COLD ROLLING OF USED PIPES

Abstract

The relevance of the work is caused by the need to develop a technology for cold rolling of pipes applying the used hot-rolled pipe. The technology is being developed with the aim of saving geo-resources and increasing the economic efficiency of pipe production using cold pilger rolling. The aim of the work is to develop a cost-effective technology for converting the used pipes into a different type of pipe product. The finished pipes obtained in this way must have sufficient quality parameters for safe operation. Methods: theoretical studies of the technological processes of cold rolling of pipes on roll and cold pilger rolling mills, development of deformation modes and technology for cold rolling of used pipes, suitable for implementation at existing production, with minimal costs for the implementation of such technology. Results. The authors developed and proposed for use the efficient (from both environmental and economic points of view) technology of cold rolling of industrial batches of pipes using billets from used pipes. The developed technology does not require significant investment. All the equipment required for its implementation is available in the cold-rolling pipe shops. The rolling technology itself practically does not differ from the standard one. Changes are introduced only in those operations of the technological process that relate to the preparation of the original workpiece for the first pass. Since up to 70–80 % of the cost of cold-worked pipes is the cost of a hot-rolled or hot-pressed billet, the use of the used pipes allows not only reducing the anthropogenic load on the environment, but increasing as well the commercial efficiency of the production of cold-rolled pipes. The finished pipes obtained by the developed method will have sufficient quality parameters for their trouble-free operation. The technology was tested in the existing cold-rolling tube shop.

Keywords

• cold rolling of pipes
• used pipes
• billet
• technology
• processing
• environment
• reduction of anthropogenic impact