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    Stress Based Topology Optimization of 30 Ton C Hook Using FEM.

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    Aravind J
    The document describes a project to perform topology optimization of a 30 ton C-hook lifting structure using finite element analysis. It includes an introduction to topology optimization and C-hooks, a literature review on curved beam stresses, problem definition, methodology, initial design calculations, finite element modeling and analysis, and results showing stress distributions and an optimized topology. The optimized design shows potential stress reductions and material savings through redistributing material only to high stress areas.

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    Stress Based Topology Optimization of 30 Ton C Hook Using FEM.

    Uploaded by

    Aravind J
    119 views48 pages
    The document describes a project to perform topology optimization of a 30 ton C-hook lifting structure using finite element analysis. It includes an introduction to topology optimization and C-hooks, a literature review on curved beam stresses, problem definition, methodology, initial design calculations, finite element modeling and analysis, and results showing stress distributions and an optimized topology. The optimized design shows potential stress reductions and material savings through redistributing material only to high stress areas.

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    Stress based topology optimization of 30 ton c hook using FEM.

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    The document describes a project to perform topology optimization of a 30 ton C-hook lifting structure using finite element analysis. It includes an introduction to topology optimization and C-hooks, a literature review on curved beam stresses, problem definition, methodology, initial design calculations, finite element modeling and analysis, and results showing stress distributions and an optimized topology. The optimized design shows potential stress reductions and material savings through redistributing material only to high stress areas.

    Copyright:

    © All Rights Reserved
    Download as PPTX, PDF, TXT or read online from Scribd
    Download as pptx, pdf, or txt
    119 views48 pages

    Stress Based Topology Optimization of 30 Ton C Hook Using FEM.

    Uploaded by

    Aravind J
    The document describes a project to perform topology optimization of a 30 ton C-hook lifting structure using finite element analysis. It includes an introduction to topology optimization and C-hooks, a literature review on curved beam stresses, problem definition, methodology, initial design calculations, finite element modeling and analysis, and results showing stress distributions and an optimized topology. The optimized design shows potential stress reductions and material savings through redistributing material only to high stress areas.

    Copyright:

    © All Rights Reserved
    Download as PPTX, PDF, TXT or read online from Scribd
    Download as pptx, pdf, or txt
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    The document discusses topology optimization of a 30-ton C-Hook using finite element analysis. It aims to reduce weight and redistribute stresses.

    Topology optimization is a process that optimizes the material distribution within a given design space to obtain the best performance under the given loads and constraints.

    A C-Hook is a lifting device used to grab and lift heavy loads. Its applications include material handling, paper/coil handling. Types include Turner, rotating, J, double and fork C-hooks.

    VISVESVARAYA TECHNOLOGICAL UNIVERSITY K.S.

    INSTITUTE OF TECHNOLOGY
    Jnana Sangama, Belagavi- 590018, Department of Mechanical Engineering
    Karnataka

    Project Title:
    Stress Based Topology Optimization Of 30 Ton C-Hook
    Using Finite Element Analysis
    UNDER THE GUIDANCE OF
    Prof. NAGABHUSHANA M
    ASSOCIATE PROFESSOR

    PROJECT GROUP
    1KS13ME041 JEEVAN REDDY.N.S
    1KS14ME015 ARAVIND J
    1KS14ME113 GOVARDHANA V BHARGAV
    1KS14ME114 BASAVANAGOWDA
    CONTENTS

    • INTRODUCTION
    • LITERATURE REVIEW
    • PROBLEM DEFINITION
    • METHODOLOGY
    • EXPERIMENTAL WORK
    • RESULTS AND DISCUSSIONS
    • REFERENCES
    Introduction
    • Topology optimization is the process of
    optimizing the design parameters with in the
    design space with the main aim of
    redistributing the stresses along with weight
    reduction .
    What is Hook?
    A lifting hook is a device for grabbing and lifting load by means
    of a device such as a hoist or crane .a lifting hook is usually
    equipped with a safety latch to prevent the disengagement of
    the lifting via ropes sling, chain or rope to which the load is
    attached.

    Types of C-Hook
    • Turner c-hook.
    • Rotating c-hook.
    • J-hook.
    • Double c-hook.
    • Fork c-hook.
    • Simple c-hook and Coil-clamps.
    C-Hook Applications:

    • Heavy duty material handling.


    • Paper role handling.
    • Slide coil handling.
    • Close stacking c-hook.
    • Pivoting c-hook.
    A typical C-Hook

    The figure shows Load lifting by a C-


    Hook through overhead Crane
    Structure. Generally C-Hook is used
    for heavy load applications.
    Literature Review
    • Vijendra Kumar etc. al[1] discussed about the importance of curved beams and theories for
    stress estimations. They have applied Winkler’s theory for stress estimations and the same
    is obtained through strain gauge techniques. Both the values are compared to find the
    applicability of the formulae’s and experimental setups. They found close relation of the
    obtained values. Aluminium material is used for test setup. Even analytical calculations are
    carried out along with experimental and finite element analysis to analyze the problem.
    • Amaresh etc, al[2] discussed about analysis and design aspects of lifting members for heavy
    load applications. In his design, truss members are used for designing and analyzing the
    multi scissor arm mechanism using truss concept. The design is optimized based on finite
    element analysis after constructing through three dimensional modelling and later to shell
    meshing . Even the problem is analysed through one dimensional analysis due to its easier
    representation. He has effectively applied both one dimensional technique with link
    elements and two dimensional shell elements to analyze the problem.
    • Shiv Pratap Singh Yadav et. Al[3] detailed the importance of curved beams in the
    engineering industry. They find wide use in Mechanical and Civil structures. Here, they
    developed programs based in ‘C’ Language and the same is validated through Finite Element
    Analysis. The design parameters like radius, length , load , offset etc are considered for
    parameterization of design. Ansys software is used for finite element analysis. Very
    minimum variation is observed between the programmed calculations and finite element
    solutions. These error is also attributed due to the selection of the elements. Finite element
    can ‘t represent a curved geometry. So size of the element also plays very important role in
    the accuracy of the problem.
    Problem Definition & Objectives
    • Topology Optimization of the C-clamp using
    Finite element analysis with the help of
    theoretical design concepts is the main
    definition of the problem.
    • Here the main objective is to find the
    minimum dimensions required for the C-
    clamp for the given load details.
    • Topology optimization.
    Methodology
    • Literature on C-hook designs and probable
    problems.
    • Theoretical calculations for dimensions for the
    c-hook along with pin dimensions.
    • Three dimensional modeling and analysis.
    • Topology optimization of the object using
    Ansys software.
    • Comparison of structural strength and weight
    for initial and optimized design.
    Design Requirements

    • Coil Diameter to be lifted : 2.5m


    • Length of the Coil: 2m
    • Total Coil Weight=30 tons.

    Minimum dimensions required for the C-Frame


    • Length of the C-Frame : 2.3 meter(Minimum gap
    of 300mm at the edge of C-frame)
    • Minimum height of the C-Frame: 1.5m
    Material Specification

    Material Elastic Poison’s Density Yield Allowable


    Specification Modulus ratio Stress Stress(Mpa)
    (Mpa)

    Mild Steel 200Gpa 0.3 7850kg/m3 250 100


    Functioning of C-Hook
    • The C-Clamp is the most common type of coil handling device, and the
    “Balanced C-Clamp” is the most common C-Clamp style.
    • Many years ago, they were made of a single plate with a counterweight
    attached for balance.
    • The first improvement was to install a saddle on the lifting arm. The lifting
    arm is the portion that is inserted into the eye of the coil and actually
    performs the coil lifting.
    • A back plate was installed to alleviate the damage done to the coil wall
    when the leg portion of the C-Hook hit it. This striking of the coil wall
    occurs almost always, and especially when picking up coils of maximum
    width. C-Hooks are designed so that the coil wall of a maximum width coil
    will be approximately one half-inch to one inch away from the leg edge
    when lifting and transporting it. Ideally, a crane operator will - from a
    hundred feet or more away - insert the lifting leg of the C-Hook into the
    eye of the coil without the leading edge (or “nose”) ever touching the coil
    wall, and then stop the insertion process when the coil wall is just a half
    inch or so from striking the back plate. The probability of lifting the coil in
    this manner without damage is extremely low.
    Specifications of the C-Hook
    Segment Representation
    Shear Force and Bending Moment
    Diagrams
    • Total load : 30 tons=30000kgs or 300000N or
    300KN
    • If 300KN is applied on a length of 2300mm,
    the uniformly distributed load value is
    w=300000/2300=130.43N/mm
    • For analysing the segment, each segment is
    assumed to be fixed. The following boundary
    conditions were applied.
    Loading Diagram
    Bending Moment calculations for
    Segment 1:
    • Assuming the left end is constrained,
    maximum moment created by UDL for
    cantilever configuration is
    M1=wL2/2=-130.43*23002/2=-344987350N-
    mm(Here negative sign represents clockwise
    moment)
    • The value is approximated to 345e6N-mm.
    • Shear Force at location
    S1=wL=130.43*2300=300000N
    Shear Force Diagram for Segment 1
    Bending Moment Diagram for
    Segment1
    Shear Force for Segment 2:
    Bending Moment Diagram For
    Segment 2:
    Shear Force Diagram for Segment 3:
    Bending Moment Diagram for
    Segment 3:
    Shear Force Diagram For Full
    Structure:
    Bending Moment Diagrams For Full
    Structure:
    Pin Calculations
    • Pins are designed for shear load
    • Maximum shear load: F=300000N
    • Allowable stress τ =50N/mm2.
    • Since pin is in double shear, allowable shear for
    stress τ =25N/mm2
    • Area of the pin required
    • A=300000/25=12000mm2
    • Diameter of pin required d=62mm at the center
    Link Dimensions
    • Since two lifting links are used.
    • Load on each link : 300000/2= 150000 N
    • Minimum area required for the link
    A=150000/100 (100 is allowable stress)
    • Minimum area requirement for the link
    A=1500mm2.
    C-Frame Calculations
    • Minimum section required based on Bending Moment :
    • Maximum Bending Moment=345e6N-mm
    • Assuming a rectangular section of the beam
    • From basic mechanics of material formulations
    • σb= 6Mmax/(bh2)
    • here b=width of the beam
    • h=depth of the beam
    • due to 2 unknown variables width can be assumed.
    • width of the beam b=120mm
    • h2=6*345e6/(120* σb)=172500mm2
    • h=415mm.
    Analysis Results For The Given
    Dimensions
    Bending Stress Plot

    The figures shows structural safety for the design dimensions of 120mm width and
    428mm height for the beam. The segment 2 has maximum stress compared to the
    other regions. Since it is a heavy structure, self weight also plays very important role in
    the structural safety. So analysis is carried out further with self weight consideration. So
    further input of acceleration due to gravity and mass density are required as input to
    find the self weight solution.
    Self Weight Results – Deformation
    Plot
    Stress Due To Self Weight
    Total Self Weight
    Final Dimensions Considered
    • Due to the hole requirement for hinge at the
    center of plate , along with bush insertion the
    final dimensions are as follows.
    • Height of the beam : 800mm ( Due to removal of
    the material for hinging and bush placement)
    • Width of the beam: 120mm
    • Cross sectional area A=1e5mm2
    • Moment of Inertia of the problem: 0.54e10mm4.
    • Weight of the structure W=11973kg
    Final C-Frame Dimensions
    Three Dimensional View Of The
    Problem
    Mesh View Of The Problem

    Element Type : Solid45


    Number of element: 85872
    Number of nodes:62342
    Boundary Conditions
    Deformation Plot
    Vonmises Stress Plot
    Stress In The C-Frame
    Stress In Other Components
    Low Stress Regions
    Topology Optimized Structure

    By Element Birth and Death feature, the low stress elements can be killed
    and only live elements can be displayed using Ansys post processor. Final
    weight : 9773kgs. Overall weight reduction in the problem equal to 18%.
    Results And Discussions
    • Initially theoretical calculations are carried out for the given design
    requirements. Using free body diagram, initially bending moments and
    shear force diagrams are represented for the problem. Both theoretical
    and finite element calculations are compared and results found matching
    and so finite element calculations are carried out further.
    • Once the moments and shear forces are calculated , the sectional
    dimensions are calculated for structural safety. Due to the dimensional
    calculation, the design dimensions are altered and further iterations are
    carried out for structural safety under external loading and self weight.
    The final dimensions are concluded with width requirement of 120mm
    and height of the bema requirement of 800mm.
    • Further a three dimensional model is considered based on conventional
    rectangular representation with the calculated values. The geometry is
    built using Solid Edge software and meshed with Hypermesh. The results
    shows safety of the structure for the given structural loads(external load
    300000N, counter weight of 5 tons and self weight). But the results shows
    stress concentration on outer surfaces compared to the inner geometry.
    • topology optimisation is carried out to reduce the weight. The results
    shows weight reduction from 11973kgs to 9773kgs. So a weight reduction
    of 18% is observed in the problem.
    Further Scope
    • Composite material usage can be checked
    • Shape optimisation can be carried out
    • Transient response analysis can be carried out
    • Dynamic response can be calculated
    • Full assembly with coil in the position can be
    carried out
    • Possible thermal effects can be carried out
    References
    1. Vijendra Kumar, Badri Prasad,”Experimental Verification and Analysis of A U-
    Shaped Curved Beam Plate by using FEA Tool’, IJCSE, Vol 6, E-ISSN: 2347-2693,
    June 2018.
    2. Amaresh U, Rajashekhar Kuntanahal, “ Analysis and Design Optimisation of Multi
    Arm Lift”, IJRASET, ISSN: 2321-9653, Vol 5, Sep 2017.
    3. Shiv Pratap Singh Yadav, Kishan Reddy,” Numerical and Analytical Study on
    Curved Beams”, IJERT, ISSN: 2278-0181, Vol 6, April 2017.
    4. Eduardo Vazquez-Santacruz, “ Optimal Synthesis and 3D Modelling of a Lifting
    Mechanism for a Platform with Variable Slope”, Research in Computing Science
    107 pp 19-29,2015.
    5. Dr. P. Ravinder Reddy, K. B. Jagadeesh Gouda,”Analysis of Stress distribution in a
    Curved structure using Photoelastic and Finite element Method”, IOSR –JMCE”,
    ISSN: 2329-334x, pp 112-116,Issue 1, Ver III, 2015.
    6. Li Rong-hao, Yang Jue,” Optimisation Design of the Lifting Mechanism of the
    Electric Wheel Mining Truck”, JCPRCS, ISSN: 0975-7384, University of Science
    and Technology, Beijing. 2014.
    7. Sam Hutcheson,” Design and Construction of a portable Gantry Hoist”,
    California Polytechnic State University, 2013.
    8. A Sloboda, P. Honamandi,” Generalized Elasticity Method for Curved Beam
    Stress Analysis: Analytical and Numerical Comparisions for a Lifting Hook”,
    Mechanics based Design of Structures and Machines, Vol 35, issue 3, 2007.
    Thank You.

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