Fabrication Of Sheet Cutting Machine 5r1p1z

CHAPTER: 1 INTRODUCTION

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1.1 INTRODUCTION The sheet metal cutting process is a main part of the all industries. Cutting processes are those in which a piece of sheet metal is separated by applying a great enough force to cause the material to fail .Normally the sheet metal cutting machine is manually hand operated one for medium and small scale industries. The most common cutting processes are performed by applying a shear force, and are therefore sometimes referred to as shearing processes. Our project is about the implementation of hydraulic pressure in the process of cutting a metal sheet .Hence we introduce our project namely as “HYDRAULIC SHEET CUTTING MACHINE”. Automation in the modern world is inevitable. Any automatic machine aimed at the economical use of man either a machine or a material is worth the most. The sheet metal cutting machine works with the help of hydraulic cylinder. The piston is connected to the moving cutting tool. It is used to cut small sized pieces of the sheet metal. The machine is portable in size, so easily transportable. The hydraulic sheet cutting machine has a hydraulic cylinder piston attached to a sheet cutter which has 6mm thick blades, used to cut the required metal sheet into pieces .When the hydraulic jack is sealed and the lever arm is moved up and down, the pressure developed in the cylinder reservoir leads to the lifting of the piston rod which cause for the cutting tool to cut down the metal sheet.

The shearing is performed on a shear machine, often called squaring shear or power shear, that can be operated manually or by hydraulic, pneumatic, or electric power. A typical shear machine includes a table with arms to hold the sheet, stops or guides to secure the sheet, upper and lower straight - edge blades, a gauging device to precisely position the sheet.

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Fig: 1.1 Hydraulic sheet cutting machine The application of hydraulic to mechanical work helps for the reduction of human work force and helps in the increase in productivity by reducing time required. When the hydraulic jack is tightly air sealed, the fluid present in the hydraulic cylinder gets compressed. When the lever arm is continuously moved, the pressure is applied in the cylinder reservoir which leads to increase in internal pressure. Due to this, the piston rod moves upward which in turn moves the lever of the cutting machine. This lever moves in upward direction which causes the blade to cut it down.

1.2 TYPES OF SHEET CUTTING MACHINE There are various types of sheet cutting machine with respect to the type of operation applied on it. Sheet cutting machines are classified according to the following:1) Hydraulically operated 2) Pneumatically operated 3

3) Rack and pinion operated 4) Spring operated Brief descriptions of all the types are as follows: 1) Hydraulically operated:Here the lowering and raising of the header is carried over using the hydraulic piston and cylinder arrangement. To actuate the piston and cylinder, the oil is enters the cylinder from front or the back side of the piston. This hydraulic pressure causes for the cutting of even heavy weight objects with ease. The hydraulic operated has the most advantages than the other mentioned below. 2) Pneumatically operated:Here the advancement of the header is carried out in the upward and the downward direction using the pneumatic double acting piston and cylinder unit arrangement along with the foot operated direction control valve. In this type of machine high pressure air is used as the working fluid for the transfer of power and the motion 3) Rack and pinion operated:Here the lowering and the raising of the header are carried out manually using the rack and pinion arrangement. In this case the required pressure is applied manually using direct hand pressure on the rack using pinion and lever arrangement. Since the machine is robust and requires large pressure, hence it is not suitable. 4) Spring operated:The working of spring operated machine is similar to the rack and pinion operated machine but differs from it in construction. Here the lowering and the raising of the heating handle are carried out manually and it requires too much pressure for its operation and also there is possibility of having damage to the work piece if not handled carefully. Hence from the above described various types of sheet cutting machines , we can state that the hydraulic operated sheet cutting machine is more advantageous as it is light , portable, easy to handle and also has a very high cutting power than compared to all the other given various types of sheet cutting machines.

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1.3 PURPOSE Sheet cutting machine of hydraulic type is used to cut the sheets into two pieces by hydraulic power, there is no need of human effect for this machine This machine has bottom blade and top blade, where bottom blade is fixed one and top blade is moved by a hydraulic cylinder, remaining structures are made of forged steel and cutting blades are made of high carbon steel. The sheet metal cutting machine works with the help of hydraulic cylinder. The piston is connected to the moving cutting tool. It is used to cut small sized pieces of the sheet metal. The machine is portable in size, so easily transportable. The hydraulic sheet cutting machine has a hydraulic cylinder piston attached to a sheet cutter which has 6mm thick blades, used to cut the required metal sheet into pieces .When the hydraulic jack is sealed and the lever arm is moved up and down, the pressure developed in the cylinder reservoir leads to the lifting of the piston rod which cause for the cutting tool to cut down the metal sheet.

1.4 PROBLEMS The hydraulic sheet cutting machine has a hydraulic cylinder piston attached to a sheet cutter which has 6mm thick blades, used to cut the required metal sheet into pieces When the hydraulic jack is sealed and the lever arm is moved up and down, the pressure developed in the cylinder reservoir leads to the lifting of the piston rod which cause for the cutting tool to cut down the metal sheet. There are 2 major problems present in the hydraulic sheet cutting machine which have to be dealt to reduce loss of output and for safe working of machine. The first problem is the friction between the moving parts such as handle grooves and the upper knife grooves which causes the loss of motion in the sheet material. The second major problem is leakage of oil from hydraulic jack which causes for the jack to be replaced.

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CHAPTER: 2 PROBLEMS AND LITERATURE VIEW

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2.1 INTRODUCTION TO PROBLEMS AND LITERATURE VIEW Cutting processes are those in which a piece of sheet metal is separated by applying a great enough force to cause the material to fail. Most of the sheet metal cutting processes discussed can be performed on both sheet and plate metal, although for many sheet metal operations difficulties will arise with increasing plate thickness. Usually "sheet" and "sheet metal" is also referencing plate. The angle that the punch may be inclined varies from 4 to 15 degrees, however the higher the angle, the greater the magnitude of the horizontal force component acting to displace the work. For that reason angles are usually less than 9 degrees. Cutoffs and partings are important basic sheet metal cutting processes performed in manufacturing industry. Cutoffs need not be straight; rather they may be over several lines and/or curves. Partings are similar, in that a discrete part is cut from a sheet or strip of metal along a desired geometric path. The difference between a cutoff and a parting is that a cutoff can be nestled perfectly on the sheet metal, due to its geometry. With cutoffs, the cutting of sheet metal can be done over one path at a time and there is practically no waste of material. With partings, the shape cannot be nestled precisely. Partings involve cutting the sheet metal along two paths simultaneously. Partings waste a certain amount of material, which can be significant. 2.2 RECTIFICATION Every problem may have single solution or multiple number of solutions . Hence such a kind of a problem can also be rectified . the first problem of friction can be reduced by addition of lubrication and to fit them loosely so that they can reduce the friction caused by continuous movement .this helps in the reduction of motion loss in the machine the second problem of oil leakage can be rectified by making sure the seal, is locked and not broken .even if it is broken ,the seal can be removed and a new seal can be used. Make sure that the jack is not placed in inverted position as this causes the air to leak in and causing the jack to oil leakage.

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2.3 MERITS OF HYDRALIC SHEET CUTTING MACHINE: 1) Low cost 2) Less consumption of time 3) Easy to handle 4) Skilled labour is not required 5) Less maintenance 6) High accuracy 7) Good surface finish 8) Less floor space 2.4 DEMERITS OF HYDRAULIC SHEET CUTTING MACHINE: 1) Oil leakage 2) Reduces employment 3) Hard to refill is any loss.

2.5 Literature View The formation of any business begins with someone producing the initial idea for the project. The continued success of an established business depends upon the number and quality of the ideas fed intuits. Without a continual flow of new ideas, a business cannot function profitably or expand successfully and must, therefore eventually fade into total obscurity. Ideas for a new business project, a new product, a means of reducing manufacturing costs, or for solving industrial labor problems, begin in the human mind. Most people conceive their ideas unconsciously, and because they are unaware of the mental mechanics that caused the ’idea’ to be produced, they cannot repeat the ideation process to produce further profitable ideas at will. Fortunately, there are available established creative techniques which, when used correctly, do enable a person to produce a large number of first-class ideas at will. One such creative technique, and probably\ the most widely used in American industry, is ’brainstorming’.

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In shearing operation as the punch descends upon the metal, the pressure exerted by the punch first cause the plastic deformation of the metal. Since the clearance between the punch and the die is very small, the plastic deformation takes place in a localized area and the metal adjacent to the cutting edges of the punch and die edges becomes highly stressed, which causes the fracture to start on both sides of the sheet as the deformation progresses and the sheet is also sheared in the deformation process causing to cutting of the sheet.

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CHAPTER: 3 DESIGN

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3.1 EXPLANATION OF DESIGN The word design means different things to different people a wallpaper pattern a fashionable dress, the appearance of a racing car and so on. We therefore start by defining what we mean by design in the present context i.e. what design is all about? This understanding will lead to an examination of 1 Why we need to design particularly in an engineering environment, and 2 How we might best go about deg What is design? The Concise Oxford Dictionary explains design as a mental plan a scheme of attack, end in view, adaptation of means to ends preliminary sketch for picture invention Evidently there is a lot more to design than mere visual aspects, and design is not restricted to engineering. Key components of this explanation are as follows:1 Means to ends implies that we design not for the abstract mental exercise, but with a definite goal in view some action or some physical object will result from the design. 2 Mental suggests that design is a thinking process. 3 Plan, scheme infers that design is distinct from implementation. Designers especially in engineering seldom execute their plans, but rather communicate them to others either by word of mouth, or visually. Design is the application of creativity to planning the optimum solution of a given problem and the communication of that plan to others. Apart from the communication aspect therefore, we understand the essence of design to be problem solving, though the type of problem encountered in design is not like a typical textbook mathematics problem for example in which the unique correct solution is guaranteed by following, automaton-like, a series of learned solution steps. We expect that the design process, if properly carried out, will show a high probability of disclosing a solution which is optimum or close-to-optimum, if indeed a unique optimum exists. The prime aim of this chapter is to develop a structured approach to design an approach which will promote confidence in effectively solving real life 11

problems. We shall focus on problems involving engineering hardware particularly for Design and Build Competitions however the approach is perfectly general and applicable to problems arising from a marketing sortie or a labour wrangle for example. The approach is thus very relevant to managers and the like not just to ’hardware designers.

3.2 SHEARING As mentioned above, several cutting processes exist that utilize shearing force to cut sheet metal. However, the term “shearing” by itself refers to a specific cutting process that produces straight line cuts to separate a piece of sheet metal. Most commonly, shearing is used to cut a sheet parallel to an existing edge which is held square, but angled cuts can be made as well. For this reason, shearing is primarily used to cut sheet stock into amaller sizes in preparation for other processes. Shearing has the following capabilities Sheet thickness: 0.005 – 0.25 inches Tolerance: 0.1 inches The shearing is performed on a shear machine, often called asquaring shear or power shear, that can be operated manually or by hydraulic, pneumatic, or electric power. A typical shear machine includes a table with arms to hold the sheet, stops or guides to secure the sheet, upper and lower straight - edge blades, a gauging device to precisely position the sheet. The sheet is placed between the upper and the lower blade, which are then forced together against the sheet, cutting the material. In most devices, the lower blades remain stationary while the upper blade is forced downward. The upper blade is slightly offset from the lower blade, approximately 5 – 10% of the sheet thickness. Also the upper blade is usually angled so that the cut progresses from one end to the other, thus reducing the required force. The knife edge and are available in different materials, such as low alloy steel and high carbon steel.

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Fig: 3.1 shearing force acting on a metal sheet

3.3 SHEET METAL Sheet metal is simply a metal formed into thin and flat pieces. It is one of the fundamental forms used in metal working and can be cut and bent into a variety of different shapes. Countless everyday objects are constructed of the material. Thicknesses can vary significantly, although extremely thin thicknesses are considered foil or leaf, and pieces thicker than 6 mm (0.25 in) are considered plate. Sheet metal is available in flat pieces or as a coiled strip. The coils are formed by running a continuous sheet of metal through a roll slitter. The thickness of the sheet metal is called its gauge. Commonly used steel sheet metal ranges from 30 gauges to about 8 gauge. The larger the gauge number, the thinner the metal.

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Gauge is measured in ferrous (iron based) metals while nonferrous metals such as aluminium or copper are designated differently; i.e., Copper is measured in thickness by Ounce. There are many different metals that can be made into sheet metal, such as aluminium, brass, copper, steel, tin, nickel and titanium. For decorative uses, important sheet metals include silver, gold and platinum (platinum sheet metal is also utilized as a catalyst.) Sheet metal also has applications in car bodies, airplane wings, medical tables, roofs for buildings (Architectural) and many other things. Sheet metal of iron and other materials with high magnetic permeability, also known as laminated steel cores, has applications in transformers and electric machines. Historically, an important use of sheet metal was in plate armour worn by cavalry, and sheet metal continues to have many decorative uses, including in horse tack. Sheet metal workers are also known as "Tin Bashers",("Tin Knockers") which is derived from the hammering of seams when installing tin roofs.

3.4 SHEARED EDGE A variety of cutting processes that utilize shearing forces exist to separate or remove material from a piece of sheet stock in different ways. Each process is capable of forming a specific type of cut, some with an open path to separate portion of material and some with a closed path to cut out and remove that material. By using many of these processes together, sheet metal parts can be fabricated with cut outs and profiles of any 2D geometry. Such cutting process include the following 1. Shearing – Separating material into two parts 2. Blanking – Removing material to use for parts 3. Conventional blanking 4. Fine blanking 5. Punching – Removing material as scrap 6. Piercing 7. Slotting 8. Perforating 9. Notching 10. Nibbling 11. Lancing 12. Slitting 13. Parting 14

14. Cut-off 15. Trimming 16. Shaving 17. Dinking

Fig: 3.2 Different stages of metal shearing

3.5 COMPONENTS 1) Blades: - The blades area also called as knives. They are the very important parts of the sheet cutting machine which helps in the process of cutting the sheet in various small pieces 2) Gear:- The gear is a small attachment present to the handle and the upper knife to transmit the motion from handle to the upper knife 3) Frame: - The frame is the main part connecting the all the parts and causing the sheet cutting to take place. 15

Hydraulic jack: -A hydraulic jack is a mechanical device used as a lifting device to lift heavy loads or apply great forces Sheet cutting machine of hydraulic type is used to cut the sheets into two pieces by hydraulic power, there is no need of human effect for this machine This machine has bottom blade and top blade, where bottom blade is fixed one and top blade is moved by a hydraulic cylinder , remaining structures are made of forged steel and cutting blades are made of high carbon steel. The sheet metal cutting machine works with the help of hydraulic cylinder. The piston is connected to the moving cutting tool. It is used to cut small sized pieces of the sheet metal. The machine is portable in size, so easily transportable. The hydraulic sheet cutting machine has a hydraulic cylinder piston attached to a sheet cutter which has 6mm thick blades, used to cut the required metal sheet into pieces .When the hydraulic jack is sealed and the lever arm is moved up and down, the pressure developed in the cylinder reservoir leads to the lifting of the piston rod which cause for the cutting tool to cut down the metal sheet.

3.6 COST ESTIMATION 3.6.1 INTRODUCTION Cost estimation may be defined as the process of forecasting the expenses that must be incurred to manufacture a product. These expenses take into a consideration all expenditure involved in a design and manufacturing with all related services facilities such as pattern making, tool, making as well as a portion of the general istrative and selling costs. 3.6.2 PURPOSE OF COST ESTIMATING 1. To determine the selling price of a product for a quotation or contract so as to ensure a reasonable profit to the company. 2. Check the quotation supplied by vendors. 3. Determine the most economical process or material to manufacture the product.

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4. To determine standards of production performance that may be used to control the cost

3.7 TYPES OF COST ESTIMATION 1. Material cost 2. Machining cost 3. Labour cost 3.7.1 MATERIAL COST ESTIMATION Material cost estimation gives the total amount required to collect the raw material which has to be processed or fabricated to desired size and functioning of the components. These materials are divided into two categories:1. Material for fabrication: In this the material in obtained in raw condition and is manufactured or processed to finished size for proper functioning of the component. 2. Standard purchased parts: This includes the parts which was readily available in the market like Allen screws etc. A list in for chard by the estimation stating the quality, size and standard parts, the weight of raw material and cost per kg for the fabricated parts. 3.7.2 CALCULATION OF MATERIAL COST The general procedure for calculation of material cost estimation is 1. After deg a project a bill of material is prepared which is divided into two categories. a. Fabricated components b. Standard purchased components 2. The rates of all standard items are taken and added up. 3. Cost of raw material purchased taken and added up. 17

3.7.3 MACHINING COST ESTIMATION This cost estimation is an attempt to forecast the total expenses that may include manufacturing apart from material cost. Cost estimation of manufactured parts can be considered as judgment on and after careful consideration which includes lab our, material and factory services required to produce the required

Table: 3.1 Machining cost

3.7.4 LABOUR COST It is the cost of remuneration (wages, salaries, commission, bonus etc.) of the employees of a concern or enterprise. This cost can be reduced by 25%, if this machine is manufactured on mass quantity 18

Labor cost is classifies as: 1. Direct labor cost 2. Indirect labor cost Direct labor cost: The direct labor cost is the cost of labor that can be indentified directly with the manufacture of the product and allocated to cost centers or cost units. The direct labor is one, who counters the direct material into saleable product, the wages etc. of such employees constitute direct labor cost. Direct labor cost may be apportioned to the unit cost of job or either on the basis of time spend by a worker on the job or as a price for some physical measurement of product.

Indirect labor cost: It is that labor cost which cannot be allocated but which can be apportioned to or absorbed by cost centers or cost units. This is the cost of labor that doesn’t alters the construction, confirmation, composition or condition of direct material but is necessary for the progressive movement and handling of product to the point of dispatch e.g. maintenance, men, helpers, machine setters, supervisors and foremen etc. The total labor cost is calculated on the basis of wages paid to the labor for 8hours per day. Total Cost estimation is done as under Cost of project = (A) material cost + (B) Machining cost + (C) labor cost (A) Material cost is calculated as under:i) Raw material cost ii) Finished product cost

i) Raw material cost:It includes the material in the form of the Material supplied by the Steel authority of India limited as the round bars Channels, angles, square rods, plates along with the strip material form. We have to search for the suitable available material as per the requirement of designed safe values.

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Rate= 40/- per kg. Hence the cost of the raw material is as follows:Total of above = Rs 2155/ii) Finished product cost:Following the components which we have directly purchased from the Market, being easily available and cheaply availably available as compared to their manufacturing cost 1) Hydraulic cylinder = 1800/2) FML Unit = 6000/3) Welding rod = 120/4) Color (maroon, yellow, black, blue) = 200/5) Nuts& bolt (24) = 150/Total cost of the finished components = Rs 8270/iii) Labor cost:-

Table: 3.2 Labor cost

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Hence the total labor cost incurred = Rs. 1395/- From the above we can calculate the total manufacturing cost, i.e. Hence the total manufacturing cost = A ( i + ii ) + B + C = (2155 + 8270) + 1940 +1395 = Rs.3760/-

3.8 MACHINING TIME ESTIMATION This machining cost estimation gives us time require machining a particular component on machine. This gives us an estimation of how much time will be required to hire the machine for that particular component. This is done for all components except standard parts 3.8.1 PROCEDURE FOR CALCULATING MACHINING TIME 1) After the machining time has been calculated including allowance for each component because a component can have more than one operation to be carried out. Hence, rates of machine are different. 2) The machining time is calculated using standard working rates. 3) The time required to manufacture a given component on a machine is multiplied by machine rate to give machine cost. 4) The estimation of machining cost for total number of components gives us machining cost estimation. 5) Machining time of components are estimated in order to know total manufacturing cost of component. Total time includes basic time and various factors which are taken into consideration and they are:1) Up time and down time = 100% of basic Transportation time = 10 min Centrime time = 20 min 21

Inspection time = 20 min Other allowances taken into consideration are:1) Personal allowance = 5% of basic time 2) Fatigue allowance = 7% of basic time 3) Contingency allowance = 5% of basic time 3.8.2 TIME ANALYSIS A) Turning Operation The machining time in a lather work can be calculated for particular operation. If speed of job food and length of job is known as J.C. Then, Time taken for complete cut = 1 min = s x n Where, s = feed per revolution n = No. of revolution / min of job l = Length of job to be m/ced B) Shaping operation If length of cutting stokes, breadth of job feed and cutting speed are known time required to complete job may be calculated as T = L X B (1 + m)/1000 R V x S. Where, T = Total time taken to complete cut. L = length of stoke in mm R = the ratio of return time to cutting time V = the cutting speed expressed in m/min

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S = Feed expressed in mm/per double stroke C) Milling operation Time required to mill any component surface can be given as, T = A/sz x z x n Where, T = Time required to complete cut in min L = Length of table travel to complete cut in mm SZ = Feed per tooth in mm Z = No. of teeth of cutter n = No. of revolutions of cutter per minute D) Drilling operation Machining time in drilling operation can be determined by formula. T = 1/sr x n mm. Where, T = Machining time in min. .l = Length of travel of drill per min. .n = No. of revolutions of drill in mm. 3.8.3 TIME REQUIRED FOR MACHINING TIME COMPONENTS 1) Frame Angle measuring = 30 min Angle cutting = 45 min Welding = 120 min Total time = 195 min 2) Linkage 23

Measurement = 15 min Cutting = 15 min + 10 min = 25 min Drilling = 20 min Welding = 10 min 3) Hydraulic cylinder Facing = 20 min Turning = 25 min Drilling = 10 min + 20 min = 30 min Boring = 20 min Total time = 95 min 4) Casing Cutting = 120 min Bending = 40 min Drilling = 30 min Riveting = 25 min Total time = 115 min 5) Slots Cutting = 15 min Milling = 180 min Boring = 15 min Total time = 210 min 6) Rest plates Cutting = 15 min 24

Bending = 10 min Welding = 25 min Total time = 50 min

3.9 MATERIALS 3.9.1 MILD STEEL The three most common steel grades available in sheet metal are 304, 316, and 410. 

Grade 304 is the most common of the three grades. It offers good corrosion resistance while maintaining formability and weld ability. Available finishes are #2B, #3, and #4. Note that grade 303 is not available in sheet form.

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Grade 316 offers more corrosion resistance and strength at elevated temperatures than 304. It is commonly used for pumps, valves, chemical equipment, and marine applications. Available finishes are #2B, #3, and #4.

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Grade 410 is a heat treatable stainless steel, but does not offer as good corrosion resistance. It is commonly used in cutlery. The only available finish is dull.

Fig: 3.3 Microstructure of Steel

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3.9.2 PROPOSED WORK To prepare any machine part, the type of material should be properly selected, considering design, safety and following points:The selection of material for engineering application is given by the following Factors:1) Availability of materials. 2) Suitability of the material for the required components. 3) Suitability of the material for the desired working conditions. 4) Cost of the materials.

In addition to the above factors the other properties to be considered while selecting the material are as follows:Physical properties:These properties are color, shape, density, thermal conductivity, electrical conductivity, melting point etc. Mechanical properties:The properties are associated with the ability of the material to resist the mechanical forces and load. The various properties are:i) Strength: It is the property of material due to which it can resist the external forces without breaking or yielding. ii) Stiffness: It is the ability of material to withstand the deformation under stress. iii) Ductility: -It is the property of material due to which it can be drawn into wires under tensile load. iv) Malleability: It is the property of material which enables it to be rolled into sheets.

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v) Toughness: - It is the property of a material to bear the load acting on it. vi) Brittleness: It is the property of material due to which it breaks into pieces with little deformation. vii) Hardness: It is the property of material to resist wear, deformation and the ability to cut another material. viii) Resilience: It is the ability of the material to store energy and resist the shock and impact loads. ix) Creep: It is the slow and permanent deformation induced in a part subjected to a constant stress at high temperature. We have selected the material considering the above factors and also as per the availability of the material.

The materials which cover most of the above properties are:MILD STEEL Why steel, in particular? Simply because, in my humble opinion, it is the greatest material mankind has for construction. It is cheap, strong, readily available, easily cut, ed, and formed. Wood can be light and stiff, but not very strong. The best aluminum is strong and light, but very difficult to . Titanium is superb in of strength to weight ratio and stiffness but its incredibly expensive, difficult to obtain, and even more difficult and expensive to machine properly. There is no way you’re ever going to perform a battery-weld field-fix on a part made from 7075-T6 aluminum or titanium! In the end we come back to steel from mild carbon to some of the more exotic alloy steels pound for pound it is the most righteous material available for our needs. Where does steel come from? Steel is not a naturally occurring substance - it is entirely man made.

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Steel is chiefly a combination of two naturally occurring elements: iron and carbon (along with small amounts of other elements - depending on the steel in question). The process, by which man makes steel, would again fill several volumes. Here is my amateur synopsis:

Iron is mined from the ground in the form if a reddish-brown rock called iron-ore. This ore is then smashed up, strained, filtered, chemically treated etc, until ultimately it is melted in huge blast furnaces into something called pig iron. The process uses coke (a type of coal), which in turn imparts large amounts of carbon to the pig iron. As a result, pig iron itself is full of impurities, brittle, and unmachinable - practically useless. Except - it is the raw material from which all other irons and steels are made. Pig iron is so produced in either huge vats of molten material, or it is cast into ingots (in fact, pig iron got its name because the ingots or “chunks” produced were thought to have resembled piglets). Pig iron is then refined into either metallic iron or steel using specialized furnaces and processes. The distinction between the two is that metallic iron has between 2-6 A final word about carbon. Carbon is critically important to our whole discussion because it is the presence of carbon that turns the element of iron that is naturally soft and weak, into the strong, rigid materials we know as iron and steel. Precisely how this is so is beyond the scope of this article, suffice to say. The strength, hardness and toughness that make the ferrous based metals useful to us are profoundly influenced by the remarkable sensitivity of the physical and chemical properties of iron crystals to relatively small percentages of carbon dissolved within their matrixes (actually, the sensitivity is to the movement of dislocations within the crystal space lattice). This sensitivity to dissolved carbon is in fact, the very basis of ferrous metallurgy.

3.10 MACHINE CONSTRUCTION The machine is basically made up of mild steel. Reasons:

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1. Mild steel is readily available in market 2. It is economical to use 3. It is available in standard sizes 4. It has good mechanical properties i.e. it is easily machinable 5. It has moderate factor of safety, because factor of safety results in unnecessary wastage of material and heavy selection. 6. Low factor of safety results in unnecessary risk of failure 7. It has high tensile strength 8. Low co-efficient of thermal expansion Properties of Mild Steel: M.S. has carbon content from 0.15

BRIGHT MATERIAL: It is a machine drawned. The main basic difference between mild steel and bright metal is that mild steel plates and bars are forged in the forging machine by means is not forged. But the materials are drawn from the dies in the plastic state. Therefore the material has good surface finish than mild steel and has no carbon deposits on its surface for extrusion and formation of engineering materials thus giving them a good surface finish and though retaining their metallic properties A poor, but perhaps useful metaphor may be the use of fibre-mat and resin in fibre glass work. The bulk raw material of fibreglass is the fibre matting (as iron is to steel) - but by itself the matting is of no practical use. Not until we add the resin to it to make fibre glass (as we add carbon to iron to make steel) Do we get a useful product? In both cases, neither raw material is much use alone, but combines them nor do we really have something. Similarly, though carbon may only be present in small quantities, Justas the amount of hardener added to fibre glass resin has a profound effect on the material, so does the small amount of carbon present in useful metallic iron and steel 29

Composition: Carbon 0.20 Properties: Tensile strength 44.54 kgf/mm Yield stress: 28 kgf/mm Hardness: 170 BHN Uses: General purpose steels for low stressed components

Table: 3.3 Properties of Materials

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3.11 SPECIFICATIONS Hydraulic jack: - capacity

-3 ton

Minimum height

-195 mm

Lift height

-125 mm

Adjustment height

- 60 mm

Maximum height

-380 mm

Net weight

- 3.5 kgs

Sheet cutter:-Upper blade length

-240 mm

Lower blade length

-240 mm

Thickness of blades

-12 mm

Weight of cutting machine:

- 13.5 kgs

Width of sheet to cut:

- 0.005 to 0.05 mm

3.12 CALCULATIONS Cylinder specification: Bore diameter = 76 mm Wall thickness = 2.84 mm Length = 186 mm Piston thickness = 27 mm Pump specification: Max. Pressure = 175x105 N/m2 Force calculation: Area, A = Pi x r2 =4.53x10-3 m2 Force or load = P x A = 175x105x4.53x10-3 =79.275 kN Time taken to cut the sheet = 5.28 sec

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CHAPTER: 4 FABRICATION AND EXECTUION OF HYDRAULIC SHEET CUTTING MACHINE

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4.1 FABRICATION OF HYDRAULIC SHEET CUTTING MACHINE The sheet cutting machine is a main part of the all industries. Cutting processes are those in which a piece of sheet metal is separated by applying a great enough force to cause the material to fail. The hydraulic sheet metal cutting machine works with the help of hydraulic cylinder. The piston is connected to the moving cutting tool. It is used to cut small sized pieces of the sheet metal. The machine is portable in size, so easily transportable. The hydraulic sheet cutting machine has a hydraulic cylinder piston attached to a sheet cutter which has 6mm thick blades, used to cut the required metal sheet into pieces .When the hydraulic jack is sealed and the lever arm is moved up and down, the pressure developed in the cylinder reservoir leads to the lifting of the piston rod which cause for the cutting tool to cut down the metal sheet. The application of hydraulic to mechanical work helps for the reduction of human work force and helps in the increase in productivity by reducing time required. When the hydraulic jack is tightly air sealed, the fluid present in the hydraulic cylinder gets compressed. When the lever arm is continuously moved, the pressure is applied in the cylinder reservoir which leads to increase in internal pressure. Due to this, the piston rod moves upward which in turn moves the lever of the cutting machine. This lever moves in upward direction which causes the blade to cut it down

4.2 PARTS PRESENT IN SHEET CUTTING MACHINE The hydraulic sheet cutting machine consists of various parts which help in the cutting of the sheet material into various small pieces. The sheet cutting machine is attached to a hydraulic jack who in turn helps the machine to move very easily without any excessive force to add onto the sheet metal. The sheet cutting machine mainly consists of parts such as:-

1) Blades: - The blades area also called as knives. They are the very important parts of the sheet cutting machine which helps in the process of cutting the sheet in various small pieces

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Fig: 4.1 Blades The upper knife is attached to a handle which helps the gear to move both upward and down ward direction. The upper knife has a 2 bolts attached to it in either side which helps in its movement as we can see in the pic , the bolt on the left acts as a fulcrum attached to the frame where as the on the right helps for the motion transfer of the handle to the blade. The lower knife is a stationary knife which remains constant attached permanently to the frame as it has no respective use. The lower knife has a very sharp edge, same as the upper knife where the both knives meet causing for the sheet to get cut. There is a small gap of around 0.001 between both knives when they meet as to get a perfect cut of the metal sheet

2) Gear: - The gear is a small attachment present to the handle and the upper knife to transmit the motion from handle to the upper knife. It is not a complete gear but only the grooves of the gear which help on the transmission of motion.

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Fig: 4.2 Gear grooves

3) Frame: - The frame is the main part connecting the all the parts and causing the sheet cutting to take place. The frame is made out of mild steel as it requires a lot strength to hold the motion caused by the machine to hold it together. The frame is attached to the base and holds both the lower and upper knife together. It also holds the hydraulic jack to the machine to get the required motion to take place

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Fig: 4.3 Frame

4) Hydraulic jack: - The hydraulic jack is attached to the handle of the sheet cutting machine. When the air lock is sealed and lever of the jack is pushed up and down the ram piston is forced out or upwards as the main cylinder fills with pressurized fluid. This causes the handle to move down causing for the upper knife to move and cut the sheet. After the jack has done its job the release valve is opened and the fluid is ported back into the reservoir so the jacking cycle can be repeated.

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Fig 4.4 Hydraulic jack Comparing the hydraulic sheet cutting machine with ordinary sheet cutting machine There is a lot of variance between ordinary sheet cutter and hydraulic sheet cutting machine The hydraulic sheet cutting machine is far better and easy to operate than compared to ordinary sheet cutting machine as the hydraulic jack ceases to produce a lift of 3 tons causing the sheet cutting machine to cut more sheet of more thickness than compared to that of ordinary sheet cutting machine .It also reduces the human force as it is easy to operate the hydraulic jack than compared to other shearing machine as all the force applied on it is produced by a single jack which is operated very easily

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CHAPTER: 5 CONCLUSION

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CONCLUSION Now we know that hydraulic Sheet cutting machine is very cheap as compared to other sheet cutting machine. The range of the cutting thickness can be increased by applying pressure on hydraulic jack. This machine is advantageous to small sheet metal cutting industries as they do not have rely on the expensive Pneumatic shearing machine This project has met its objective to produce a Hydraulic sheet cutting machine and its function is to cut metal sheet of various width. We designed a hydraulic sheet cutting machine which costs less than that available in the market. We are very good at what we have done and had fun doing it. Our hydraulic sheet cutting machine is useful to cut metal sheet thicker than the capacity of the ordinary shearing machine as it is has 3 ton capacity jack. We can do simple operations like cutting and piercing, which is very useful and helpful to do small works at our college. We chose a simple frame which occupies less space which any one can operate, and manufactured it at 1/3rd of the original cost in the market. We tested our project by producing small bits and stripes of sheet metal.. As our project is based on manufacturing of hydraulic press and shearing machine, further modifications can be done to increase its applications.

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CHAPTER: 6 FUTURE SCOPE

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FUTURE SCOPE We engineers have the ability to think and plan. But due to some time constraints, we only have thought and put in the report, the following future modifications:1) It can be made pneumatic operated type by replacing the hand lever by pneumatic cylinder and air compressor. 2) The place where there is low atmospheric pressure, the hydraulic jack can be replaced by an I.C. Engine installed mechanism. Thus in future there are so many modifications, which we can make to survive the huge global world of competition.

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REFERENCES [1]. Anthony Esposito (2012) “Fluid Power” Pearson, ISBN 978-81-775-8580-3 [2]. Dr. R.K. Bansal (2010) “Fluid Mechanics and Hydraulic Machines” Laxmi Publications, ISBN 978-81-318-0815-3 [3]. Dr. R.K. Rajput (2006) “Strength of Materials” S.Chand, ISBN 81-219-2594-0 [4]. PSG College of Technology “PSG Design Data Book”(2012) [5]. T.J. Prabhu (2011) “Design of Transmission Element” [6]. V.B. Bhandari (2012) “Design of Machine Elements” Mc Graw Hill, ISBN 978-0-07068179-8 [7]. Vanalkar.A.V. Mechanism Synthesis for Stirrup Making Machine, Proceeding, 4th International Conference on Mechanical Engineering, ICME2001, BUET, Dhaka, BANGLADESH, pp. 271, December-2001 [8]. www.sciencedirect.com

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