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@IJRTER-2016, All Rights Reserved 43
DESIGN & ANALYSIS OF SINGLE STAGE INDUSTRIAL
HELICAL GEARBOX CASING
Rahul Yashwant Banekar1, Prof.A.C.Mattikali2 1M.Tech.,Mechanical Engg. Dept., MMEC, Belagavi
2 Assistant Prof. Mechanical Engg. Dept. MMEC, Belagavi
Abstract— This paper contains the study of structural analysis of a single stage industrial Helical
gearbox casing using Finite Element Analysis (FEA) Method. Gearbox casing is plays an important
role in power transmission system. Thus the strength, weight, manufacturability and cost of gearbox
casing are an important factor is to be taken while designing. The 3D model is prepared by using
Pro-E creo2.0 pre-processing is prepared by using Hypermesh 11.0 while FEM is solved by using
Ansys 14.5 solver. It was statically analyzed using simulation software Altair Hypermesh and Ansys.
Static analysis is to find out the total amount of stresses and displacement of gearbox casing and End
cover.
Keywords—Gearbox casing, FEA, Optimization, Static analysis, Pro-E creo, Hypermesh, Ansys,
I. INTRODUCTION
The casing encloses different sets of helical gears, bearings to support the shafts. This Gear
box is used in all industries to reduce speed and increase torque. Casing is a part of gear box, it
provides support to shaft, bearing and hence the gear loading. It is a fabricated from Fabsteel IS2062
material. This material selection is based on the criteria of strength, rigidity, cost etc. For casting,
there are many factors to be considered for better result such as material properties, mechanical
properties, chemical composition, fluidity, boundary clearance, thermal properties, etc. to fulfill all
this criteria. The Objective of this project to optimize and find out the effective design of gearbox
with minimum weight by reducing raw material cost without affecting function and investigate effect
of load on stress, displacement in Gear box through finite element analysis.
Technical Specification- H1-80
H- Helical, 1- Stages, 80-Input to Output center distance.
Table.1.0 Input Data
II. DESIGN CALCULATION
The force on each bearing tabulated as follows, Table 2.0 Bearing forces
Clockwise Rotation
Fx(N) Fy(N) Fz(N) Angle Fr(N)
Shaft 1 Bearing 1 125 0 -382 -71.93 402
Bearing 2 161 -143 -344 -64.96 380
Shaft 2 Bearing 1 -274 143 366 129.79 457
Bearing 2 -12 0 373 91.81 373
Power 1.5Kw
Input Speed 1500 rpm
Output speed 293.54 rpm
Ratio 5.11:1
International Journal of Recent Trends in Engineering & Research (IJRTER) Volume 02, Issue 10; October - 2016 [ISSN: 2455-1457]
@IJRTER-2016, All Rights Reserved 44
III. METHODOLOGY
The problem under consideration will be modeled through three approaches:
A. CAD Modeling
B. Preprocessor using hypermesh
i. Meshing
ii. Boundary Condition and load condition
C. Postprocessor using Ansys
i. Stress plot result
ii. Deformation plot result
3.1 Cad Modeling
3D model is prepared by using Pro-E Creo2.0. The CAD Model of gearbox casing
specification is Length-292mm, Width-120mm, Height- 180mm and thickness 5mm.
Figure 1.0 CAD Model
3.2 Preprocessor
3.2.1 Meshing
3D solid model in STEP file format is imported in Hypermesh. Mesh model is
prepared by using Hypermesh11.0. 2D. tria meshing is carried out on all the inner and outer surfaces
of the geometry, quads splits to trias and then converted to tetras. A 4-node Linear Tetra 3D solid
elements are used to model of Gearbox and End covers. The element size selected for Casing and
End covers mesh is 5 mm
International Journal of Recent Trends in Engineering & Research (IJRTER) Volume 02, Issue 10; October - 2016 [ISSN: 2455-1457]
@IJRTER-2016, All Rights Reserved 45
Figure 2.0 Meshing model of gearboxcasing
3.2.2 Boundary condition
The Horizontal foot mounted Gearbox bottom casing is fix connected to the foundation via
six bolting attachments as shown in fig. 3.0. Resting face is constrained in all degree of freedom.
Boundary conditions can be applied to geometry, including faces, edges, curves, points, mesh points,
vertices, nodes, elements or the entire model. There are various types of load applicable over gearbox
casing. The Static load of transmission gear and drive shaft act on bearing hole it divide into two
parts namely, Radial force and axial force on each gear have to analysis. These loads are applied to
find the actual effect of stress and deformation on gearbox.
Figure 3.0 Constrained Conditions
Bearing Radial forces on the housing are applied on the mass element which is spread
over 120° (60° on each side of bearing resultant force direction) on housing through rigid element.
Bearing Radial Forces on the components in X and Z Direction are applied on the Mass element
International Journal of Recent Trends in Engineering & Research (IJRTER) Volume 02, Issue 10; October - 2016 [ISSN: 2455-1457]
@IJRTER-2016, All Rights Reserved 46
which is connected to Component through Rigid Element at 120° of resultant angle.
Figure 4.0 Loading Conditions
3.1 Postprocessor
The static analysis is performed in hypermesh/Ansys and through applying boundary conditions
and forces which are calculated using kisssoft/Kisssys or analytical calculation. Static analysis of
the gearbox casing to find out the total amount of stresses and deformation of and deformation of
structural component
3.1.1 Stress plot result
(a) Von-mises stress plot
Figure 5.0 Von Mises stress plot
International Journal of Recent Trends in Engineering & Research (IJRTER) Volume 02, Issue 10; October - 2016 [ISSN: 2455-1457]
@IJRTER-2016, All Rights Reserved 47
(b) Bottom Casing stress plot
Figure 6.0 Bottom Casing stress plot
(c) Top casing stress plot
Figure 7.0 Top casing stress plot
International Journal of Recent Trends in Engineering & Research (IJRTER) Volume 02, Issue 10; October - 2016 [ISSN: 2455-1457]
@IJRTER-2016, All Rights Reserved 48
3.1.2 Deformation plot
(a) Overall Displacement
Figure 8.0 Overall Displacement plot
(a) Diplacement plot along ‘x’ Direction
Figure 9.0 Displacement plot along ‘X’ Direction
(b) Diplacement plot along ‘Y’ Direction
Figure 10.0 Diplacement plot along ‘Y’Direction
International Journal of Recent Trends in Engineering & Research (IJRTER) Volume 02, Issue 10; October - 2016 [ISSN: 2455-1457]
@IJRTER-2016, All Rights Reserved 49
(c) Diplacement plot along ‘Z’ Direction
Figure 11.0 Diplacement plot along ‘Z’Direction
3.2 Results Table 3.0 Stress plot result
SL
No.
Part Material Allowable
Stress (MPa)
Maximum
Stress (MPa)
1. Assembly Casing FabSteel 250 3.82
2. Top Casing FabSteel 250 3.82
3. Bottom Casing FabSteel 250 2.003
Table 4.0 Displacement Plot result
VI. CONCLUSION
Static analysis of the gearbox casing has done using commercial software hypermesh. Analysis is
to find out the total amount of stresses and deformation of structural components. The gearbox
casing and Cather cover is manufactured from Fab steel (IS: 2062) material. The Max.Von Mises
stress found is 3.82 MPa. Also the maximum displacement of the casing it is found 9.0 micron.
Although the acceptable limits of Stress & displacements are very higher than actually induced
on casing. So still there is more safety factor is there, but we have manufacturing constraint that
we cannot optimize beyond this limit of 5 mm wall thickness. The reason is that, during stress
reliving cycle, plate sizes below 5 mm get Distortions, which results in bending of gearbox
casing plates.
SL
No.
Description Material Max.Displacement
‘mm’
1. Overall Displacement FabSteel 0.0091
2. Displacement along ‘x’
Direction
FabSteel 0.0029
3. Displacement along ‘Y’
Direction
FabSteel 0.0065
4. Displacement along ‘Z’
Direction
FabSteel 0.00325
International Journal of Recent Trends in Engineering & Research (IJRTER) Volume 02, Issue 10; October - 2016 [ISSN: 2455-1457]
@IJRTER-2016, All Rights Reserved 50
Table 4.0 Comparison
SL Description Material Size
mm
Allowable
stress(Mpa)
Max.
stress(Mpa)
Displacemnt
In mm
Weight
kg
1. Traditional
Design
FG260 L=347
W=308
h=203
260 5.687 0.0027 32.96
2. Optimum
Design
FabSteel L=292
W=190
h=120
250 3.820 0.0090 26.33
From above comparison table it can clearly conclude that the optimum design is better than the
traditional one in weight factor.
AKNOWLEDGEMENT
It gives me great pleasure to present this paper on “Design and Analysis of single stage
Industrial helical gearbox casing”. I am very much obliged to contributors for developing and
maintaining the IJRTER International Journals. I will fail in my duty if I won't acknowledge a great
sense of gratitude to entire staff members in Mechanical Department of MMEC, Belagavi, for their
co-operation. Last but not least, I am also thankful to my parents & friends who directly and
indirectly helped in developing this paper.
REFERENCES 1. Shrenik M. Patil , Prof. S. M. Pise Modal And Stress Analysis Of Differential Gearbox Casing With Optimization
Nov-Dec 2013 At Int. Journal Of Engineering Research And Application.
2. Prof. Dr. M. A. Nasser, Prof. Dr. F. R. Gomaa, Structural Modifications of 1K62 Engine Lathe Gearbox
Casing.Volume-3, issue-2, February 2015.
3. Vasim Bashir Maner, M. M. Mirza, ShrikantPawar Design Analysis And Optimization For Foot Casing Of Gearbox
3rd Irf International Conference, 10th May-2014, Goa, India.
4. DrInż. ZbigniewZdziennicki, DrInż. AndrzejMaciejczyk Design Basic Of Industrial Gear Boxes
5. J.K. Gupta R.S. Khurmi, A Textbook Of Machine Design Eurasia Publishing House, 2005, Page 1066-1079.
6. AGMA 2101 D04, Fundamental Rating Factors and Calculation Methods for Involute Spur and Helical Gear Teeth.
ANSI/AGMA 2101-D04, Reaffirmed January 2010.
7. K. mahadevan, K. Balaveera Reddy, Design Data Hand book, Third edition 1987, CBS Publishers & Distributers
PVT. LTD. Page 168-171
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