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DOI: https://doi.org/10.37129/2313-7509.2024.21.163-172

TECHNOLOGY OF RESTORATION OF CRANKSHAFTS OF DIESEL ENGINES WITH NECK STRENGTHENING

Abstract

The aim of the work is to explore reserves for increasing the durability of automobile engines, restoring engine components to their operational condition. The object of the study is to justify technological methods for enhancing the longevity of basic components of diesel engines, as well as methods for predicting their durability. The reserve for increasing the efficiency of operation and repair of machinery, saving production resources, lies in the restoration of worn-out parts of automobile engines, particularly pistons. An analysis of defects in various domestic and foreign cylinder blocks (CB), cylinder head blocks (CHB), and crankshafts (CS) revealed up to 10...15 defects of the following types on each of them: gas erosion of the mating surface, scoring on the CB bearing surfaces, scoring and scratches on CHB. The most widely used methods for obtaining repair blanks are welding (60-80%) and thermal spraying (6-12%). The wear resistance and fatigue strength of deposited coatings can be significantly increased using tooling that forms a favorable texture of the coating. Increasing wear resistance through the deposition of high-carbon alloyed material leads to a decrease in the fatigue limit of restored parts. Technologies for restoring resource-forming engine elements by electroplating iron-nickel coatings under conditions of controlled electrolyte depletion above the electrolyte mirror have been improved, allowing for uniform coating deposition with less allowance for mechanical processing and homogeneous physico-mechanical properties.

Keywords: neck, technology, crankshaft, strengthening, modification. durability.

FULL TEXT (in Ukrainian)

References

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The article was submitted 26.03.2023.