1 Lecture slides on rolling By: Dr H N Dhakal Lecturer in Mechanical and Marine Engineering, School of Engineering, University of Plymouth
2 Bulk deformation forming (rolling) Rolling is the process of reducing the thickness (or changing the cross-section) of a long workpiece by compressive forces applied through a set of rolls. This is the most widely used metal working process because it lends itself high production and close control of the final product.
3 Bulk deformation forming (rolling)
4 Bulk deformation forming (rolling) Rolling typically starts with a rectangular ingots and results in rectangular Plates (t > 6 mm), sheet (t < 3 mm), rods, bars, I-beams, rails etc Figure: Rotating rolls reduce the thickness of the incoming ingot
5 Flat rolling practice The product of the first hot-rolling operation is called a bloom A bloom usually has a square cross-section, at least 150 mm on the side, a rolling into structural shapes such as I-beams and railroad rails. Slabs are rolled into plates and sheets. Billets usually are square and are rolled into various shapes, such as round rods and bars, using shaped rolls Hot rolled round rods (wire rod) are used as the starting material for rod and wire drawing operations
6 Hot rolling and cold rolling The principal rolling processes are hot and cold rolling. Hot rolling is the most common method of refining the cast structure of ingots and billets to make primary shape. Bars of circular or hexagonal cross-section like I- beams, channels, and rails are produced in great quantity by hoe rolling with grooved rolls. Cold rolling is most often a secondary forming process that is used to make bar, sheet, strip and foil with superior surface finish and dimensional tolerances.
7 Schematic of various rolling processes Figure: Schematic of various flat-rolling and shape-rolling processes. Source: S. Kalpakjian, S.R. Schmid: Manufacturing Engineering & Technology, 5 th edition, Prentice-Hall International, 2006; pp. 348
8 Rolling definitions and forces (a) Schematic illustration of the flat rolling process (b) Friction forces acting on the strip surfaces. Source: S. Kalpakjian, S.R. Schmid: Manufacturing Engineering & Technology, 5 th edition, Prentice-Hall International, 2006; pp. 349
9 Independent variables in rolling Roll force Power Speed of exiting strip Final strip temperature Maximum draft Roll strip contact length Sheet or plate shape
10 Dependent variables for rolling Roll speed Amount of thickness reduction Billet thickness and with Billet materials Billet temperature Lubricant
11 Advantages of hot rolling Forces smaller Stresses lower Less power requirement No work hardening Large deformation possible Breaks up the cast structure into preferable form Closes porosity
12 Disadvantage of hot rolling Rolls need to be cooled Materials handling difficult Personnel must be protected
13 Hot rolling microstructure The initial rolling steps of the material typically done by hot rolling (above the recrystalisation temperature of the metal) A cast structure includes coarse and non uniform grains, this structure usually if brittle and may be porous Hot rolling converts the cast structure to a wrought structure with finer grains and enhanced ductility
14 Hot rolling and microstructure
15 Cold rolling Cold rolling is most often a secondary forming process that is used to make bar, sheet, strip and foil with superior surface finish and dimensional tolerances. Cold rolling is carried out at room temperature and, compared with hot rolling, produces sheet and strips with a much better surface finish (because of lack of scale), dimensional tolerances, and mechanical properties (because of strain hardening).
16 Advantage/disadvantage of cold rolling Advantage Work hardening increases strength Excellent surface finish Excellent tolerance on thickness and shape Disadvantage High forces Small reductions give rise to surface stresses and non-uniform stress distribution
17 Thread rolling Thread rolling is a cold-forming process by which straight or tapered threads are formed on round rods or wire by passing them between dies. Threads are formed on the rod or wire with each stroke of a pair of flat reciprocating dies. In another method, threads are formed with rotary dies, at production rates as high as 80 pcs per second.
18 Steps of thread rolling 1. A blank is placed between the two threading dies, and one of the dies moves in translation while the other die remains stationary. 2. The friction between the blank and the dies causes the blank to spin and rolled down the length of the stationary die. 3. The dies are tapered so that as the blank is getting rolled, the threads are being formed in the blank.
19 Thread rolling Creates threads on screws, bolts etc. Advantages: No loss of material Good surface finish Increased strength through cold working a favourable grain flow
20 Machined thread and rolled thread Figure: (a) Features of a machined or rolled thread. Grain flow in (b) machined and (c) rolled threads. Unlike machining, which cuts through the grains of the metal, the rolling threads imparts improved strength because of cold working and favourable grain flow Source: S. Kalpakjian, S.R. Schmid: Manufacturing Engineering & Technology, 5 th edition, Prentice-Hall International, 2006; pp. 363
21 Thread rolling advantages The deformation involved in the rolling process work hardens the threads, resulting in increased strength Rolled threads have improved fatigue resistance. The grain structure in a rolled thread is continuous, as opposed to the cut grains found in a machined product. Rolled thread typically have superior surface finish and a lower cost relative to machined threads
22 Rolling mills Different types of rolling mills and equipment are available with diverse roll arrangements Although the requirement for hot and cold rolling is essentially same, there are important differences in the roll materials, process parameters, lubricants and cooling systems. Highly automated mills produce close tolerance, high quality plates, and sheets at high production rates and low cost per unit weight. Rolling speeds may range up to 40 m/s. The width of rolled products may range up to 5 m.
23 Rolling mills Two-high rolling mills are used for hot rolling in initial break down passes (primary roughing or cogging mills) on cast ingots with roll diameters ranging m. In the three-high mill (reversing mill) the direction of material movement is reversed after each pass, using elevator mechanisms and various manipulators. The plate being rolled, which may weigh as much as 145 tonnes, is raised repeatedly to the upper roll gap, rolled, and then lowered to the lower roll gap and rolled; and so on.. Four-high mills and cluster mills are based on the principle that small-diameter rolls lower roll forces and power requirements.
24 Shape rolling Straight and long structural shapes (such as channels, I-beams, railroad rails, and solid bars) are formed at elevated temperatures by shape rolling (profile rolling) in which the stock goes through a set of specially designed rolls Non-flat shapes can be produced by having rolls with shape: I -beams H- sections Rails Angle irons
25 Stages in shape rolling of H-section Figure: Stages in shape rolling of an I-beam part Source: S. Kalpakjian, S.R. Schmid: Manufacturing Engineering & Technology, 5 th edition, Prentice-Hall International, 2006; pp. 361
26 Ring rolling Thick ring small diameter transformed into thin ring, large diameter Used in jet engines, large ring gears Advantage: Circular shapes with no joines can be made with varieties of cross-sections
27 Roll materials The requirements for roll materials are: Strength and resistance to wear. Common roll materials are: Cast iron Cast steel Forged steel Tungsten carbides are also used for smalldiameter rolls Forged steel rolls, although more costly than cast rolls, have higher strength, stiffness and toughness than cast- iron rolls.
28 Factors affecting rolling The material being rolled The material of the rollers The shape being rolled The size of the stock being rolled The size of the rollers Power requirements
29 Defects in rolled sheet and plate Defects may be present on the surfaces of rolled plates and sheets, or there may be internal structural defects. Several surface defects (such as scale, rust, scratches, gouges, pits, and cracks) have been identified for sheet metals. These defects may be caused by inclusions and impurities in the original cast material or variation other conditions related to material preparation and to the rolling operation.
30 Defects in rolled sheet and plate Source: S. Kalpakjian, S.R. Schmid: Manufacturing Engineering & Technology, 5 th edition, Prentice-Hall International, 2006; pp. 356
31 Defects in rolled sheet and plate Wavy edges on sheets are the results of roll bending. The strip is thinner along its edges than at its centre, thus the edges elongate more than the centre. The cracks are formed as a result of poor material ductility at the rolling temperature. Alligatoring is a complex phenomenon and typically is caused by non-uniform bulk deformation of the billet during rolling or by the presence of defects in the original cast material.
32 References 1. S. Kalpakjian, S.R. Schmid: Manufacturing Engineering & Technology, 5 th edition, Prentice-Hall International, E. Paul Degarmo, J. R. Black, R. A. Kohser; Materials and Processes in Manufacturing, 9 th edition, John Wiley & Sons, Inc, R. L. Timings, S. P. Wilkinson: Manufacturing Technology, 2 nd edition, Pearson Education Limited, London, 2000.
Example: 1 A 300-mm-wide strip 25 mm thick is fed through a rolling mill with two powered rolls each of radius = 250 mm. The work thickness is to be reduced to 22 mm in one pass at a roll speed of 50 rev/min.
TARIFF CODE and updates standard No HS CODE AHTN CODE PRODUCT DESCRIPTION PRODUCT TYPE STANDARDS IDENTIFIED 7207 Semi finished products of iron or non alloy steel Containing by weight less than 0.25% of
For comments only BUREAU OF INDIAN STANDARDS Draft Indian Standard STRUCTURAL STEEL (ORDINARY QUALITY) ICS 77.140.01 ------------------------------------------------------------------------------------------------------------------------------------------------
Data Sheet: A2.2 High carbon and quenchable steels Hot Rolled Steel Plate and Coil for Hardening and Wear Resistance General description Steel is generally classified as high carbon steel if the nominal
5. DIMENSIONS, TOLERANCES AND SURFACE 5.1 Dimension, Tolerances and Related Attributes 5.2 Surfaces 5.3 Effect of Manufacturing Processes Introduction Dimensions the sizes and geometric features of a component
Tube drawing is very similar to bar drawing, except the beginning stock is a tube. It is used to decrease the diameter, improve surface finish and improve dimensional accuracy. A mandrel may or may not
Blanking of Stainless Steel Sheets for Mass-Production Cold Pressing 304 Stainless.23 mm Thk. D2 (HRC 59/60) 500 C HRC 62/63 520 C 50mm x 300mm x 420mm Evaluation 110,000 shots 240,000 shots 127% Increase
SFSA: Article Castings or Forgings? A Realistic Evaluation An honest presentation of the advantages and limits of both steel component forms allows users to make informed choices when considering a forged
Working Drawing and Assemblies Chapter 10 Objectives 1.Define working drawings. 2. Describe how working drawings are used in industry. 3. List the major components of a complete set of working drawings.
Module 4 Design for Assembly Lecture Design for Heat Treatment 7 Instructional objectives By the end of this lecture, the student will learn 1. different heat treatment processes, 2. application of various
MET 33800 Manufacturing Processes Chapter 42 Thread and Gear Manufacturing Before you begin: Turn on the sound on your computer. There is audio to accompany this presentation. THREAD MANUFACTURING Screw
4.1 Introduction 4. GRINDING MACHINE Grinding is a metal cutting operation like any other process of machining removing metal in comparatively smaller volume. The cutting tool used is an abrasive wheel
1 Unit 6: EXTRUSION Introduction: Extrusion is a metal working process in which cross section of metal is reduced by forcing the metal through a die orifice under high pressure. It is used to produce cylindrical
CHAPTER1 Fundamentals of Extrusion The first chapter of this book discusses the fundamentals of extrusion technology, including extrusion principles, processes, mechanics, and variables and their effects
Sheet metal operations - Bending and related processes R. Chandramouli Associate Dean-Research SASTRA University, Thanjavur-613 401 Table of Contents 1.Quiz-Key... Error! Bookmark not defined. 1.Bending
Die casting Die casting is a moulding process in which the molten metal is injected under high pressure and velocity into a split mould die. It is also called pressure die casting. The split mould used
Analysis of strip rolling - 1: R. Chandramouli Associate Dean-Research SASTRA University, Thanjavur-613 401 Joint Initiative of IITs and IISc Funded by MHRD Page 1 of 10 Table of Contents 1. Analysis of
MARTENSITIC STAINLESS STEEL RWL-34 RWL 34 is a Rapid Solidified Powder (RSP) Martensitic Stainless Steel, which is variation of the 420 martensitic stainless steel family with minimum 13 percent chromium
Forging stock standards guideline Issue n 10 FORGING STOCK 30 Microstructure 34 Grain size Air melted (except if δ ferrite or problem 1 per batch) 50 Cleanness/ Inclusion See EN 2157-2. 51 Macrostructure
Laboratory 1 Tensile Testing Objectives Students are required to understand the principle of a uniaxial tensile testing and gain their practices on operating the tensile testing machine. Students are able
REFERENCE CATALOGUE Progressive, modern, innovative that s what Brunswick Steel is all about. Established in 1970 as a family owned business, Brunswick Steel initially began as a demolition and salvage
Mission Statement State Steel strives to provide quality products and services at competitive prices. This commitment is demonstrated with several branch locations all offering large, diverse inventories
Workshop files pictograms and their meaning Angle grinders Bench grinder/polishing machine Off-hand grinding Band filing machine Eccentric grinders Flexible drive shaft Straight grinders Orbital sanders
> Ultra-fine grain carbides are characterized by a very high hardness and wear resistance. They are used for milling tools and drills for processing abrasive, soft and tough materials, in nozzles and in
Manufacturing process What is Manufacturing Process? A sequence of operations, often done on a machine or at a given area. Examples: welding, casting, cutting, assembling, etc. During a manufacturing process,
Homework solutions for test 2 HW for Lecture 7 22.2 What is meant by the term faying surface? Answer. The faying surfaces are the contacting surfaces in a welded joint. 22.3 Define the term fusion weld.
Training Objective After watching the program and reviewing this printed material, the viewer will gain knowledge and understanding of the basics of the drills and machines used in a variety of holemaking
North American Stainless Long Products Stainless Steel Grade Sheet 2205 UNS S2205 EN 1.4462 2304 UNS S2304 EN 1.4362 INTRODUCTION Types 2205 and 2304 are duplex stainless steel grades with a microstructure,
For New Technology Network R Steel Manufacturing Machinery Product Guide Book Ecological / Economical proposals from NTN NTN products exhibit benefits at various locations. Steel manufacturing equipment
Engineering Material Ferrous material; A general classification of engineering materials is shown in Figure 1.8. Engineering material can be broadly classified as Metallic and Non-Metallic materials. The
Ceramic processing The higher performance of ceramics is the result of strict control ol of purity, composition, microstructure and processing. Because of their inherent brittleness, ceramics cannot be
Products EschmannStahlGrades Plastic Mould Steel Hot Work Tool Steel Cold Work Tool Steel Overview High quality, Comprehensive and applicationoriented We Have the Right Solution High Quality and Quickly
Aluminum Pure aluminum is soft and ductile and most commercial uses require greater strength than pure aluminum affords. So, strength is achieved by the addition of other elements to produce alloys. Further
Designation: A 68 8 Standard Specification for Tool Steels Alloy This standard is issued under the fixed designation A 68; the number immediately following the designation indicates the year of original
Training Objective After watching the program and reviewing this printed material, the viewer will learn the essentials of the various metal casting processes used in industry today. The basic principles
Training Objective After watching the program and reviewing this printed material, the viewer will gain a knowledge and understanding of the basics of powder metallurgy. Types of particles are explained.
Material Science Engineering and Steel Making/Metallurgy Stark County High Schools 2016 Agenda What is Material Science Engineering Basics of Steel Making Steel Processing and Properties 2 What is Material
INDUCTION WELDED SMALL DIAMETER TUBE PRODUCTION LINE Target Production of welded single - wall tubing manufactured to ASTM A 513, also zinc coated as per UNI 5741-66, suitable for many low pressure and
ENGINEERING COMPONENTS EDEXCEL NATIONAL CERTIFICATE/DIPLOMA MECHANICAL PRINCIPLES OUTCOME ENGINEERING COMPONENTS TUTORIAL 1 STRUCTURAL MEMBERS Structural members: struts and ties; direct stress and strain,
MACHINE RECCOMENDATIONS PVC requires reciprocating screw injection moulding machine with a plasticising screw to produce homogeneous melt. It is recommended that a shot weight of the part should take two
AUSTENITIC STAINLESS DAMASCENE STEEL Damasteel s austenitic stainless Damascene Steel is a mix between types 304L and 316L stainless steels which are variations of the 18 percent chromium 8 percent nickel
Designation: A 600 92a (Reapproved 2004) Standard Specification for Tool Steel High Speed This standard is issued under the fixed designation A 600; the number immediately following the designation indicates
7.0 Heat Treatment The microstructures of the CuAlNiFe and CuMnAlFeNi alloy groups are quite complex due to the range of phases which exist within the system. Nickel aluminium bronze may be subjected to
s 410, 420, 425 Mod, and 440A GENERAL PROPERTIES s 410, 420, 425 Modified, and 440A (see composition on Page 2) are hardenable, straight-chromium stainless steels which combine superior wear resistance
JOURNAL OF CURRENT RESEARCH IN SCIENCE (ISSN 2322-5009) CODEN (USA): JCRSDJ 2014, Vol. 2, No. 2, pp:277-284 Available at www.jcrs010.com ORIGINAL ARTICLE EXPERIMENTAL AND NUMERICAL ANALYSIS OF THE COLLAR
Machining (Reading: Chap 8 in Kalpakjian and Schmid) Outline Chip formation during machining Force and power requirement Mechanisms of tool wear and fatigue Types and properties of cutting-tool materials
Lapping and Polishing Basics Applications Laboratory Report 54 Lapping and Polishing 1.0: Introduction Lapping and polishing is a process by which material is precisely removed from a workpiece (or specimen)
Guideline No.: W-22(201510) W-22 STAINLESS STEEL PIPES Issued date: October 20,2015 China Classification Society Foreword: This Guide is a part of CCS Rules, which contains technical requirements, inspection
High speed machining and conventional die and mould machining Reprint from HSM - High Speed Machining There are a lot of questions about HSM today and many different, more or less complicated, definitions
Tensile test Adam Zaborski handouts for Afghans Outline Tensile test purpose Universal testing machines and test specimens Stress-strain diagram Mild steel : proportional stage, elastic limit, yielding
Training Objectives After watching the program and reviewing this printed material, the viewer will gain knowledge and understanding of the stamping process and the die systems used to form sheet metal.
MULTIVER GLASS GLASS HEAT TREATMENT TEMPERED GLASS HEAT-STRENGTHENED GLASS HEAT SOAK TESTED TEMPERED GLASS DATA SHEET / Quebec Version 2.0 Type of Glass Offered by Multiver TEMPERED GLASS To increase the
INTERNATIONAL JOURNAL OF MECHANICAL ENGINEERING AND TECHNOLOGY (IJMET) International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 6340(Print), ISSN 0976 6340 (Print) ISSN 0976 6359
19. Quad -rings The sealing principle of the Quad ring is nearly the same as the O-ring sealing. The initial sealing is achieved by the diametrical squeeze in a right angled groove. The system pressure
LEADER IN CUTTING TECHNOLOGY FOR OVER 2 YEARS REASONS WHY TRONEX IS THE BEST IN THE WORLD 1 2 SUPERIOR CUTTING PERFORMANCE Cut hundreds of thousands of times before dulling. Cut hundreds of thousands of
FATIGUE CONSIDERATION IN DESIGN OBJECTIVES AND SCOPE In this module we will be discussing on design aspects related to fatigue failure, an important mode of failure in engineering components. Fatigue failure
METU DEPARTMENT OF METALLURGICAL AND MATERIALS ENGINEERING Met E 206 MATERIALS LABORATORY EXPERIMENT 1 Prof. Dr. Rıza GÜRBÜZ Res. Assist. Gül ÇEVİK (Room: B-306) INTRODUCTION TENSION TEST Mechanical testing
HOME OFFICE SPECIFICATION FOR SEAMLESS ALLOY STEEL CYLINDERS FOR THE CONVEYANCE OF COMPRESSED GASES HOT 1 Cylinders manufactured to these specifications shall be manufactured by a cylinder manufacturer
Third Edition Hot Rolled and Structural Steel Products HOT ROLLED AND STRUCTURAL STEEL PRODUCTS C ONTENTS Introduction 2 Availability Structural Steel Sections 2 Rail Products 4 Merchant Bar Sections 6
Page 1 of 5 MEEHANITE SELECTION GUIDE Presented by Lodi Iron Works, Inc 1-888-368-5395 General Engineering Applications Meehanite Flake Graphite Types -Type AQ is a wear and abrasion resisting iron that
PAGE 1 OF 6 PREFERRED RELIABILITY PRACTICES EDDY CURRENT TESTING OF AEROSPACE MATERIALS Practice: Eddy Current Testing (ECT) can be used on electrically conductive material for detecting and characterizing
FAILURE MODES and MATERIALS PROPERTIES MECH2300 - Materials Lecture 10 R. W. Truss Materials Engineering R.Truss@uq.edu.au COMPONENT FAILURES Structures lectures es on component es cause response in component
Introduction to Metallography Metallography has been described as both a science and an art. Traditionally, metallography has been the study of the microscopic structure of metals and alloys using optical
Standard Caps you are here: Home > Weldbend Catalog > Fittings > Caps Caps STANDARD WEIGHT Inches / Pounds For Metric Units >Click Here Nominal Pipe Size Outside Inside Wall Thickness (T) Length (E) Pipe
CAST IRON 2P GREY IRON C Mn Si Ni Cr Mo P S Al Cu 3.25 0.55 2.30 0.08 0.4 0.1 0.1 0.8 0.1 0.7 1830-T260 1452-Grade 17 1691-GG35 FC-25 2P is normally called for when exceptionally good wearing qualities
BENDING, ROLLING, FORMING, SHEARING AND PUNCHING BISPLATE FORMING COLD FORMING All of the BISPLATE quenched and tempered steel grades can be cold formed, using brake press bending or plate rolling techniques.
ATI 2205 Duplex Stainless Steel (UNS S31803 and S32205) GENERAL PROPERTIES ATI 2205 alloy (UNS S31803 and/or S32205) is a nitrogen-enhanced duplex stainless steel alloy. The nitrogen serves to significantly
Pierre Marchand, product director, speciality product Meeting NEI-NRC March 14th 2013 Agenda Dubuc works: location and overview MMC fabrication process at Rio Tinto Alcan Boralcan product caracteristics
Comparison of BS and BS EN for steel materials Appendix This table only highlights the comparison of BS and BS EN on steel materials, which are relevant to plan approval. Title of BS BS BS EN/other Title
Module 4 General Purpose Machine Tools Lesson 18 Kinematic system and operations of drilling machines Instructional Objectives At the end of this lesson, the students will be able to : (i) State the basic
High-strength and ultrahigh-strength TM steels Cut sheet from hot-rolled steel strip and heavy plate Josef Elmer, Key account manager voestalpine Steel Division www.voestalpine.com/steel Weight savings
Converting from Steel to Ductile Iron Yields REPRINTED FROM THE FLUID POWER JOURNAL for n today s competitive market, hydraulic component manufacturers are constantly faced with the task of making parts
Naue GmbH&Co.KG Quality Control and Quality Assurance Manual For Geomembranes July 2004 V.O TABLE OF CONTENTS 1. Introduction 2. Quality Assurance and Control 2.1 General 2.2 Quality management acc. to