Piotr Boral

Dr. Piotr Boral

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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30 November 2023 in Materials
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PBPiotr Boral
Piotr Boral
Rafał GOŁĘBSKIRafał GOŁĘBSKI
Rafał GOŁĘBSKI
RKRuzena Kralikova
Ruzena Kralikova
Gear drives are widely used in various fields and applications due to their properties and capacity. Their versatility, durability, and ability to transmit high torques as well as precision and reliability make them extremely useful in many fields of technology. They are widely used in industrial and energy machinery, vehicle drive systems, aerospace, medical devices, and many other areas. Gears can be manufactured using many technologies. This work focuses mainly on machining with particular emphasis on high-performance new technologies. The process of mathematical modeling of the gear and the machined profile is strongly related to CNC machining technologies. A robust correlation of systems supporting the design and modeling of sliding gears needed for the manufacturing process is presented in the article. It is very important to properly assess gears with correct manufacturing in accordance with a specific standard. The article presents an analysis of available methods for controlling gears using coordinate measurement techniques. Gear machining methods were assessed in terms of the technologies used as well as their productivity and manufacturing tolerance.

28 May 2021 in Materials
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Rafał GOŁĘBSKIRafał GOŁĘBSKI
Rafał GOŁĘBSKI
PBPiotr Boral
Piotr Boral
Classic methods of machining cylindrical gears, such as hobbing or circumferential chiseling, require the use of expensive special machine tools and dedicated tools, which makes production unprofitable, especially in small and medium series. Today, special attention is paid to the technology of making gears using universal CNC (computer numerical control) machine tools with standard cheap tools. On the basis of the presented mathematical model, a software was developed to generate a code that controls a machine tool for machining cylindrical gears with straight and modified tooth line using the multipass method. Made of steel 16MnCr5, gear wheels with a straight tooth line and with a longitudinally modified convex-convex tooth line were machined on a five-axis CNC milling machine DMG MORI CMX50U, using solid carbide milling cutters (cylindrical and ball end) for processing. The manufactured gears were inspected on a ZEISS coordinate measuring machine, using the software Gear Pro Involute. The conformity of the outline, the tooth line, and the gear pitch were assessed. The side surfaces of the teeth after machining according to the planned strategy were also assessed; the tests were carried out using the optical microscope Alicona Infinite Focus G5 and the contact profilographometer Taylor Hobson, Talysurf 120. The presented method is able to provide a very good quality of machined gears in relation to competing methods. The great advantage of this method is the use of a tool that is not geometrically related to the shape of the machined gear profile, which allows the production of cylindrical gears with a tooth and profile line other than the standard.

15 September 2022 in Materials
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PBPiotr Boral
Piotr Boral
Rafał GOŁĘBSKIRafał GOŁĘBSKI
Rafał GOŁĘBSKI
Cylindrical worms are generally machined by the hobbing method using rotary tools, and they are formed in the finishing pass at the full profile height. In this case, the profile of the tool-action surface determines the profile of the machined surface, and for technological reasons, a rectilinear (less frequently circular) axial profile of the tool-action surface is generally assumed. In the currently known technology, machining takes place on special machine tools, and on tools that are specially prepared for a specific outline. The research objective of the article is to present the possibility of creating a helical surface with a circular concave profile on a CNC lathe with a universal tool: a ball-end mill cutter. In the case of the proposed processing method, the surface of the worm is shaped with a spherical-end mill cutter in many passes, and its shape depends on the setting of the tool. This machining method must be performed on CNC machines, and the tool is not geometrically related to the shape of the machined profile. The paper presents the mathematical apparatus for generating a concave helical surface. Based on the calculations, the worm was processed with a spherical-end mill on a CLX350 V4 DMG MORI turning machining center. The surface-quality analysis was carried out on a contact profilographometer, while the dimensional accuracy was verified on a coordinate-measuring machine, and the maximum tolerance field of the measurement was 13 μm. On the basis of the measurements made, the accuracy of the worm outline is consistent with the theoretical assumptions. Using the presented method of machining, we can shape helical surfaces with an assumed profile in the axial section on a CNC machine tool with the use of universal tools.

1 June 2018 in Tehnicki vjesnik - Technical Gazette
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PBPiotr Boral
Piotr Boral
ASAntun Stoić
Antun Stoić
MKMilan Kljajin
Milan Kljajin
Spur gears have a wide application in the machine-building industry. Machining process primarily selected for these gears is hobbing method with modular hobs, or with Fellows cutters. Other methods which can be applied are profiling...

4 January 2017 in MATEC Web of Conferences
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TNTadeusz Nieszporek
Tadeusz Nieszporek
PBPiotr Boral
Piotr Boral

6 May 2020 in Transactions of FAMENA
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APAndrzej Piotrowski
Andrzej Piotrowski
Rafał GOŁĘBSKIRafał GOŁĘBSKI
Rafał GOŁĘBSKI
PBPiotr Boral
Piotr Boral
The paper presents the universal mathematical model-based geometric analysis of a composite hob with replaceable sintered carbide cutting inserts. Composite hobs are characterised by lower accuracy compared to monolithic hobs and are...