ISSN (print) 1995-2732
ISSN (online) 2412-9003


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Thin-walled pipes made of corrosion-resistant steels are widely used in aviation, rocket engineering, space technology, shipbuilding, machine building, ferrous and non-ferrous metallurgy, as well as nuclear power, chemical, oil and gas and other industries. Pipe bending is one of the key processes in the production of pipeline components. During pipe bending and rolling, thermal phenomena dictate the temperature in the bending zone, the wear rate of the tool (rolling balls), and hence its durability. To establish the heat distribution pattern in the bending zone, we conducted a series of natural experiments using an artificial thermocouple and a thermal imager. The artificial thermocouple was used because it is a simple, reliable, and easily available tool. All the necessary measurements were taken on a special pipe bending machine designed for small diameter pipes. All temperatures were recorded using a thermal imager. There were experiments carried out with and without a coolant. To obtain a spatial pattern of heat distribution in the treatment zone and to establish a relationship between the temperature and the bending time and phase, a series of measurements was taken with the industrial thermal imager FLIR P65 on a custom-built machine of the SKhGT-3 model designed at SUSU. Curves were built showing the temperature variations in the rolling zone when 10 points are covered in one time. A comparison was made of two temperature measuring techniques. Temperature was measured in the rolling zone with no coolant used, and temperature was measured at the pipe surface, which noticeably differs from the temperature on the rolling tool due to heat dissipation across various components of the process system, the workpiece and the environment. The study found that an extended processing period makes the effect of low-temperature tempering of the tool more probable, which makes the use of highly effective cooling agents a pre-requisite condition.


Thermal phenomena, pipe bending, custom-built machine, artificial thermocouple, thermal imager.

Andrey V. Bobylev – PhD (Eng.), Head of the Department of Mechanical and Machine Tool Engineering,

South Ural State University, Chelyabinsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Aleksandr V. Kozlov – DSc (Eng.), Professor

South Ural State University, Chelyabinsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Sergey P. Maksimov – PhD (Eng.), Dean of the Faculty of Machinery and Technology,

South Ural State University, Chelyabinsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Evgeny V. Khaliulin – Engineer, Postgraduate Student

South Ural State University, Chelyabinsk, Russia

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