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Optimal service term of the bridge cranes

Kovalenko V., Vishnevetsky S., Brewczyński D., Tora G.

Journal of KONES

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2013

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Vol. 20, No. 4

169--176

EN

The questions of the rational/optimal service term of the warehouse bridge cranes on the exploitation and projection stages are observed. The method of the residual crane resource’s definition by the criterion of the specific reduced responses is suggested. On the stage of the crane projection, the forecasting of the warehouse cranes’ resource in coordination with their constructive parameters is expedient. The existing task has main aspects: recognition of the residual crane resource and definition of the project crane resource. In course of time in the massive of the sample from the low carbon steel occur changes: grows firmness, equalize the internal tensions, little internal cracks “overgrow”, sometimes the groups of little cracks create macrocracks. This are a diffusion action. The definition of the rational constructive parameters is being carried out on the base of the work processes’ mathematical modelling. On the base of modelling is defined the size of the residual deflection of the main beam that is formed during one work crane cycle considering the action of the main beams’ free vibrations in the processes of start and braking considering the factor of the attenuation of those vibrations. In result of the modelling, we receive the microscopic size of the residual deflection, formed during one work cycle. On the base of the multisession modelling is noticed that the crane resource can be prolonged on 20-50%.

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Optimal project parameters of the bridge cranes main beams

Vishnevetsky G., Kovalenko V., Sydorenko S., Brewczyński D.

Journal of KONES

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2013

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Vol. 20, No. 3

411--417

EN

In the article are presented main principles and leads-up to the choice of the general criterion of the main beams’ optimization. The main reasons leading to the destruction of arms include cyclic load causing fatigue phenomena, creep occurrence causing elements deformation beyond a critical state, the constructions’ blistering appearing owing to the metal maturing, corrosion of the main beams’ elements, leading to the loss of their carrying capacity. The general optimization criterion is chosen. The parameters of the main beams’ endurance are defined. The device for the measuring of the size and the character of the vibrations’ decay of the bridge cranes’ main beams is suggested. We have the results of the experimental information, received on the bridge cranes of the different plants. The work directions by the optimization of the constructive parameters of the cranes’ main beams are defined. Into the suggested construction of the span beam are put such statements: high values of the general optimization criterion’s; stiffness of the arm to the reduced weight ratio, possibility of the beam’s creation of the equal resistance, minimization of the local deflection tensions from the load cart on account of the inclined walls’ position. The construction of the patented span beam of the diaphragm construction is observed and described.

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Analiza drgań suwnic pomostowych, wywołanych przerywanym ruchem ładunku

Kaliński W., Margielewicz J., Wojnarowski J.

Problemy Maszyn Roboczych

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1999

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Z. 13

15-21

PL

Wyniki monitorowania faz działania suwnic pomostowych [1, 3] potwierdziły impulsowy charakter obciążenia mechanizmów wykonawczych i ustroju nośnego. Obciążenia te są przyczyną wzbudzania drgań suwnicy, które przenoszone są na operatora. W pracy przedstawiono dyskretne modele dynamiczne drgającego układu suwnica-operator, które przedstawiono w ujęciu grafów wiązań. Zamieszczono wyniki badań analitycznych, w których uwzględniono wpływ podatności więzów na ruch układu i charakterystyki dynamiczne.

EN

Varying loading and an interrupted movement are typical for the operation of bridge cranes. Results of the computer aided investigation on time of work of bridge cranes [1, 3] verifies the impulse kind of the loading of mechanisms and crane girder. This character of the loading accounts for the vibration excitation of the bridge crane and of the operators cab. In the paper, dynamic analysis of crane lifting mechanism has been presented. There are two representations of mechanical systems transformed into bond graphs. The physical data has been foundation to numerical experiment. The dynamically characteristic of a lifting mechanism of the crane has been presented.