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The analysis of boring process of automatic horizontal boring machine
Šohajek, Jiří ; Roubíček, Jiří (referee) ; Bradáč, František (advisor)
The object of this dissertation is to analyse a drilling process of an automatic horizontal boring machine the SVD2 for drilling of bearing holes. There were problems with vibrations during drilling process, causing an extreme noise and this dissertation solves them. First of all it was necessary to analyse the vibrations, to examine a machining process and measure machine dynamics and statics. Another task was to compare measured results with mathematical models and after their analysis to design structural and other solutions. The SVD2 machine was designed on the basis of a previous type the SVD. Its conversion to a new one was based on adding of six spindles. As a result a number of drilled bodies was increased from one to four, so a performance was increased four times. That is why there was an original intention to rebuilt the other two spindle machines. To leave the basical parts of the machine without any modification ( such as a reinforcement of a mount and adjusting of a bigger distance of a side linear spindle guideway and a cross linear guideway of a support for clamping devices), would be unsuitable solution, which was confirmed after a measurement and a following analysis.
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Modelling of damping devices in interaction with a structure
Kalina, Martin ; Lehký, David (referee) ; Frantík, Petr (advisor)
The aim of my master’s thesis was to create models of the damping device and observing their behavior in interaction with the structure. First was the construction separately modeled with Java application named FyDiK2D like a model with one degree of freedom. Model of construction takes form like a high, thin rod with full circular cross section. The lower part was restrained into the subsoil. The design was to verify the correct functionality of the model by comparing the analytical and numerical solutions. For capturing the precise behavior of the structure was converted to a multi-stage model. Then the pendulum damper was applied on this construction and found amplitude lies in highest point of multi-stage model. He was then replaced by tuned mass damper. By comparing these amplitudes from both dampers was found which kind of damper is efficient for multi-stage model.
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Stiffness characteristic of front part of the vehicle
Coufal, Tomáš
So far, in the field of forensic engineering was used to describe the stiffness of the front part of the vehicle only central stiffness characteristic that can be used with sufficient accuracy for frontal crash with a full overlap. However, if the vehicle crashes with only partial overlap so can be central stiffness characteristic limitations in the accuracy of the calculation of the deformation energy. The present article deals with the stiffness of the each parts of the front part of the vehicle for their use in forensic expert practice. Stiffness characteristics was processed for each part of the vehicle, with which you can calculate the exact deformation energy for a specific front part of the vehicle which was damaged in a frontal collision.
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Radial gantry crane
Dvořák, Milan ; Pokorný, Přemysl (referee) ; Malášek, Jiří (advisor)
The goal of this Bachelor’s Project is to develop a structural design of special construction of Radial Gantry Crane by entered parameters, it will be used in enclosed space to manipulation with various materials. The structural design will be done by basic set parameters, which as geometrically, so statically they declare workspace in industrial hall or industrial workshop and subsequent manipulation of worker with a construction crane during operation. As each design of machines, so and structural design of Radial Gantry Crane is based on the strenght design calculations, from which follows the choise of suitable material, which declares the cost of production and operation of Radial Gantry Crane. Special attention will be given to alternative designs mobile supports, whose basic parameters such as stiffness, weight and shape determine the size of the frictional forces between the wheels and the floor rails mobile workspace, implying stress of the whole structure Radial Gantry Crane when operating in loaded condition.
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Resistance of the roof structure loaded with photovoltaic panels
Holoubek, Jan ; Bažant,, Zdeněk (referee) ; Strnad, Jiří (advisor)
The aim of the thesis is to verify the resistance of the roof structure loaded with photovoltaic panels. On the roof of industrial building of rectangular plan with dimensions of 26,5 x 24,5 m in Hlinsko, the investor decided to install photovoltaic panels. Preliminary diagnostic survey showed only flexural reinforcement in the field of all considered load-bearing elements. Bending strength was assessed by these structural elements: reinforced concrete slab, reinforced concrete beam, reinforced concrete grinder. Static calculation includes a minimum reinforcement of support and necessary shear reinforcement, which must be demonstrated by a detailed diagnostic survey. The structural analysis includes the assessment of reinforced concrete beam deflection after loading. All assessments were performed according to currently valid Eurocodes. The calculation showed that all supporting elements meet the bending resistance and deflection of the beam is smaller than the limit value laid down in the EC, so the roof of the hall can be loaded with photovoltaic panels.
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Processing technology and quality of meat smoked mackerel
KÖLBL, Antonín
The technological process of smoked mackerel (Scomber scombrus) manufacture was described in detail with a focus on quality of muscle. The smoked mackerel brined in 6%, 12% and 15% of brine was monitored by texture profile analysis (TPA) using a cylindrical probe P 75 and spherical probe P 1S. Textural properties of muscle, such as hardness, cohesiveness, springiness and chewiness were evaluated. With increasing concentrations of brine muscle hardness and chewiness significantly decreases. In texture measuring, using a cylindrical probe P 75, in 6% of brine approximately 10.4 % higher hardness can be achieved, about 1 % higher chewiness and about approximately 5 % lower springiness expect, than when brined in 12% of brine. When brined in 15% of brine about 6.7 % lower hardness, about approximately 11.2 % lower chewiness and about 6.5 % lower springiness expect, than when brined in 12% of brine. When using a spherical probe P 1S is at brined in 6% of brine about approximately 6.5 % higher hardness and about approximately 11 % lower chewiness that brined in 12% of brine. When brined in 15% of brine about approximately 13 % lower springiness and approximately 21.7 % lower chewiness expect, than when brined in 12% of brine. To a lesser extent springiness was influenced, cohesiveness with increasing concentrations of salt in brine was unchanged. Texture measurements were supplemented by microbiological analysis of the total count of microorganisms (TCM). This analysis confirmed that with increasing concentrations of salt brine the count of microorganisms decreases (on 103 using 6% of brine and on 102 using 12% and 15% of brine) as a result of reduced water activity (aw).
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