IJIRST 窶的nternational Journal for Innovative Research in Science & Technology| Volume 1 | Issue 6 | November 2014 ISSN (online): 2349-6010
A Review on Topology Analysis and Optimization of Hydraulic Press Brake Saleha Shaikh ME Scholar Department Of Mech.Eng SAL College Of Engineering, Ahmedabad(India)
Hardik Bhatt Assistant Professor Department Of Mech.Eng SAL College Of Engineering, Ahmedabad(India)
Priyam Parikh Assistant Professor Department Of Mechatronics SAL College Of Engineering, Ahmedabad(India)
Abstract In the present review paper an effort is made to study the previous investigations that have been made in the different structural analysis and optimization techniques of hydraulic press brake. That analysis may be static or dynamic analysis. A no of analysis techniques like analytical and experimental are available for the structural analysis of hydraulic press brake. Same as no of optimization techniques are available for optimization of it like Taguchi method.. In this scenario, a structural optimization tool like topology optimization is becoming attractive in product design processes. Determination of the different structural or topology analysis and optimization through the various methods lie FEA, in a hydraulic press brake has been reported in literature. Keywords: FEA, ANSYS, Topology Optimization, Hydraulic Press Brake. _______________________________________________________________________________________________________
I. INTRODUCTION A press brake, also known as a brake press, is a machine tool for bending sheet and plate material, most commonly sheet metal. A typical press brake is a C-frame design with a moving ram, which hold punch and die located on a bed frame. It forms are predetermined bends by clamping the work piece between a matching punch and die.There are several types of brakes as described by the means of applying force: mechanical, pneumatic, hydraulic, and servo-electric. Hydraulic presses are operated by means of two synchronized hydraulic cylinders on the C-frames move the upper beam. Hydraulic operated press brakes are major types of press available since the inception of press brakes. A brake can be described by basic parameters, such as the force or tonnage and the working length.Additional parameters include the amplitude or stroke, the distance between the frame uprights or side housings, distance to the backgauge, and work height. The force exerted between the two beams is transferred through a frame (uses O-frames for their servo-electric press-brakes (figure 1). The beams and most other parts of the frame are generally built out of steel plates either welded or bolted together. [1]
Fig. 1: Frame Layout [1]
A typical hydraulic press brake normally consists of two or four posts or a column frame, a moving ram, hydraulic actuators, a bed frame, a back gauge set and a control unit. The motion of the ram includes down acting, up acting, and side acting, depending on its actuator configurations. The typical tonnage may vary from a few metric tons to over thousands while the working span may have a size more than eight to ten meters. In addition, the main tools of the press brakes include both punches
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A Review on Topology Analysis and Optimization of Hydraulic Press Brake (IJIRST/ Volume 1 / Issue 6 / 037)
and female dies. it is known that the punch which is held by the ram and the die on the bed frame play the key role in the process of sheet metal forming. A. Main components of hydraulic press brake:
Fig. 1:General layout of hydraulic press brake and its main component[1]
(1) (2) (3) (4) (5)
Machine frame: Structure of the machine. Table: Fixed part of the press brake that holds the die (here, the lower die) on a press brake. Ram: Mobile part of the alternating-movement press brake that holds the die (here, the upper die) on a press brake. Pressure actuator (cylinder): Actuator that uses hydraulic energy to move the ram. Digital control panel: (not illustrated) Human-machine interface that allows the operator to control the press brake (e.g., Load a bending program, adjust the speed of movement of the ram and the automatic positioning of the back gauges, etc.) (6) and (7) punch and Die: Tool consisting of an upper part and a lower part for bending pieces of metal. (8) Back gauge: Component, located behind the dies, that is used for depth positioning of the material to be bent. (9) Back gauge adjustment mechanism: Mechanism for adjusting the position of the back gauges. This mechanism can be manual or automatic. (10) Emergency stop button: (depending on the standard) Mushroom-shaped red button that, once depressed, Immediately initiates the emergency stop sequence. It must remain depressed until the operator releases it. Its resetting must not initiate a system restart. (11) Bending axis: Bending axis shown in fig are perpendicular to the sheet metal. (12) Material for bending (metal sheet): generally mild steel is used.[1] Structural analysis is a process to analyze a structural system to predict its responses and behaviors by using physical laws and mathematical equations. The main objective of structural analysis is to determine internal forces, stresses and deformations of structures under various load effects.[1] Structural design is a branch of Engineering that deals with systems comprised of a set of structural members. These members may be characterized as either truss or frame elements, connected by pinning or fixed joints. Structural optimization has become a valuable tool for engineers and designers in recent years. Structures are becoming lighter, stronger, and cheaper as the industry adopts higher forms of optimization. This type of problem solving and product improvement is now a crucial part of the design process in today’s engineering industry. The topic of optimization has its mathematical roots dating back to the 1670’s with the introduction of differential calculus.[4] Today, all the modern manufacturing enterprises are striving to develop better optimized reduced weight and cost effective products that meet the intended design, functionality and reliability. In this scenario, structural optimization tools like topology and shape optimization are becoming attractive in product design processes that we have studied in literature. Design upgradation is a company’s need to meet global competition. And Saving is very important in their future projects .So, thereby to reduce the weight of this machine and the manufacturing cost, and to enhance the performance of the machine topology optimization is a very important tool.[6] Structural optimization means determining the structure with the best objective given a set of constraints. The variables in the optimization are called design variables. Depending on what properties the design variables are described structural optimization can be divided into different subfields. In shape optimization the design variables are parameters which control the shape of part of the boundary of the structure. If the design variables are some sizing parameters like cross-section area, thickness of beams or plates we talk of size optimization. The most general subfield in structural optimization is topology optimization.[7]
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A Review on Topology Analysis and Optimization of Hydraulic Press Brake (IJIRST/ Volume 1 / Issue 6 / 037)
II. REVIEW OF WORK CARRIED OUT Pedro G. Coelhoaet.al.(2005)[2] conducted a study on structural analysis and optimization of hydraulic press brakes.It has been found that the source of deflection parallelism errors and minimize them through a structural optimization methodology. Based on the model of the bending process in press brakes defined by Timoshenko theory of beams, it has been not possible to design a machine that achieved uniform bending angles for every bending length because no optimal shapes or dimensions of the bed and ram that lead to parallel deflections for all bending lengths.Workpiece Bending errors have been derived by considering the influence of shape, dimensions and initial deformation of the machine structural components . Shape optimization, dimensional optimization has been performed to achieve uniform bending angles for every bending length. And optimal initial deformation was performed in decreasing the bending error. Work carried out by H.N.Chauhan and M.P.Bambhania(2013)[3] shows that, FE Analysis has been applied on a frame of 63 ton power press machine by Using Finite Element Method. Analysis of this frame is done by the simulation software. It is said that Instead of sharp corner of the c - frame, fillet is provided to reduce failure in the structure. Amount of fillet depends on load condition experienced by frame and it is analyzed by using FEM Tool. It is concluded that simulation software is the powerful tool for prediction of plate required for a given load.This analysis given the result of reduction in thickness of plate of frame structure, material saving and as well as cost benefits. B.Parthiban et.al.(2014)[4] conducted study on the design and analysis of C-type hydraulic press structure and cylinder. It represented C-type structure. Frame and cylinder are the main components of the hydraulic press. It is studied that the structural design of the frame depended on the pressing force this determined for the required rigidity, the dimensions of dies influencing the size of the tool area, work area accessibility that determined by the shape of the press frame. The performance of a hydraulic press depended on largely upon the behavior of its structure during operation. The analysis of hydraulic press structure is needed to increase their performance and productivity. The frame and cylinder are modeled by using modeling software CATIA. Structural analysis has been applied on c- frame by using analyzing software ANSYS. By using ANSYS software, structural performance and stress, strain distributions are plotted for verification. According to the structural values the dimensions of the frame and cylinder are modified to perform the functions satisfactorily as well as to reduce the weight for cost savings. S.M.Bapat and DessaiYusufali(2014)[5] have investigated on the design and optimization of a 30 ton hydraulic forming press machine. They have studied that analysis of the frame structure in terms of its material, geometry and stressed induced in it. Metal forming is one of the manufacturing processes which are almost chip less. In this paper the author focused on the causes of structural failure problem in the machine because hydraulic press continuously deals with the stress that may be compressive or tensile for that press machine always works under impact load condition. And because of impact load the hydraulic press always experienced continuous stress. It is studied that different components of the machine are subjected to different types of loading condition and are analyzed by using FEM tool ANSYS. Weight optimization of press frame and upper head is done, which in turn reduces in thickness of the frame structure and material. Work carried out by Muni Prabharan and V.Amarnath(2011)[6] shows that, topology optimization has been applied on various components of scrap baling press and 5 ton hydraulic press using ANSYS WORKBENCH software. Shape optimization is a promising tool to explore optimal solutions to engineering products. The benefits are numerous, including: load path visualization, weight savings, systems design space, ballistic protection and improved fatigue resistance.It is inferred that topology optimization results in a better and innovative product design. Sutasn Thipprakmas et.al.(2011) [7] conducted a study of the process parameter design of spring-back and spring-go into Vbending process using Taguchi technique.It is studied that, the process parameter of bending angle, material thickness and punch radius are very important to achieve a high precision of bent parts of complex shapes. The combination of the FEM simulation, the TAGUCHI method, and the ANOVA technique was an effective tool to predict the degree of importance of the process parameters in the v-bending process, in addition to aiding in the improvement of the quality of the required bending angle by optimization of the process parameters relating to the spring-back and spring-go. III.
CONCLUDING REMARKS
In this paper an effort is made to review the previous investigations that have been made on the analysis of various frame structures of press and hydraulic press brake machine. An attempt has been made in the present article to give an overview of various techniques developed for the analysis and optimization of frames and the results of it due to which further study on the frame will become easy.This literature survey gives the knowledge of shape optimization to reduce weight of the frame for topology optimization. And permits the analysis of existing press brake design solutions for optimizations of their performance and development of new solutions.The proposed design process successfully incorporates machining cost into a structural shape optimization problem. In addition to ensuring manufacturability of the structurally optimized components, the design process delivers components with minimum cost and required performance.
REFERENCES [1] [2]
Jasper Simons, Master’s Thesis, “Redesign Of A Press Brake”, Technische Universiteit Eindhoven, August 2006. Pedro G. Coelhoa, Luis O. Fariab, Joao B. Cardosoa(2005) “Structural Analysis And Optimization Of Press Brakes”, International Journal Of Machine Tools & Manufacture ,Vol45,Pp 1451–1460.
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A Review on Topology Analysis and Optimization of Hydraulic Press Brake (IJIRST/ Volume 1 / Issue 6 / 037) [3] [4] [5] [6] [7]
H.N.Chauhan And M.P.Bambhania(2013) “Design & Analysis Of Frame Of 63 Ton Power Press Machine By Using Finite Element Method”,Indian Journal Of Applied Research, Vol 3, Pp 285-288. B. Parthiban, P. Eazhumali, S.Karthi, P.Kalimuthu(2014) “Design And Analysis Of C Type Hydraulic Press Structure And Cylinder”, International Journal Of Research In Aeronautical And Mechanical Engineering, Vol 2,Pp47-56. S.M. Bapat And DessaiYusufali(2014|) “Design And Optimization Of A 30 Ton Hydraulic Forming Press Machine”, International Journal For Research In Applied Science And Engineering Technology, Vol 10, Pp 637-645. Muni Prabaharan And V.Amarnath(2011) “Structural Optimization Of 5ton Hydraulic Press And Scrap Baling Press For Cost Reduction By Topology”, International Journal Of Modeling And Optimization, Vol 1, Pp 185-190. Sultan Thipprakmas, Wiriyakorn Phanitwong (2011) “Process parameter design of spring-back and spring-go in V-bending process using the Taguchi technique”, Materials and Design, Vol 32, Pp 4430-4436
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