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DESIGN AND FABRICATION OF ROLLING MACHINE WITH SPLINES A dissertation submitted in partial fulfillment for the award of the degree of BACHELOR OF ENGINEERING in MECHANICAL ENGINEERING Submitted by ABDUL SALAM.A 92509144001 KADER BATCHA.A 92509144021 Under the Guidance of Asst. Prof. D. PALANISAMY M.E DEPARTMENT OF MECHANICAL ENGINEERING ANNA UNIVERSITY OF TECHNOLOGY TIRUCHIRAPPALLI TIRUCHIRAPPALLI – 620 024 April-2012 1 M.A.R. COLLEGE OF ENGINEERING AND TECHNOLOGY Viralimalai - 621316 BONAFIDE CERTIFICATE This is to certify that this is the bonafide of DESIGN AND FABRICATION PROJECT carried out by ABDUL SALAM.A and KADAR BATCHA .A Reg. No 92509144001 & 92509144021 in VI semester/ III year during 2011 – 2012. HEAD OF THE DEPARTMENT INTERNAL GUIDE PROJECT CO – ORDINATOR Submitted for the university practical examination held on Internal Examiner External Examiner 2 3 4 ACKNOWLEDGEMENT First of all we thank our god for his Shower of blessings and his Divine help which enables us to complete the project successfully. We are extremely thankful to our parents for enlightening us by providing professional education and for their prayerful support that makes us to complete the project. We extend our sincere thanks to Alhaj Er. A. Mohamed Yunus B.E., M.Sc., (Engg.) Founder & Chairman, M.A.R College of Engineering and Technology, Viralimalai, for offering the means of attaining our most cherished goal and Environment We extend our deepest gratitude to Principal Dr A. Edgar Ruskin Frank Ph.D, M.A.R College of Engineering & Technology, Viralimalai for giving us permission to do the project work successfully, We are grateful to express our profound thanks to S.SOMASUNDARAM M.E, Head of Department, M.A.R College of Engineering & Technology, Viralimalai, who has been a source of encouragement and moral strength throughout our study period. It gives immense pleasure to extend my sincere and heartfelt gratitude to project guide Mr.D.PALANISAMY M.E, Assistant Professor for his untiring, valuable and timely suggestion in dispensable situation during the period of study. Also heartfelt thanks to our friends, Teaching and Non Teaching Staff members who helped us to finish the project work successfully. 5 TABLE OF CONTENTS CHAPTER NO. 1. TITLE PAGE NO ABSTRACT 6 LIST OF TABLE 7 LIST OF FIGURES 8 INTRODUCTION 1.1 . GENERAL 9 1.2 DEFINITIONS 10 1.3 TYPE OF ROLLING 12 1.3.1 Hot rolling 12 1.3.3 Cold rolling 13 1.4 TYPES OF ROLLING PROCESS 14 1.4.1 Roll bending 14 1.3.2 Roll forming 15 1.3.3 Flat rolling 15 1.3.4 Foil rolling 16 1.3.5 Ring rolling 17 1.3.6 Structural shape rolling 18 1.3.7 Controlled rolling 18 6 2. LITERATURE REVIEW 19 2.1 Forces and geometrical relationships in rolling 19 2.2 Terminology 24 2.3 Products 27 2.4 Rolls 28 2.5 Rolling mills 30 2.5.1 Modern Rolling Mill 30 2.6 DESIGN CALCULATION 31 2.6.1 Dimension Of The Rolling Components 31 2.7 Fabrication Of Rolling Machine 33 2.7.1 Machining Operations 34 2.8 FURTHER OPERATION 35 2.9 BILL OF MATERIALS 36 2.10 COST ESTIMATION 37 2.10.1 Material cost 37 2.10.2. Machining cost 38 2.10.3 Over heads 2.10.4 Total cost 3. CONCLUSION 4. REFERENCES 7 38 ABSTRACT Rolling is the process in which the metal and alloys are plastically deformed into semi-finished or finished condition, by passing these between circular or contoured rotating cylinder (rolls).the metals is drawn into the opening between the rolls by frictional force s between the metal and the roll surface. In deforming metal between rolls, the workpiece is subjected to high compressive force from the squeezing action of rolls. In metalworking rolling is a metal forming process in which metal stock is passed through a pair of rolls. Rolling is classified according to the temperature of the metal rolled. If the temperature of the metal is above its recrystallization temperature, then the process is termed as hot rolling. If the temperature of the metal is below its recrystallization temperature, the process is termed as cold rolling. In terms of usage, hot rolling processes more tonnage than any other manufacturing process and cold rolling processes the most tonnage out of all cold working processes. Project is based on the need for rolling the sheet metal with splines design This design and fabrication purpose of rolling and designing the sheet metal. OUR PROJECT HAVE THE FOLLOWING OBJECTIVES: This rolling machine is used to roll the sheet metals with splines and to improve the strength of the sheet metals. Rolling machine is device which used for rolling the sheet metal. The sheet metals can be easily rolled. Even an unskilled technician can use them,With these features, we sincerely hope that our project serve as a valuable project. Welcome the correction, comments based on our project. 8 LIST OF TABLE NO DESCRIPTION PAGE NO Table 1 Bill of materials 36 Table 2 Material cost 37 Table 3 Machining cost 38 9 LIST OF FIGURES N0 DESCRIPTION PAGE NO Fig 1 Rolling Machine 10 Fig 2 Process Of Rolling Machine 11 Fig 3 Rolled Strips. 11 Fig 4 A Coil Of Hot-Rolled Steel 12 Fig 5 Process Of Rolling 14 Fig 6 Roll Forming 15 Fig 7 A Schematic Of Ring Rolling 16 Fig 8 Cross-Sections Of Continuously Rolled Structural Shapes Showing The Change Induced By Each Rolling Mill. 18 10 1. INTRODUCTION 1.1. GENERAL Steel is initially produced in 20 cm thick slabs. Steel in this form is usually processed further before being sold to customers. This generally involves rolling it into thinner sheets (and sometimes forming it into tubes). This steel is now conveniently shaped, but is prone to rusting so for applications where it is exposed to the weather it is often galvanized (and sometimes painted as well) to prevent corrosion. Step 1 - Hot Rolling In the hot rolling process, slabs are reheated and fed into the rough rolling mill where it is reduced from 210mm to 25mm thickness. The thin sheets are then wound onto spools to make 'coils' of rolled steel. Step 2 - Cold Rolling Hot rolled coils are welded into continuous sheets, and the iron oxides that have formed in hot rolling removed with hydrochloric acid: Fe2O3⋅xH2O + 6HCl → 2FeCl3 + (x+3)H2O The sheets are then oiled to prevent further corrosion and rolled. This rolling further reduces the thickness of the sheets and gives them a smoother surface. Step 3 - Galvanising Hot alkali solutions are used to remove the remaining grease, then the steel is treated with acid to clean and etch the surface. The steel is repeatedly heated and cooled to strengthen it and then galvanised by dipping it in zinc. The steel can then be used as is for roofing, or further processed. 11 Step 4 - Paint Coating The steel is again cleaned and then coated with primer. Solvent in the primer is evaporated by a hot air jet and the paint baked on. Finish coat is then applied, baked and cured on top of the primer coating. Different grades of finishing paint are used for different applications. 1.2 DEFINITIONS Definition of Rolling : The process of plastically deforming metal by passing it between rolls. Rolling is the most widely used forming process, which provides high production and close control of final product. The metal is subjected to high compressive stresses as a result of the friction between the rolls and the Rolling process metal surface. SHEET METAL ROLLING MACHINE: fig 1 rolling MACHINE. The rolling machine without splines in various industries. 12 fig.2 process of rolling machine fig 3 rolled strips. Finished rolled sheet metals 13 1.3 TYPE OF ROLLING 1.3.1 Hot rolling Fig 4. A Coil of Hot-Rolled Steel Hot rolling is a metalworking process that occurs above the recrystallization temperature of the material. After the grains deform during processing, they recrystallize, which maintains an equiaxed microstructure and prevents the metal from work hardening. The starting material is usually large pieces of metal, like semi-finished casting products, such as slabs, blooms, and billets. If these products came from a continuous casting operation the products are usually fed directly into the rolling mills at the proper temperature. In smaller operations the material starts at room temperature and must be heated. This is done in a gas- or oil-fired soaking pit for larger work pieces and for smaller work pieces induction heating is used. As the material is worked the temperature must be monitored to make sure it remains above the recrystallization temperature. To maintain a safety factor a finishing temperature is defined above the recrystallization temperature; this is usually 50 to 100 °C (90 to 180 °F) above the recrystallization temperature. If the temperature does drop below this temperature the material must be re-heated before more hot rolling. Hot rolled metals generally have little directionality in their mechanical properties and deformation induced residual stresses. However, in certain instances non-metallic inclusions will impart some directionality and work pieces less than 20 mm (0.79 in) thick often have some directional properties. Also, non-uniformed cooling will induce a lot of residual stresses, which usually occurs in shapes that have a non-uniform cross-section, such as Ibeams and H-beams. While the finished product is of good quality, the surface is covered in mill scale, which is an oxide that forms at high-temperatures. It is usually removed via 14 pickling or the smooth clean surface process, which reveals a smooth surface. Dimensional tolerances are usually 2 to 5% of the overall dimension. Hot rolled mild steel seems to have a wider tolerance for amount of included carbon than cold rolled, making it a bit more problematic to use as a blacksmith. Also for similar metals, hot rolled seems to typically be more costly. Hot rolling is used mainly to produce sheet metal or simple cross sections, such as rail tracks. 1.3.2 Cold rolling Cold rolling occurs with the metal below its recrystallization temperature (usually at room temperature), which increases the strength via strain hardening up to 20%. It also improves the surface finish and holds tighter tolerances. Commonly cold-rolled products include sheets, strips, bars, and rods; these products are usually smaller than the same products that are hot rolled. Because of the smaller size of the work pieces and their greater strength, as compared to hot rolled stock, four-high or cluster mills are used. Cold rolling cannot reduce the thickness of a work piece as much as hot rolling in a single pass. Cold-rolled sheets and strips come in various conditions: full-hard, half-hard, quarter-hard, and skin-rolled. Full-hard rolling reduces the thickness by 50%, while the others involve less of a reduction. Skin-rolling, also known as a skin-pass, involves the least amount of reduction: 0.5-1%. It is used to produce a smooth surface, a uniform thickness, and reduce the yield point phenomenon (by preventing Lüders bands from forming in later processing). It locks dislocations at the surface and thereby reduces the possibility of formation of Lüders bands. To avoid the formation of Lüders bands it is necessary to create substantial density of unpinned dislocations in ferrite matrix. It is also used to breakup the spangles in galvanized steel. Skin-rolled stock is usually used in subsequent cold-working processes where good ductility is required. Other shapes can be cold-rolled if the cross-section is relatively uniform and the transverse dimension is relatively small. Cold rolling shapes requires a series of shaping operations, usually along the lines of sizing, breakdown, roughing, semi-roughing, semi-finishing, and finishing. 15 If processed by a blacksmith, the smoother, more consistent, and lower levels of carbon encapsulated in the steel makes it easier to process, but at the cost of being more expensive 1.3 TYPES OF ROLLING PROCESS : 1.3.1Roll bending fig 5. Roll bending Roll bending produces a cylindrical shaped product from plate or steel metal. 16 1.3.2 Roll forming fig 6. Roll forming Roll forming is a continuous bending operation in which a long strip of metal (typically coiled steel) is passed through consecutive sets of rolls, or stands, each performing only an incremental part of the bend, until the desired cross-section profile is obtained. Roll forming is ideal for producing parts with long lengths or in large quantities. There are mainly 3 main processes, 4 rollers, 3 rollers and 2 rollers, and have different advantages according to the specifications of the plate (thickness length and diameter) and the shapes. Also call roll bending or plate rolling process this is used in many fields, Exhaust pipes, Trucks brakes, Pressure Vessel Tanks Gaz tanks, Components for airbags, Fire extinguishers, Hot water boilers, Drawer rails, Filter housings, Fittings, Fuel filters, Gear components, Gear selector forks, Multi diameter Shells, Pressurized containers, Pumps' shells, Rear axles, Sink mountings, Spinning compatible tubes, Washing drumbs. 17 1.3.3 Flat rolling Flat rolling is the most basic form of rolling with the starting and ending material having a rectangular cross-section. The material is fed in between two rollers, called working rolls, that rotate in opposite directions. The gap between the two rolls is less than the thickness of the starting material, which causes it to deform. The decrease in material thickness causes the material to elongate. The friction at the interface between the material and the rolls causes the material to be pushed through. The amount of deformation possible in a single pass is limited by the friction between the rolls; if the change in thickness is too great the rolls just slip over the material and do not draw it in. The final product is either sheet or plate, with the former being less than 6 mm (0.24 in) thick and the latter greater than; however, heavy plates tend to be formed using a press, which is termed forming, rather than rolling.[ Oftentimes the rolls are heated to assist in the workability of the metal. Lubrication is often used to keep the workpiece from sticking to the rolls. To fine tune the process the speed of the rolls and the temperature of the rollers are adjusted. 1.3.4 Foil rolling Foil rolling is a specialized type of flat rolling, specifically used to produce foil, which is sheet metal with a thickness less than 200 µm (0.0079 in). The rolling is done in a cluster mill because the small thickness requires a small diameter rolls. To reduce the need for small rolls pack rolling is used, which rolls multiple sheets together to increase the effective starting thickness. As the foil sheets come through the rollers, they are trimmed and slitted with circular or razor-like knives. Trimming refers to the edges of the foil, while slitting involves cutting it into several sheets. Aluminum foil is the most commonly produced product via pack rolling. This is evident from the two different surface finishes; the shiny side is on the roll side and the dull side is against the other sheet of foil. 18 1.3.5 Ring rolling fig 7. A schematic of ring rolling Ring rolling is a specialized type of hot rolling that increases the diameter of a ring. The starting material is a thick-walled ring. This workpiece is placed between two rolls an idler roll, while another roll, called the driven roll, presses the ring from the outside. As the rolling occurs the wall thickness decreases as the diameter increases. The rolls may be shaped to form various cross-sectional shapes. The resulting grain structure is circumferential, which gives better mechanical properties. Diameters can be as large as 8 m (26 ft) and face heights as tall as 2 m (79 in). Common applications include rockets, turbines, airplanes, pipes, and pressure vessels. 19 1.3.6 Structural shape rolling fig 8. Cross-sections of continuously rolled structural shapes, showing the change induced by each rolling mill. 1.3.7 Controlled rolling Controlled rolling is a type of thermomechanical processing which integrates controlled deformation and heat treating. The heat which brings the workpiece above the recrystallization temperature is also used to perform the heat treatments so that any subsequent heat treating is unnecessary. Types of heat treatments include the production of a fine grain structure; controlling the nature, size, and distribution of various transformation products (such as ferrite, austenite, pearlite, bainite, and martensite in steel) inducing precipitation hardening and, controlling the toughness. In order to achieve the entire process must be closely monitored and controlled. Common variables in controlled rolling include the starting material composition and structure, deformation levels, temperatures at various stages, and cool-down conditions. The benefits of controlled rolling include better mechanical properties and energy savings. 20 2. LITERATURE REVIEW 2.1 Forces and geometrical relationships in rolling : • A metal sheet with a thickness ho enters the rolls at the entrance plane xx with a velocity vo. • It passes through the roll gap and leaves the exit plane yy with a reduced thickness hf and at a velocity vf. • Given that there is no increase in width, the vertical compression of the metal is translated into an elongation in the rolling direction. • Since there is no change in metal volume at a given point per unit time throughout the process, therefore bhovo = bhv = bhf vf …Eq.1 Where b is the width of the sheet v is the velocity at any thickness h intermediate between ho and hf. From Eq.1 Bhovo = bhf vf Given that bo = bf Ho 𝑳𝒐 𝒕 = hf 𝑳𝒇 𝒕 Then we have voho = vf hf 𝐯𝐨 𝐯𝐟 𝐡𝐟 = 𝐡𝐨…Eq.2 21 When ho > hf , we then have vo < vf The velocity of the sheet must steadily increase from entrance to exit such that a vertical elementin the sheet remain undistorted. • At only one point along the surface of contact between the roll and the sheet, two forces act on the metal: 1) a radial force Pr and 2) a tangential frictional force F. • If the surface velocity of the roll vr equal to the velocity of the sheet, this point is called neutral point or no-slip point. For example, point N. • Between the entrance plane (xx) and the neutral point the sheet is moving slower than the roll surface, and the tangential frictional force, F, act in the direction (see Fig) to draw the metal into the roll. • On the exit side (yy) of the neutral point, the sheet moves faster than the roll surface. The direction of the frictional fore is then reversed and 22 oppose the delivery of the sheet from the rolls. Pr is the radial force, with a vertical component P (rolling load - the load with which the rolls press against the metal). The specific roll pressure, p, is the rolling load divided by the contact area. 𝑃 P= 𝑏𝐿𝑝 …Eq.3 Where, b is the width of the sheet. Lp is the projected length of the arc of contact. 𝐿𝑝 = [𝑅(ho-hf)−(ho-hf) / 4]^1/2 = [R(ho-hf)]^2 …Eq.4 • The distribution of roll pressure along the arc of contact shows that the pressure rises to a maximum at the neutral point and then falls off. • The pressure distribution does not come to a sharp peak at the neutral point, which indicates that the neutral point is not really a line on the roll surface but an area. • The area under the curve is proportional to the rolling load. • The area in shade represents the force required to overcome frictional forces between the roll and the sheet. • The area under the dashed line AB represents the force required to deform the metal in plane homogeneous compression. 23 Simplified analysis of rolling load The main variables in rolling are: • The roll diameter. • The deformation resistance of the metal as influenced by metallurgy, temperature and strain rate. • The friction between the rolls and the workpiece. • The presence of the front tension and/or back tension in the plane of the sheet. We consider in three conditions: 1) No friction condition 2) Normal friction condition 3) Sticky friction condition. • Frictional force is needed to pull the metal into the rolls and responsible for a large portion of the rolling load. • High friction results in high rolling load, a steep friction hill and great tendency for edge cracking. 24 • The friction varies from point to point along the contact arc of the roll. However it is very difficult to measure this variation in μ, all theory of rolling are forced to assume a constant coefficient of friction. • For cold-rolling with lubricants, μ ~ 0.05 – 0.10. • For hot-rolling , μ ~ 0.2 up to sticky condition. Problems and defects in rolled products Defects from cast ingot before rolling • Porosity, cavity, blow hole occurred in the cast ingot will be closed up during the rolling process. • Longitudinal stringers of non-metallic inclusions or pearlite banding are related to melting and solidification practices. In severe cases, these defects can lead to laminations which drastically reduce the strength in the thickness direction. Defects other than cracks can result from defects introduced during the ingot stage of production. 25 under high rolling forces, the rolls flatten and bend, and the entire mill is elastically distorted. • Mill spring causes the thickness of the sheet exiting from the rolling mill to be greater than the roll gap set under no-load conditions. • Precise thickness rolling requires the elastic constant of the mill. Calibration curves are needed, see Fig. (1–3 GNm-1 for screw-loaded rolling mills, 4 GNm-1 for hydraulically loaded mills). 2.2 Terminology • Bloom is the product of first breakdown of ingot (cross sectional area > 230 cm2). • Billet is the product obtained from a further reduction by hot rolling (cross sectional area > 40x40 mm2). • Slab is the hot rolled ingot (cross sectional area > 100 cm2 and with a width ≥ 2 x thickness). Solutions to flatness problems • Camber and crown can be used to correct the roll deflection (at only one value of the roll force). Or use rolling mill equipped with hydraulic jacks to permit the elastic distortion of the rolls to correct deflection. 26 fig 8 process of rolling • Hot mill can be provided with facilities for crown control to improve the control of the profile of hot strip mill. • For example work roll bending with continuous variable crown and pair cross mills. •The roll cross angle of rolls incorporated in a stand of each rolling mill is set at a predetermined value beforehand. • If there is a roll cross angle that will enable a target sheet crown to be applied to each sheet and the roll bender load of each stand is adjusted on-line, thereby effecting sheet crown control. 27 Thickness measurement in continuous COLD STRIP MILLS fig. sensor rolling • Thickness is measured by x-ray gauges while the error in the thickness following the first tand is usually fedback to adjust the gap sitting on the first stand. • Gauge control in subsequent stands usually is achieved by controlling the strip tension through controlling the relative roll speed in successive stands or the coiler speed. • Gauge control through control of strip tension has faster response time than control through change in roll setting. 28 2.3 Products: • Plate is the product with a thickness > 6 mm. • Sheet is the product with a thickness < 6 mm and width > 600 mm. • Strip is the product with a thickness < 6 mm and width < 600 mm. Mill products Further rolling steps Bloom Billet Slap Plate Sheet Strip 29 2.4 ROLLS : 30 ROLLING WITH SPLINES 31 2.5 ROLLING MILLS 2.6.2 DESIGN PROCEDURE A rolling mill basically consists of 1. Rolls 2. Bearings 3. a housing for containing these parts 4. a drive (motor) for applying power to the rolls and controlling the speed. 32 2.5.1 MODERN ROLLING MILL : 1. Requires very rigid 2. Construction , large motors to supply enough power (MN). Successive stands of a large continuous mill 2.6 DESIGN CALCULATION 2.6.1 DIMENSION OF THE ROLLING COMPONENTS: 1. Length of hollow pipe = 300 mm 2. diameter of hollow pipe = 40 mm 3 MS – rod length = 300 mm 4. MS –rod diameter = 40 mm 6. Pipe rings thickness = 5 mm 33 2.6.2.1 SELECTION OF ROLLER A roller is to be selected for making a rolls the sheet metal is required diameter = 40 mm and length =300mm 2.6.2.2 SELECTION OF GEARS We can go for the spur gears for the three rollers to transmit the power to the rollers from the rotating handle. 34 FINISHED JOB Fig. FINISHED JOB 2.7 FABRICATION OF ROLLING MACHINE There are few types of fabrication methods are done on this rolling machine. They are, 1. Drilling 2. Turning 3. Grinding 4. Chamfering 5. Milling 6. Boring 7. Grooving 8. Welding 35 2.7.1 MACHINING OPERATIONS: Drilling Drilling is used to produce holes in objects. In this project the jig plates requires the holes for making bolted assembly. Also to fitting the bushes holes are required. These holes are done by conventional vertical type drilling machine. Fine grinding It is nothing but the grinding process, which is done as smooth with fine grains. This is done as the each plate and flanges for good surface finish. It is done by conventional grinding machine. Chamfering It is the process used to smooth the sharp edges. It is required in the fabrication processes in order to avoid scratches made by the parts. In this project it is used to smooth the sharp edges of the gas cutted plates. Welding It is the process, which is used to join two, is more similar materials as well as dissimilar materials. In this project it is used to join the round flanges with the l-bow pipe to make the work piece. This is done by arc welding machine. Boring Boring is the process which is used to make material removal internally. In this project it is used to boring on the two cover plates to hold the l-bow with flange. Through bores are also produced on the two cover plates. This is done by using lathe. 36 Milling Milling is used to machine curved surfaces. In this project the flanges for elbow pipe and supporting blocks need curved surfaces. This is done by using conventional milling machine. Grooving It is used in this project to make the groove on the both sides of top cover plate. This is done by conventional lathe. 2.8 FURTHER OPERATIONS Cleaning It is the operation to clean the all machined parts without burrs, dust and chip formals. By meaning the parts they are brightened and goodlooking. Assembling It is the operation, which deals with the assembling of various parts produced by above operations. 37 2.9 BILL OF MATERIALS Table 1 SNO PART NAME MATERIAL NO.OFF 1 Hollow pipe G.I 2 2 Rod Mild steel 1 3 Plate Mild steel 2 4 Spur gear Mild steel 3 5 shaft Mild steel 3 6 Sheet (raw material) Galvanized iron 1 2.10 COST ESTIMATION 2.10.1 MATERIAL COST: Table 2 S.NO COMPONENTS QUANTITY COST 1 Hollow pipe 2 RS.120 2 Rod 1 RS.150 3 Plate 2 RS.50 4 Spur gear 3 RS.350 5 Job 1 Rs.75 Rs. 745 Total 38 2.10.2 MACHINING COST: Table 3 S.NO MACHINING OPERATION COST 1 LATHE WORK Rs. 300 2 DRILL WORK Rs.125 3 MILLING WORK Rs.175 4 WELDING WORK Rs.150 5 GRINDING WORK Rs.125 TOTAL Rs.875 2.10.3 OVER HEADS: MACHINING COST = Rs.875 TRANSPORTATION COST = Rs. 200 ____________ TOTAL = Rs.1075 ____________ 39 2.10.4 TOTAL COST: Material cost = Rs.745 Overheads = Rs.1075 = Rs.1820 Total 2.11 Problems and defects in rolled products Defects from cast ingot before rolling • Porosity, cavity, blow hole occurred in the cast ingot will be closed up during the rolling process. • Longitudinal stringers of non-metallic inclusions or pearlite banding are related to melting and solidification practices. In severe cases, these defects can lead to laminations which drastically reduce the strength in the thickness direction. 40 3. CONCLUSION This report deals with the design and fabrication of Rolling machine and the detailed drawing of the component and assembles. The project carried out by us made an impressing task in forming process. It is very useful in sheet metal industries for mass production. 4. References: • Dieter, G.E., Mechanical metallurgy, 1988, SI metric edition, McGraw-Hill, ISBN 0-07-100406-8. • Edwards, L. and Endean, M., Manufacturing with materials, 1990, Butterworth Heinemann, ISBN 0-7506-2754-9. • Beddoes, J. and Bibbly M.J., Principles of metal manufacturing process, 1999, Arnold, ISBN 0-470-35241-8. • Lecture note, 2003. • Firth Rixson leavelets. • Metal forming processes, Prof Manas. • Metal forming lecture, Ass Prof. P. Srichareonchai. 41