ROLLING Abdulrahman Almaidani 201500745 Noor Almutairi 201500970 Outline

ROLLING Abdulrahman Almaidani 201500745 Noor Almutairi 201500970

Outline • Introduction • Rolling process • Application • Hot and Cold of rolling

Introduction • Rolling is one of the most important industrial metal forming operations. Hot Rolling is employed for breaking the ingots down into wrought products such as into blooms and billets, which are subsequently rolled to other products like plates, sheets etc. • Rolling is the plastic deformation of materials caused by compressive force applied through a set of rolls. The cross section of the work piece is reduced by the process. The material gets squeezed between a pair of rolls, as a result of which the thickness gets reduced and the length gets increased.

Rolling Process • Terminology : - Ingot - Blooms - Slab - Billets - Sheet

Rolling Process

Application • Rolling is used for making hollow seamless tubes, rods etc. • Large length cross sections such as rails. • It is use for mass production of threaded parts like screw, bolts etc. • Gears can be cut on gear blank by rolling process

Hot Rolling • Advantages: • Hot rolling can greatly reduce energy consumption and costs. • The metal plastic deformation is high during hot rolling. • Disadvantages: • After hot rolling, non-metallic inclusions (mainly sulfides and oxides, as well as silicates) inside the steel are pressed into thin sheets. • Hot rolling does not control the mechanical properties required for the product accurately, and the microstructure and properties of the hot rolled product are not uniform.

Cold Rolling • Advantages: • Fast forming speed. • Can be made into a variety of cross-section forms. • Cold rolling can make the steel produce a large plastic deformation, thus improving the yield point of the steel. • Disadvantages: • Higher forces required for deformation. • Heavier and more powerful equipment required. • Less ductility available. • Metal surfaces must be clean and scale-free.

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