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3-D computer research and comparative analysis of dynamic aspects of drum brakes and caliper disc brakes

Slavchev Y., Dimitrov L., Dimitrov Y.

Archive of Mechanical Engineering

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2018

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Vol. LXV, nr 2

253--276

EN

This paper presents the construction of adequate 3-D computer models for simulation research and analysis of dynamic aspects of caliper disc brakes, as well as of drum brakes, actuated by a short stroke electromagnet or a hydraulic thruster, when these brake types are used in the hoisting mechanism of cranes. The adequacy of the 3-D models has been conﬁrmed by comparing their simulation results with results from an experiment and from classic computation a models. The classic computational models, related to the study of main dynamic features of friction brakes, are layouts that are based on a number of assumptions, such as that the braking force instantly reaches its steady-state value, the clearance between the friction lining and the disc/drum is neglected, etc. These assumptions lead to alimitation of research options. The proposed 3-D computer models improve the research layouts by eliminating a number of the classic model assumptions. The improvements are related to the determination of the braking time, braking torque, normal force and other dynamic aspects of the brakes by performing simulations that take into account: the braking force as a function of time, the presence of clearance between the friction lining and the disc/drum, etc.

2

Influence of crane wheel defects and crane runway gaps on the dynamic response of bridge cranes during steady-state travel

Slavchev Y.

Zeszyty Naukowe Politechniki Poznańskiej. Budowa Maszyn i Zarządzanie Produkcją

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2010

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Nr 13

81-89

EN

Several 3-D computer models have been developed, using the software packages visualNastran (vN) and ANSYS, so as to investigate the influence of crane wheel defects and crane runway gaps on the dynamic response of real bridge crane structures during the steady-state travel of cranes. Well-known theoretical models have been extended by taking into account wheel elasticity, changes in travel velocity at the moment of impact etc. A numerical experiment is carried out on a real-world bridge crane model, the corresponding input data and results are provided and analyzed.

3

A research on lifting fork equipment of forklift trucks

Slavchev Y.

Zeszyty Naukowe Politechniki Poznańskiej. Budowa Maszyn i Zarządzanie Produkcją

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2009

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Nr 10

103-110

EN

This article presents a research, conducted by 3-D computer models and the finite element method (FEM), on the stressed state of fork lift arms of 12.5 kN, 20 kN and 30 kN lift capacities. The folded region of the fork has been proved as being inconsistent with the classical assumption of a curved beam of high curvature. Formulations are drawn and some suggestions are given regarding computation of parameters of that folded region.