Design principes of single-stage rolling mills for machine-building industries

Abstract

The use of variable profiles in engineering is the most effective way to reduce metal consumption and improve performance, increase the lifetime, reliability of machines and mechanisms, and reduce costs for their production, repair and operation. The purpose of the present work is to systematize the blanks of machine-building industries obtained by methods of plastic deformation and to develop general principes of the con cept of creating single-stage rolling mills on the basis of analysis of their design and operation. Three main classes of profiles are distinguished, differing in the type of the initial workpiece: strip, shaped and tube periodic billets. All these types of blanks can be used as semi-finished products for the production of the main parts of suspension and chassis of cars. Strip billets are widely used for the manufacturing of elastic suspension elements, tubular – for manufacturing of hollow body parts with increased requirements for strength and rigidity, in particular, driving axle housing, semi-axles of cars and trailers, jet engine casings. Shaped periodic profiles of various shapes are used as blanks for hot volumetric stamping. Mills and automatic lines for the rolling of blanks of low-spring springs, under-springs, guide bearings of air suspension, rolling of the bars of the front axle beam, manufacturing of protective elements and semi-axes of agricultural machinery developed under the guidance or with the direct participation of the author are presented. General requirements for the deformation equipment of machine-building industries are formulated. Recommendations to use induction heating and high-temperature thermomechanical treatment are justified. It is not recommended to change the direction of movement of the workpiece in the process chain. As a power drive equipment it is better to take electromechani cal, rather than hydraulic systems. It is also advisable to choose separate drives for each working element of the equipment.