On the question of the creation of promising hoisting cranes

Sazambaeva B.T., Sarguzhin M.H., Beisenova A.S., Zhanabay A.G.

Kazakh National Technical University after named K.I.Satpayeva

Kazakhstan

Turdaliev A.T., Sazambaeva B.T., Sargozhin M.H., Zhanabay A.G.

In work the is intense-deformed condition of a flying beam of the bridge crane is shown. The technique durability calculation of the bridge of the crane includes: solid-state modelling for definition of the is intense-deformed condition of the bridge of the crane by a method of final elements.

Crane-structural industry of Republic of Kazakhstan, in compare with the Europe, was and remains focused to get the fabricated parts and mainly to satisfy with the domestic needs of intensively working industry. Therefore, the main direction in elaboration and manufacturing of bridge cranes is the maximum provision with the secure exploitation reliability and durability. It causes the calculation of cranes steel structures.

In the sphere of hoisting machinery of RK is the issue of decreasing of metal content constructions of hoisting cranes. The weight saving of created cranes can be conducted in the following ways:

· by optimization of constructive decisions.

· by using of high quality steel structures

· by the reasonable calculated criteria of bearing capacity of cranes structures and its differentiation.

Further improving of hoisting cranes constructions can be achieved with the method calculation of improving by bearing capacity, durability, security with the dynamic effects of loading.

The creation of perspective constructions of hoisting cranes requires analysis and exchanging of experience of investigation, constructing, manufacturing and exploitation of bridge cranes with the aim of establishing of national and international trends in this machinery sphere, deeply studying of information as per its constructions and parameters, that will help the constructors and designers to focus on this created projecting system of bridge cranes in the world.

Due to it, in many cases, in problems solving of dynamic of elastic system with the distributed parameters is widely using the methods of leading them to the concentrated mass, which allows to use their simplified dynamic models during calculation and steel structures investigation, and that’s why the most important characteristic of dynamic models of steel structures are: mass, rigidity, frequency and natural oscillation period.

The preliminary, right choice of constructive schemes and cross sections of steel structures elements and calculation by using of modern programmes during the exploitation process of hoist cranes provide the stability, rigidity and durability.

In this work it’s showing the calculations of beam with the bending moments and reactions in supports. For programme creation it was used the object-oriented model of software components – Delphi language and connection with the object model AutoCad, solid Work. Delphi allows fully to integrate the designing with the COM objects. Architecture support CORBA (Common Object Request Broker Architecture) opens in front of the applications created in Delphi for intel platforms (Windows + Intel), the world of other operating systems (UNIX, OS/2, WMS). The developed software takes into consideration the bending moments and reactions, also automatically gives the corresponding formula by pressing “calculation” in the main page, picture 1.

Picture 1 – Definition of twisting and bending moment of main girder of bridge crane

For consideration of stress-strain status in complex loading of span beams (tension – compression, bending and torsion) except the usual geometric characteristic, its crossings and given powers it’s necessary to determine some additional geometric characteristics of crossings and the power factors were used Solid Work.

Having the conditions of fastening an loading of span beams of box section of given longitude and lateral powers, that applied to the current case 1, warping section will be different, that will give the appearance of additional, normal and concerned stress of crossings, that could be achieved the volumes comparable with the main bending stress. By load factor changing and trolley moving we receive the loading of span beam, when the trolley is in the medium part, in the picture 2 shows the stress-strain status of span construction (box section) of bridge crane with 16T loading and span length 16,5m, uplifting speed 0,14 m/c, trolley moving speed 0.71 m/c. type of crane rail RP-50. From the pictures we see that the medium part of the bridge under the trolley is the more loaded. The constructed model of bridge crane is loaded with the different capacity from 3.2t to 16t. After, the model is created and it is entered all necessary corrections, it was done the following actions: the first – fastening of the model, model dividing in the final elements, the step of dividing is 200mm and after going to APM structure 3D, where with it calculates; the second – gives the appropriate loading: the weight of trolley with uplifting mechanism, moving, (in the scheme shows the trolley without mechanisms, but the weight of these mechanisms is taken into consideration); estimates its stress-strain status. Loading map allows to analyze the distribution of different internal reacted power factors (forces and moments) during model construction elements using by the dialogue settings, can be checking the results of components and normal stressing in the plane of axes X and Y of local system of construction coordinates. From the picture 2 it’s seen, that the medium part of bridge under the trolley is more loaded.

Picture 2 – Map of equivalent stress model of the transit beam bridge crane when the truck in the middle of the bridge

The conclusions:

· The right choice of constructive schemes and sections of steel structures elements, calculation by using of modern programmes during hosting machines exploitations provides them with the stability, rigidity and durability.

· The strain stress status in the complex loading of span beam of hoisting machines (tension-compression, bending and torsion) can be determined by the method of final elements with the using of modern programmes.

· The map of equivalent stressing of model construction allows determining the more loaded parts of constructions.

REFERENCES:

1. Vershinsky A.V. «Manufacturability and bearing capacity crane metallic» - M.: Mawinostroenie, 1984.167 paper.

2. Alexandrov M.P., Gohberg M.M. « Reference cranes, Volume 1, 2» - L: Mawinostroenie, 1988.