Pass Parameteric Design And Optimization Of Heavy Rail In Hot Rolling Process

Since the rail invention in 1767, it has been playing a very important role in the economic development process. Its profile has also experienced a series of improvement and perfection. Now it is widely using in passenger and freight transportation, mining transportation and crane rail transportation. At present, there are many types of rail in our country according to their single weight it can be divided into light rail and heavy rail, the heavy rail mainly used in passenger and freight transportation, its intrinsic quality directly related to the safety of passenger and freight rail transportation. Research on how to improve the production efficiency and product quality base on the existing heavy rail production conditions, will have a very important significance.At present, the research about heavy rail has gradually turned to the universal rolling method, the research of the traditional rolling method mostly very early, and the studies of the traditional rolling method by the modern tools is very few, during the rolling process, the basic dimensions of heavy rail such as the rail-height, the bottom width, and the waist thickness is mainly controlled by rely on the experience, and there are many limitations during its design.This paper has programed a heavy rail Computer-aided Roll Pass Design System, and referred to as Heavy Rail-CARD. The system can implement CAD visual programming based on the product specifications and pass, and established a good user interface and perfect pass parameter database. Considering the actual production experience and other factors, the system has strong parameter modify function, it can achieve that the data real-time input and the graphics real-time output.In this paper, choose U71 Mn steel as material of the heavy rail, researched the material mechanics performance of U71 Mn steel on Gleeble-3500 and obtained the stress- strain curve of U71 Mn steel.In this paper, choose 50kg/m rail rolling production line as the research object, use Inventor software built a three-dimensional solid model of the heavy rail stock and the each rack with rollers, finished the 12 passes finite element analysis from the start rolling to finish rolling of heavy rail by DEFORM-3D software, consider the given parameters of unit and cross-sectional shape of the product, study the rolling contact at the pass rolling deformation, analyzed the stress field, strain field and rolling force of each pass during the heavy rain rolling. Analyzes the rationality of the pass system, and given proper optimization.This study, for predict the product performance, establish rolling schedule and improve the production process of heavy rolling has some guiding function, and have certain significance to improve productivity efficiency and the product quality of heavy rail.