Abstract
As the pressure for production increases, so is the pursuit for efficiency. This is why today, in many manufacturing processes, two-zone control of rolling is being adapted. This paper explores the fundamentals of two-zone rolling, the benefits and limitations associated with it, as well as the requirements necessary to carry out the process.
Introduction
Two-zone control of rolling is a method of metal forming used to produce metal components with improved formability and strength. Its a form of hot rolling, whereby metal plates are passed through two sets of rolls, each one set to a different temperature. This allows the metal plate to both be formed and to be subjected to temper rolling. This process is often used to produce metal components with increased ductility, toughness and surface condition.
The Basics of Two-Zone Rolling
In two-zone rolling, a metal plate is first heated above its recrystallization temperature. The heated plate is then passed through two sets of rolls, each set at different temperatures. The first set of rolls, known as the pre-bend set, is set to a lower temperature than the second one, known as the temper set. As the metal plate passes through the pre-bend set of rolls, it is compressed into the desired shape. This hot forming process allows the metal plate to be formed while softened. The metal plate is then passed through the temper set of rolls which provides additional compression, in addition to tempering the plate to achieve the desired properties.
Benefits and Limitations of Two-Zone Rolling
Two-zone rolling has several advantages over traditional hot rolling. For instance, it can produce metal parts with improved ductility, toughness and surface condition. In addition, the process eliminates scrap, which reduces production costs. Furthermore, two-zone rolling facilitates the production of complex shapes, thereby reducing the need for costly cutting and slotting operations.
Despite its advantages, two-zone rolling also has its limitations. The process is not suitable for large parts due to its high cost, and it requires extremely precise temperature control due to the presence of two sets of rolls. Moreover, it can cause surface defects such as cracking and tearing when carried out without proper attention to the important parameters.
Requirements for Two-Zone Rolling
Two-zone rolling requires several components and a careful control of temperature. The most important components are the pre-bend and temper rolls. These rolls must be of the highest quality to ensure accuracy and reliability. The temperature must also be carefully controlled, as the process requires precise preheating of the plate and precise control of the rolls temperatures. Furthermore, the pre-bend and temper rolls must have a high-level of formability in order to produce the desired form.
Conclusion
Two-zone roll forming is a process used to produce metal components with improved formability and strength. The process involves pre-heating a metal plate before passing it through two sets of rolls at different temperatures. The process offers several benefits, such as improved ductility, toughness and surface condition, as well as the reduction of scrap material. However, it can also present certain limitations and requires precise temperature control in order to produce components without defects.
