The Physical Technical Institute of the National Academy of Sciences of Belarus (the PTI NAS Belarus) was founded in 1932. About 370 people work for the Institute at the moment.
The PTI NAS Belarus conducts fundamental researches in the fields of the plasticity and durability theory, phase and structure conversion in metals and alloys, thermal physics, pulse and electric physical methods of metal treatment; the Institute develops new processes for receiving and treating machine-building materials and products.

CWR Mill
CWR Scheme
CWR Process
CWR Tool

The development of theoretical basis for the cross-wedge rolling (CWR) process and creation of new technologies, equipment, and tools for their realization are the main activity of the Department of Technological Deformability. The head of the department from the moment of its foundation is Dr. Schukin. School which was created by him is known as the leading in the world. Here the classical theory of the cross-wedge rolling is developed. The Department conducts the fundamental and applied researches the goal of which is the solving of a scientific problem of augmentation of the effectiveness of the Metal Pressure Treatment at the expenses of more complete usage of plastic metal properties. 30% of the inventions belong to the Institute, 50% of the CWR equipment in the world is produced in Belarus. More than 100 items of rolling equipment of different modifications sold in the CIS and Western countries. The Belarusian equipment works in Russia, the Ukraine, Bulgaria, the Czech Republic, Germany, Spain, the USA, Poland, and Turkey. One rolling mill of the Institute construction stands for 5 items of lathes and saves at the two-shift work up to 800 tons of metal per year. The mill begins to get profit in less than a year.

Cross-wedge rolling (CWR) is a high-performance resource-saving technology of metal pressure processing with operating ratio of metal utilization (RMU) 0.8-0.98. One can produce with the help of the CWR method such details as solids of revolution with the lengthened axis, shaping of which is carried out by redistribution of metal along an axis of preform with flat wedge tool driven across the axis. The configuration of details is rather versatile: with cylindrical, conical and nodular surfaces with every possible grooves and ledges. Received details have peculiar features of high resistance and wearability while in service. With the help of the CWR method can be treated practically all constructional steels, as well as yellow metal, titanium, zirconium and nickel.


With the help of the mechanism of transition a blank is fed into the working cage of the mill and is laid across the starting part of the wedge tool. At the straight stroke of the mill’s upper plate the billet is rolled between movable upper and unmovable lower wedge tools. The both tools have side inclined edges that make the metal surplus move to butts in that way lengthening the blank. The rest metal part is rolled between the tools.
At the final stage of forming the knives on the both sides of the tools cut edge waste from the finally formed part. It slithers into the receiving cage. The movable tool goes to the starting position.


Out of well-known basic CWR schemes mostly wide-spread are flat-wedge and roller rolling on the basis of which appropriate kinds of equipment have been designed.The advantages and disadvantages of each kind have been revealed while in service.
To disadvantages of roller mills should be referred complexity and high labour input of manufacturing of roller tool engraving which is carried out on special lathes. The subsequent heat treatment does not provide the hardness corresponding to hardness of a flat tool. As a result, the resistance of a roller tool is lower than the flat tool’s resistance. Besides, turning processing of an engraving provides its lower accuracy in comparison with a polished engraving of a flat tool, and that leads to reduction of rolled parts’ accuracy.

Flat rolling mills have a number of advantages in comparison with roller mills:
• simplicity of manufacturing and low cost of flat wedge tools produced on universal milling and grinding equipment;
• stable position of a part on the plane of the tool;
• high accuracy of dimensions (±0.01... ±0.5 mm) of rolled parts;
• high resistance of flat wedge tools (up to 0.5 million parts);
• low steel intensity of the equipment;
• simplicity of regulation and adjustment of the mill;
• quick reset of the equipment on releasing new parts, full automatization of the process.

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