Defense of the dissertation of Danyarova Assiya for the degree of Doctor of Philosophy (PhD) under the educational program «8D07113 - Transport, transport technics and technologies»

L.N. Gumilyov Eurasian National University, a dissertation defense for the degree of Doctor of Philosophy (PhD) by Danyarova Assiya on the topic «Improving of the multifunctional working equipment’s efficiency of the excavator» under the educational program «8D07113 – Transport, transport technics and technologies».

The dissertation was carried out at the «Transport engineering education department» of L.N. Gumilyov Eurasian National University.

The language of defense is russian

Official reviewers:

Zhanar Zhumashevna Zhunusbekova –Associate Professor of the Department of Transport Engineering and Logistics Systems at the Abylkas Saginov Karaganda Technical University, Doctor of Philosophy (PhD), Karaganda, Kazakhstan.

Nurbol Sadykanovich Kamzanov –Head of the Educational Program “Transport Engineering” at the Kazakh National Research Technical University named after K.I. Satpayev, Doctor of Philosophy (PhD), Almaty, Kazakhstan.

Temporary members of the Dissertation Council:

Nursultan Balgaevich Zharkenov –Head of the Department of Transport Engineering and Logistics Systems at the Abylkas Saginov Karaganda Technical University, Associate Professor, Doctor of Philosophy (PhD), Karaganda, Kazakhstan.

Nurbolat Sakenovich Sembaev –Head of the Department of Transport Engineering and Logistics at Toraighyrov University, Associate Professor, Candidate of Technical Sciences, Pavlodar, Kazakhstan.

Davran Oktambaevich Radjibaev – Professor, Tashkent State Transport University, Doctor of Technical Sciences (DSc), Tashkent, Uzbekistan

Scientific advisors:

Baglan Bolsinovna Togizbayeva – Doctor of Technical Sciences, Head of the Department of Transport Engineering at the L.N. Gumilyov Eurasian National University, Professor.

Jan Vlnka – PhD, Associate Professor, Slovak University of Technology in Bratislava (Bratislava, Slovakia).

The defense will take place on June 05, 2026, at 03:00 PM in the Dissertation Council for the training direction «8D071 – Engineering and engineering trades» under the educational program «8D07113 – Transport, transport technics and technologies» of L.N. Gumilyov Eurasian National University. The dissertation council meeting will be held offline and online.

Link: https://teams.microsoft.com/meet/42344932398024?p=4RRzA32TugubMzGqat 

Address: 2 K. Satpayev Street, Room 302, Astana

Abstract (English): ANNOTATION of the dissertation work by Danyarova Assiya Samatovna "Improving the Efficiency of a Multifunctional Working Element of an Excavator" submitted for the degree of Doctor of Philosophy (PhD) in the educational program "8D07113 – Transport, Transport Equipment and Technology" Purpose of the dissertation research. The development of a scientifically based design methodology and the creation of a sequential combined mechanism for medium-tonnage excavators, providing an optimal combination of attachment changeover speed, operational safety, and high maintainability. The proposed technical solution ensures an even distribution of the force flow across the working surfaces, which eliminates stress concentration and qualitatively increases the bearing capacity of the joint. The study has convincingly demonstrated that the key disadvantage of most existing analogues is the dependence of fixation on continuous pressure maintenance in the hydraulic system, i.e., the use of the principle of active safety. As a conceptual solution underlying the present work, a transition to passive safety, implemented through geometric self-locking of the worm pair, is proposed. This approach constitutes the key idea of the dissertation research. Research objectives: 1. Review of existing systems: Identification of key technical and operational limitations in existing solutions for rapid dismantling. 2. Determination of operational loads: Determining the load model, from normal working loads to peak digging loads. 3. Development of a new kinematic scheme: Design and justification of an integrated combined mechanism for linear movement. 4. Kinematic study and trajectory verification: Demonstration of precise rectilinear movement of the slides in reverse direction. 5. Strength assessment of critical parts: Calculation of stresses, safety factors, and material selection for the slider assembly. 6. Computer verification: Verification of results using the Finite Element Method (FEA) in SOLIDWORKS Simulation (stress and strain graphs). 7. Comparison and conclusions: Evaluation of the functionality and reliability of the structure by comparing theoretical and simulation data. Research methods. The work employs a set of methods including: theoretical mechanics, strength of materials, theory of machines and mechanisms, mathematical modeling, finite element method (FEM), and experimental research. Main provisions submitted for defense: 1. Kinematic scheme of the combined mechanism. A kinematic scheme of a combined mechanism (worm + crank-connecting rod transmissions) has been developed. 2. Mathematical model and methodology for calculating the clamping force and self-locking conditions. 3. Results of experimental studies confirming the compliance of the prototype with the calculated characteristics. Description of the main research results: 1. A kinematic scheme of a combined mechanism (worm + crank-connecting rod transmissions) has been developed. A combination of a worm drive and a symmetrical crank-connecting rod mechanism is used to drive the QCH (quick-change mechanism), guaranteeing strictly rectilinear, opposite movement of the slides without misalignment. 2. A mathematical model has been developed that considers the combined operation of the hydraulic drive and the mechanical locking system under dynamic loading. 3. Comprehensive strength analysis methodology. A two-stage strength analysis method (analytical calculation + CAE simulation) has been developed and validated, allowing accurate determination of safety margins and optimization of the slide design. Justification of the novelty and importance of the obtained results. The scientific novelty lies in the development of a new quick-change mechanism with a sequential combined scheme that ensures uniform distribution of the force flow across the working surfaces, eliminating stress concentration and qualitatively increasing the load-bearing capacity of the connection. The practical importance of the research is confirmed by the fact that the proposed QCM (quick-change mechanism) will directly eliminate the identified shortcomings of existing systems, lead to a reduction in the time needed to replace attachments, increase operator safety and make the machine more versatile on construction sites. The presence of implementation acts confirms that the research results have been brought to the stage of practical implementation, which is an absolute advantage of the work. Compliance with scientific development directions or state programs. Strengthening Kazakhstan's transit potential fully aligns with key state programs: "Nurly Zhol", the National Development Plan until 2029, and the Strategic Development Plan of the Republic of Kazakhstan, as well as with scientific priorities in the field of digitalization (a digital transit corridor with localized mechanical engineering and road construction support), which directly supports the implementation of the Comprehensive Mechanical Engineering Development Plan for 2024–2028. Description of the Applicant's Contribution to the Preparation of Each Publication The applicant is the developer and author of all the works listed below, having made a substantial contribution to the publication of scientific works related to the dissertation. Each article is a conclusion derived from the chapters of the scientific dissertation. 1. Togizbayeva, B., Sherov, K., Danyarova, A., et al. (2023). Review of the developed systems of a quick-release device for a hydraulic excavator. Bulletin of the L.N. Gumilyov Eurasian National University, 143(2), 193-203. 2. Danyarova, A.S., Togizbayeva, B.B., Sazambayeva, B.T., et al. (2024). Evaluation of the effectiveness of quick-release mechanism designs for excavator buckets: a comparative study. Science and Technology of Kazakhstan, (2), 253-261. 3. Danyarova, A.S., Navikhan, B., & Kenesbek, I.B. (2024). Development and design of the assembly process. In Proceedings of the 12th International Scientific and Practical Conference "Actual problems of transport and energy: ways of their innovative solutions" (pp. 311-316). Astana. 4. Danyarova, A., Togizbayeva, B., Balabekova, K., et al. (2023). The choice of a method for calculating the digging forces and loads acting on the elements of the working equipment of a hydraulic excavator. Bulletin of the L.N. Gumilyov Eurasian National University, 145(4), 188-203. 5. Danyarova, A., Togizbayeva, B., et al. (2025). Investigation of Strength and Calculation of Wear Resistance of A Quick-Release Mechanism in Connection With The Working Attachment of A Hydraulic Excavator. Strojnícky časopis, 75(1), 9-16. 6. Danyarova, A.S., Alas, A.Zh., Togizbayeva, B.B., et al. (2024). Mechanical quick-change device for an excavator (Patent No. 9769 RK). Published September 10, 2024. 7. Danyarova, A.S., Alas, A.Zh., Togizbayeva, B.B., et al. (2024). Hydraulic quick-change system for an excavator (Patent No. 37648 RK). Published October 30, 2024. 8. Danyarova, A.S. (2025). Substantiation of the effectiveness of the developed hydraulic quick-release excavator mechanism. In International Scientific and Practical Conference "Development of the machine-building industry and training of highly qualified personnel of a new formation" (pp. 43-45). Astana. It should be noted that based on the results of the research, an invention was developed that received a positive Qazpatent expert opinion. The analysis showed that the claimed hydraulic quick-change system for the excavator meets the conditions of patentability, namely the criteria of "industrial applicability", "novelty" and "inventive level". A patent for an invention has been obtained. Dissertation content. The dissertation consists of an introduction, five chapters, and a conclusion, and is presented on 123 pages including an appendix (4 pages). It contains a list of references of 96 sources, includes 15 tables and 59 figures.

Dissertation

List of Scientific Works

Consultant's Review

Foreign Consultant's Review

Conclusion of the Research Ethics Committee