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    Capacity Calculator for Rotary Draw Tube BendingVäxjö 2012-06-11Course Code: 2MT00EBachelor Degree ProjectSeda Köseoğlu,Hasan ParlakSupervisor: Lars EricssonExaminer: Izudin DugicSchool of Engineering

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    IOrganisation/OrganizationFörfattare/AuthorsLinnaeus University Seda KöseoğluSchool of EngineeringHasan ParlakDokumenttyp/Type of Document Handledare/tutor Examinator/examinerExamensarbete/Degree Project Lars Erics...

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    IIAbstractPlastic deformation of tubes can be achieved in numerous ways. One of the most useful typeis CNC tube bending machines which is used in many industries such as aerospace,automotive, HVAC systems and so on. It is important that all components of system shouldmate properly after producin...

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    IIIAcknowledgementFirst of all, we are extremely grateful for having the opportunity to have worked on this thesisproject. It was a gratifying feeling to have solved this real problem for Herber EngineeringAB before graduating from university. To see usage of our program in the industry is a prou...

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    IVTable of ContentAbstract.................................................................................................................................................. IIAcknowledgement .............................................................................................................

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    11 IntroductionOver the last decade bending technology has been a sensation in the field of engineeringbecause this area can be continually improved, resulting in higher quality with lesstroubleshooting and manufacturing defects. In this manner, Research and Development(R/D)departments provide ti...

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    21.2 PurposeThe main goal of this project is composition of plastic deformation in tube bending theory andthe effects of CNC bending machine parts including; wiper die, mandrel, booster andsupporter die to obtain optimum bending requirements. After realization of all parameters, aforms applicatio...

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    32 TheoryIn this chapter, the introduction of rotary draw bending is presented alongside machinery partswith their function and effects on bending moment and failure types along with their reasons.Also shown is plastic deformation in tube bending and the effect of tools’ parameters.2.1 Rotary D...

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    42.1.1 Machinery Parts And Their FunctionsThe fundamental steps of rotary draw tube bending operation can be described:The bend die assistant, clamp die and pressure die are parallel to the feeding existbefore the start of the bending operation.The clamp die presses the tube tightly against...

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    5Figure2.3 Cross-sectional view of bended tube on bend die(http://www.hinesbending.com/BASICTUBEBENDINGGUIDE.pdf)2.1.1.2 Function of Clamp DieThe clamp die works in conjunction with the bend die to ensure it clamps the tube to the benddie. The clamp die will move in and out to allow feeding of th...

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    62.1.1.3 Fuction of Support(Pressure) DieThe pressure die is used to press the tube into the bend die and to provide the reaction forcefor the bending moment. The pressure die will travel with the tube as it is being formed. Thepressure die boost cylinder is attached to the pressure die.(http://f...

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    72.1.1.5 Function of BoosterA pressure function found on some tube-bending machines which is similar to the commonassist-pressure function but is distinguished from it by applying pressure to both sides of thetube behind the line of tangency. Assist pressure is applied only to the outside half of...

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    82.1.3.1 Tube BreakageThere are several reason for breaking of tubes:Material lacking proper ductility and elongationTube slipping in clamp diePressure die too tight causing excess dragMaterial wrinkling and becoming locked between mandrel ballsClamp die pressing on mandrel balls...

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    92.2.1 NotationrAverage radius of the tube cross-sectionDOutside diameter of the tubedInside diameter of the tubekGeometry parameterRBending radius sMaterial yield strengthαAngle between circumferential point,center point and the topmost point in tube sectionIThe moment of inertiaJThe moment ...

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    10Figure2.7 Comprasion of derived and simplified bending moment function(N.C.Tang, 2000)According to Johansson(2010), section modulus ‘Wb’ is given by:=32( − )(5)After all these formulations, according to Tang(2000), bending moment is given by:=(6)2.2.3 Working Principle of Rotary Draw Bend...

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    11Figure 2.8 Representation of tools on CNC bending machineIt is also available for booster as well but the difference between pressure die and booster isdistance parameter on bending formula because booster affects on along center of the tube, itmeans bending axis. It means that:If pressure d...

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    12The friction between tube and wiper die approximately increases the normal bending momentof 25 to 200 % depending on lubrication or not. This affect can be shown as Mw. Same withthe mandrel approximately increases the normal bending moment 25 to 200 % depending onlubrication or not. This affect...

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    133 MethodFirstly, gathering of information to follow right way for this thesis was important beforemeeting with company. It was good to understand function and working principle of CNCrotary draw bending machine.After meeting with Herber Engineering AB, the problem was understood exactly with to...

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    14Figure3.1 Flowchart of form application programFinally, it was important to verify the results of program acceptable or not. There are twoways to understand this:Form application program has been used on Herber Engineering AB’s works and theirfeedback was positive because of theory and rea...

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    154 Results and DiscussionIn this project, the combination of theory of tube bending and tools effects of CNC rotarydraw bending was observed detailed. All these were created base of form applicationprogram algorithm. This program was also written by Microsoft Visual Studio 2010 with C++programm...

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    16Figure4.2 Results of example1 on form application program without factors of machineFigure4.2 Results of example2 on form application program without factors of machine

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    175 ConclusionIn the thesis, the rotary draw tube bending theory with all parameters performed on a formapplication program. This program was written by Microsoft Visual Studio 2010 with C++programming language.Tube bending is carried really big importance in most of industrial applications such ...

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    186 ReferencesBook&ArticlesTang,N.C, 2000, Plastic deformation analysis in tube bending, International Journal ofPressure Vessels and Piping 77 (2000) 751-759,Canada.Fuchs, F.J,Jr, Waveguide Bending Design Analysis, Manuscript receieved, June 4,1959,pp1457.Johansson, J, Automated Computer Sys...

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    19AppendixAppendix AFront Panel of the form application programHerber Dual 300/700 Bending Machine

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