𝑚 ∗ (0.175 − 0.021𝑚) 3500 = (60 ∗ 0.959) ∗ 14𝑚2_{∗ 𝜋 ∗ (0.175 − 0.021𝑚)} 3500 = 442.88𝑚2− 57.14𝑚3

By solving equation by hit and trial method, 𝑚 = 2.87 𝑚𝑚 … … … . . 𝑠𝑎𝑦 4 𝑚𝑚 Therefore, module =4mm

Face width = 14 times module 𝑏 = 14 ∗ 𝑚

= 14 ∗ 4 = 56 𝑚𝑚

No of teeth on gears, For gear A, 𝑇𝐴=

𝐷_𝐴

𝑚 =

40

4 = 10

For gear B, 𝑇𝐵= 𝐷𝐵

𝑚 =

80

4 = 20

For gear C, 𝑇𝐶= 𝐷𝐶

𝑚 =

160

4 = 40 Checking the gear for dynamic and wear load

𝑊𝐷 = 𝑊𝑇+

21𝑣(𝑏𝑐+𝑊_𝑇) 21𝑣+√(𝑏𝑐+𝑊𝑇)

𝑊𝐷 = 3500 +

21∗0.1256(56∗80+3500) 21∗0.1256+√(56∗80+3500)

𝑊𝐷 = 3505.311 𝑁

From equation (1) Tooth form factor,

𝑌𝑃= 0.175 − 0.021 ∗ 𝑚 𝑌𝑃= 0.175 − 0.021 ∗ 4 𝑌𝑃= 0.091

From table (28.8)in machine design by Khurmi and Gupta, flexural endurance limit (𝜎𝑒) for cast iron is 84mpa or 84 N/𝑚𝑚2

Therefore; static load or endurance strength of tooth, 𝑊𝑆= 𝜎𝑒 ∗ 𝑏 ∗ 𝜋 ∗ 𝑚 ∗ 𝑌𝐴

𝑊𝑆= 84 ∗ 56 ∗ 𝜋 ∗ 4 ∗ 0.091 𝑊𝑆= 5379.21 𝑁

We Know that, Ratio factor, 𝑄 = 2𝑉𝑅

𝑉𝑅+1=

2∗2

2+1= 1.33 Now, maximum or limiting load for wear

𝑊𝑊 = 𝐷𝐴∗ 𝑏 ∗ 𝑄 ∗ 𝐾 𝑊𝑊 = 40 ∗ 56 ∗ 1.33 ∗ 1.4

𝑊𝑊 = 4170.88 𝑁

Since both 𝑊𝑆 and 𝑊𝑊 are greater than 𝑊𝐷, therefore the design of gear is safe.

From table (28.1) in machine design by Khurmi and Gupta, standard proportion of gear for module 4mm

1] Addendum =0.8*m =0.8*4 = 3.2mm 2] Dedendum =1*m =1*4 =4mm 3] Working Depth = 1.60*m =1.60*4 =6.4mm 4] Minimum Total Depth = 1.80*m =1.80*4 =7.2mm 5] Tooth Thickness =1.5708*m =1.5708*4 =6.28mm 6] Minimum Clearance =0.2*m =0.2*4 =0.8mm 7] Fillet Radius at Root =0.4*m =0.4*4 =1.6mm

D. Channel

Channel is nothing but the guide way and medium through which molten metal is poured into cavity from vessel. Channel length is depends on distance of pouring point. Here we take length as 1000mm.

IV. MODEL CONSTRUCTION IN CADSOFTWARE

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170 Figure3. Trolley Model Constructed in Creo-Parametric

V. CONCLUSION

Trolley is designed mathematically and model is constructed in CAD software like Creo-Parameric. It is seen that the design is safe and can be implemented in casting industries or foundries for small and medium scale castings. and manpower requirement are also reduced to only one worker so the production cost is also reduced.

REFERENCES

[1] Jean Kor, Xiang Chen, and Henry Hu.Multi-Objective Optimal Gating and Riser Design for Metal-Casting, IEEE Multi-conference on Systems and Control, Saint Petersburg, Russia, page no. 428 – 433, 8-10 July (2009) [2] Sam Hutcheson Design and Construction of a Portable Gantry Hoist, BioResource and Agricultural Engineering

Department, California Polytechnic State University, San Luis Obispo (December 5, 2013).

[3] S E Dhage1*, A V Vanalkar1 and P R Gajbhiye1 2013 Design Consideration For Hot Rolled Product Transfer Mechanism. IJMERR, page no. 204-208, (Vol. 2, No. 4) (October 2013)

[4] Pratik Gulaxea1, N. P. Awate2 2013 Design, Modeling & Analysis Of Gear Box For Material Handling Trolley: A Review, Mechanica Confab, page no. 63-70, Vol. 2, No. 1, (January 2013)

[5] Wang Qing, ZHANG Yi-duly Ding-shi, ZHANG Finite- Element Analysis of Dynamic Characteristics for Coupling Vibration of Gear Transmission Based Element of Stiffness Matrix School of Mechanical Engineering & Automation, Beihang University, Beijing 100083,China,(2008)

[6] Liu Feng, Yang Yi A systematic method for identifying contradiction of casting process, IEEE International Conference on Digital Manufacturing & Automation, page no. 145 – 151, (18-20 Dec. 2010)

[7] Pressure vessels, A textbook of machine design by R.S. Khurmi and J.K. Gupta, Chapter no. 7, page no. 224-260 [8] Pipes and pipe joints, A textbook of machine design by R. S. Khurmi and J.K. Gupta, chapter no. 8, page no.

261-280