Murugadass Project

OPTIMIZATION OF THE WEIGHT OF THE OPTIMIZATION OF THE WEIGHT OF THE POWER PRESS USING ANSYS & PRO-EPOWER PRESS USING ANSYS & PRO-E

BHARATHIYAR COLLEGE OF ENGINEERING & TECHNOLOGYBHARATHIYAR COLLEGE OF ENGINEERING & TECHNOLOGY

KARAIKALKARAIKAL

UNDER THE GUIDANCE OF Mr. G.KARTHIKEYAN

SENIOR LECTURERDEPT OF MECHANICAL ENGG

PRESENTED BY

K.MURUGADASS

The project focuses on the optimization of the weight of a C Frame Hydraulic Power Press using ANSYS and PRO/E. The need for the project is that with heavy cost cutting going on, on every aspect of production companies, it is essential to reduce the cost of manufacturing a component or a machine by properly calculating the amount of material used to manufacture it. Here in this case, the material weight used to manufacture the frame of the C Frame Hydraulic Power Press is reduced by analyzing the power press by applying load on it virtually with all the boundary conditions in place.

Then by calculating the deflection and stress on every part of the power press, the material weight is reduced by reducing the thickness of the frame and the thickness of the bed. Then finally with constant deflection and stress in mind, the weight reduction is stopped. Then the weight before analysis and after analysis is calculated and the difference is observed. Then the cost saved is calculated and the graphs for the observed values are plotted out.

PRESS TOOLSPRESS TOOLS Press machines and press tools are considered as a back

bone of the modern machine shop of large industry set up, producing wide variety of articles such as vehicle bodies, electrical accessories and furniture. At high production rate.

Wide variety of machines are built because of the growing typical demand, expansion and progress. Press working does not involve heating of part, close and high surface finish can be obtained on the part. Press work parts do not require any machining also.

POWER PRESSPOWER PRESS Power press are used for producing large quantities of

articles quickly, accurately and economically from the cold working of mild steel and other ductile materials. The components produced range over an extremely wide field and are used throughout industry.

It is also necessary to plan the operations to reduce scrap material to a minimum and to use waste material for other smaller pressings. For any operations to be performed on press, the selection of the proper press and the design of the tool or die to be mounted on it are very important.

PRO/ENGINEER WILDFIRE

Pro/Engineer wildfire is a powerful program used to

create complex designs with a great precision. We can use

the powerful tools of Pro/Engineer wildfire to capture the

design intent of any complex model by incorporating

intelligence into the design.

To make the design process simple and quick, generally a design process consists of the following steps

Sketching using the basic sketch entities.

Converting the sketch into features and parts.

Assembling different parts and analyzing them.

Documentation of parts and the assembly in terms of

drawing views.

Manufacturing the final part and assembly.

ASSEMBLY MODELLINGASSEMBLY MODELLINGAn assembly is defined as a design consisting of more than one component bonded together at their respective working positions. These assembly designs are created in the assembly mode of Pro/Engineer.

Top-Down Approach:

This is the method of assembling the components in which the components of the assembly are created in the same assembly file. In this type of approach of assembly, the components are created in the assembly file and then assembled using the assembly constraints. The parts we create in the assembly mode are saved in .prt files.

BBottom-Up Approach:

This is the method of assembling the components that are created as separate parts in the part mode and are saved as .prt files. Once all the parts of an assembly have been created, we create a new assembly file (.asm) and then assemble constraints available in the assembly mode to create the assembly. Since the assembly file has information related only to the assembling of components. This file is not very heavy and therefore requires less hard disk space.

Here in this project we are using Bottom-Up Approach

ANSYSANSYS  ANSYS is a large-scale multi-purpose finite element

computer program , which may be used for solving several problems. The analysis capabilities of ANSYS include the ability to solve

static and dynamic structural analysis

steady state and transient heat transfer problems

static or time varying magnetic analysis

various types of field and coupled field applications etc.

PERFORMING A STATIC ANALYSISPERFORMING A STATIC ANALYSIS

The procedure for a static analysis consists of these tasks:

Build the Model

Set Solution Controls

Set Additional Solution Options

Apply the Loads

Solve the Analysis

ELEMENT TYPESELEMENT TYPESDifferent types of elements are used for analysis. On meshing a continuum, it is divided in to small elements and these elements are solved to obtain the described solution. The various types of elements are listed

LineTriangularQuadrilateralParallelogramRectangular prismHexahedron

DESCRIPTION OF THE PROBLEMDESCRIPTION OF THE PROBLEM Here a ‘C’ framed power press is taken into

consideration, and in this project we consider punching operation. While punching, the Ram has to travel from the punch holder to the die block. So in this operation, due to the ram speed and force, some deflections are undergone in the structure.

Here we are going to consider the deflections and stresses in the structure and minimize the material wherever there is no deflection and stress. Hence this reduces the weight of the power press and minimizes the cost of the production.

SOURCE OF THE PROJECTSOURCE OF THE PROJECT

The source of the project is from the company,

BHARATH PRESSINGS, Pvt Ltd, Chennai. The

dimensions and specifications of a 10 tonne capacity press

are obtained from this company. The manufacturer of the

C framed power press is BEMCO PRESSES, Pune

NEED OF THE PROJECTNEED OF THE PROJECT Standard C-Frame presses bring hydraulic precision

and control to most pressroom applications including punching, blanking, coining, forming, bending, drawing and assembly work. The C- frame press is considered because of its high rigid frame construction and also the maintenance cost of the press is less compared to other.

For economical production of quantities of pressings, consideration has to be given to the rate of production, the cost of the press tools to be employed and the expenditure involved in setting them.

In most of the presses there are some excess materials

where no stress is acting there. This increases the material

weight and cost for the manufacturer. So these materials

should be removed to reduce the material usage to

increase the profit for the manufacturer.

METHODOLOGYMETHODOLOGY• First the dimensions and specifications for a C framed

power press is taken from a manufacturer. • Using the specifications and dimensions a C framed

power press is modeled in pro/E.• Model is imported to Ansys package for analysis. • The static load condition is considered for analysis. • As per the specifications the load is applied on the ram

and the deflections and stresses acting on the structure are calculated.

According to the analysis results, the materials can be removed as the defections are less in certain areas.

Again an analysis is made to the modified press, so that the deflections and stresses underwent by this modified one is same as that of the original model.

Finally the stresses and deflections of the presses are compared.

DESIGN SPECIFICATIONSDESIGN SPECIFICATIONS

Frame thickness - 25mm

Total Height of the press - 1990mm

Area of the bed - 600x400mm

Bed thickness - 100mm

Breadth of the frame - 1030mm

Floor to top of bed - 710mm

Diameter of the Ram - 120mm

Stroke Length - 300mm

PHOTOGRAPHIC VIEW OF ‘C’ FRAME POWER PRESS

Model HCP – 10

Technical specifications of the power pressTechnical specifications of the power press

Hydraulic 'C' Frame Type Presses :

Capacity (Tons) -10

Stroke Length (mm) -300

Approach Speed (mm/sec.) -30 – 40

Pressing Speed (mm/sec.) -5 to 8

Return Speed (mm/sec.) -30 - 40

Electric Motor (H.P.) -5

Weight of the Press (Tons) -2 to 2.5

MODELING OF POWER PRESS The modeling of power press is carried out in

Pro/Engineer software. Pro/Engineer wildfire is a

feature based solid modeling tool using Bottom-Up

Approach. The use of the feature-based property

provides greater flexibility to the parts created. The

accuracy rate is high compared to other modeling

software’s. According to these features the modeling

of the power press is done in Pro/Engineer software.

ANALYSIS OF POWER PRESSANALYSIS OF POWER PRESS The procedure in using an FEA program consists of three

essential stages.Preparation of the model data (Pre-Processing)Analysis of the model.Assessment of the result (Post-Processing)

Required inputs to the pre-processor include:Geometric parametersLoading characteristicsBoundary conditionsMaterial properties

ELEMENT DESCRIPTIONELEMENT DESCRIPTION

SOLID45 SOLID45 is used for the 3-D modeling of solid structures.

The element is defined by eight nodes having three degrees of freedom at each node: translations in the nodal x, y, and z directions.

ELEMENT DESCRIPTIONELEMENT DESCRIPTION

Problem Specification

Applicable ANSYS Products: ANSYS Multi physics, ANSYS Mechanical, ANSYS Structural, ANSYS ED

Discipline: Structural

Analysis Type: Static

Element Types Used: Solid brick 8 node 45

ANSYS Features Demonstrated: solid modeling including primitives, Boolean operations, and fillets; tapered pressure load; deformed shape and stress displays; listing of reaction forces; examination of structural energy error

PROBLEM DESCRIPTIONPROBLEM DESCRIPTIONThe C-framed power press is modeled in PRO/E software package according the specifications, and it is analyzed in ANSYS environment. Here the stress and deformations are calculated and according to this the frame thickness, web thickness, material, weight are modified.

GivenGiven

The material properties of the power press:

Material used: Steel

Young’s Modulus : 2.1*105 N/mm2

Poisson’s Ratio : 0.3

Density : 7860Kg/metres cube

Thermal expansion : 0.000017

SUMMARY OF STEPSSUMMARY OF STEPSBuild geometryThe Pro/E software is used to model the power press

according to the dimensions.After modeling, save a copy in IGES format in solid.The IGES format is imported into ANSYS environment.Define MaterialsGenerate MeshApply LoadsObtain SolutionReview Results

TRIALS MADETRIALS MADE Four number of trials where made using following dimension criteria.Results for cases bed thickness 100mm, frame thickness 25mm and bed

thickness 70mm, frame thickness 18mm are presented and compared for optimization

BED THICKNESS

100mm 90mm 80mm 70mm

FRAME THICKNESS

25mm 22mm 19mm 18mm

Results for cases bed thickness 100mm, frame thickness 25mm and bed thickness 70mm, frame thickness 18mm are presented and compared for optimization

CASE 1:For frame thickness : 25mmBed thickness : 100mm

CASE 2:For frame thickness : 18mmBed thickness : 70mm

CASE 1:For frame thickness : 25mmBed thickness : 100mm

CASE 2:For frame thickness : 18mmBed thickness : 70mm

PARAMETERS EXISTING MODIFIED

BED THICKNESS 100 mm 70mm

FRAME THICKNESS 25mm 18mm

WEIGHT 1.92 tones 1.66 tones

STRESS 56.68N/mm2 56.42N/mm2

DEFLECTION 1.533mm 1.647mm

FOR COMMON LOAD CONDITION: 10 TONES

STRESS vs BED THICKNESS

56.2

56.3

56.4

56.5

56.6

56.7

100 90 80 70

BED THICKNESS

ST

RE

SS

STRESS

DEFLECTION vs FRAME THICKNESS

1.45

1.5

1.55

1.6

1.65

1.7

25 22 19 18

DEFLECTION

FRAME THICKNESS

DEFLECTION

RESULTRESULT

In the existing design,

Maximum stress acting on the structure is 56.68 N/mm2 Maximum deflection is 1.533mm.

In the suggested design,

Maximum stress acting on the structure is 56.42 N/mm2

Maximum deflection is 1.647mm.

Regarding static analysis, the design is safe. In this design, the decrease in frame and bed thickness is done. So there is a reduction in weight.

The reduction in weight is 13.5%. finally we conclude that this design is the better design.

Existing weight of the power press: 1920Kg

Modified weight of the power press: 1660Kg

In this project the C framed Power Press is studied and the design was done as per the dimensions. The model of the power press is done in PRO/ENGINEER software. The analysis of the power press is carried out using ANSYS package. Finally the modified design is obtained by changing or varying the frame thickness and bed thickness and thus the objective of the study is achieved.