PNIPU: Engineering tool to accelerate the production of optical fiber

Main article: Fiber optic cable

2025: Optical Fiber Manufacturing Tool Development

Perm Polytechnic scientists have developed an engineering tool that optimizes the production of optical fiber by 2 times. This was announced on December 11, 2025 by the press service of PNIPU.

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Фото: PNIPU

According to the company, modern, Internet digital communication Medicine and highly dependent on the quality of fiber optic cables. However, their production is a complex process, where an error in the fraction of a millimeter or degree leads to damage to the entire workpiece. The main difficulty is that industrial the machines are programmed to process parts of strictly defined, reference dimensions. However, the actual raw materials always have slight deviations due to technological features. In this case, technologists are forced to select equipment settings "by eye," which sharply increases the proportion of scrap and reduces the efficiency of optical fiber production. Scientists Perm Polytechnics have created an engineering tool that calculates ideal parameters for any workpiece. The introduction of the method will make it possible to speed up processing twice and reduce the share of defective products by 75%. The article was published in the journal "Bulletin of PNIPU., Electrical equipment Information Technologies, Control Systems."

Optical fiber is the basis of the modern Internet, communication and many medical devices. Its production is a very complex process, requiring accuracy at every step. Even slight deviations in technology can lead to a significant increase in the cost of the finished material and to the fact that an expensive workpiece will be unsuitable for further use.

One of the key initial stages of fiber development is the process of "jacketing" quartz pipes. This is the process where a thin quartz tube is gently heated and placed on a production rod. Jacketing is necessary to create a strong and thick workpiece, from which a thin optical fiber is then drawn.

However, the equipment for this process is typically designed to handle several standard tube sizes. In practice, the size of raw materials may differ slightly from the ideal. Thus, the lack of instructions for different types of blanks forces the technologist to select settings by methods of calculating intermediate values ​ ​ between several known established modes. However, this approach does not work, because heat and mass transfer processes obey more complex, non-linear laws.

As a rule, in such a situation, a specialist has to manually adapt all settings. Most often, this is done by simple adjustment. For example, if the diameter of the tube is 2% larger than the standard diameter, the fiber heating rate is intuitively reduced by about the same 2%. However, the jacketing process is influenced by many interrelated factors, and an approximate adjustment of one parameter cannot account for all aspects of production. As a result, an expensive workpiece can lose its optical properties, and the percentage of scrap will increase, increasing the cost of the final product.

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Фото: PNIPU

Optimal operating modes are also often protected by companies as production secrets (know-how). This leads to the fact that there are practically no scientifically substantiated and publicly available methods for calculating parameters for such a process. As a result, this creates a lack of knowledge, interferes with the standardization of the industry and slows down general technological progress.

Perm Polytechnic scientists have created a universal engineering tool for the jacket process. It will allow twice to optimize the processing of blanks with non-standard dimensions and reduce the share of scrap in production by 75%.

At first, experts analyzed the entire cycle of jacketing, breaking it down into key stages. They focused on the three most important ones: etching (surface cleaning), polishing, and fusing the tube to the rod.

For each stage of production, scientists created their own virtual model: they indicated the dimensions of the quartz tube, rod and gap between them, set the properties of the materials and prescribed how the burner moves, with what power it warms, and proposed a method for calculating temperature fields in quartz.

Further, in the created digital models, they began to change the original parameters as it happens in reality: they varied the thickness of the wall of the tube, its diameter, the speed of movement of the burner and many other factors. The created computer program for each option calculated how the system would behave and whether the result would meet the quality criteria.

The scientists tested their models using real factory data. They took the standard dimensions of pipes and rods from the industrial standard, as well as the actual operating modes of the burner with its speeds and temperatures. The calculations also took into account the exact properties of quartz materials and gases from professional databases to ensure that the virtual model works with the same parameters as the physical process.

The final and most practical step was to transform an array of complex data into a production-friendly tool. Based on the identified patterns, we built the so-called technological nomograms. In fact, this is a set of visual instructions that reflect the measured parameters of the tube (for example, diameter and thickness), as well as what speed of movement of the burner should be set for such indicators. told Daria Vladimirova, Candidate of Physical and Mathematical Sciences, Associate Professor of the Department of Applied Mathematics, PNIPU

For an employee in production, the solution boils down to a simple and quick search for the desired values ​ ​ on nomograms. At the beginning of the work, he measures the dimensions of the real tube and, relying on the graphics created during modeling, finds all the necessary parameters: at what speed to move the burner, what power to set or how much gas to supply. Thanks to the ready-made tool, even for non-standard pipes, you can instantly find the correct settings without wasting time on errors or risking spoiling the workpiece.

As a result, working with non-standard blanks has become twice as effective, because there is no need for a long selection of parameters. It is also important that the number of rejects at the main stages of production decreased by 75%. This means that expensive raw materials are now consumed more economically, and the quality of finished products has become consistently high. Our development will help create a common scientific base for an important industry, since previously such knowledge was often a trade secret. reported Vladimir Pervadchuk, Doctor of Technical Sciences, Head of the Department of Applied Mathematics, PNIPU

The very approach used by scientists can be applied in other areas. The method of creating an accurate computer model of a complex process, and then simple instructions for workers, is suitable for many high-tech industries.

For example, it can be used to control the melting of special glass, where bubbles and inhomogeneities are unacceptable. The specialist, having measured the temperature and viscosity of the alloy, could immediately determine, according to the finished instructions, how to adjust the furnace mode. Similarly, the proposed tool would be able to tune chemical reactors to synthesize complex substances. According to the sensor readings about the temperature and concentration of the components, the technologist would find accurate values ​ ​ for adjusting the supply of reagents.