Applied Mechanics and Materials Vol. 616

Abstract: The belonging amplitude and the phase characteristic and the transient characteristic are for K=1 and P=1 identical as for the action quantity. The core puller at pulling cores it is possible to consider as the regulation system with the force of cores pulling F₁ as the inlet quantity and the course of core movement x respectively the speed of core movement v as the outlet quantity. The equation of the regulation system is identical with the equation of regulation system obtained by a gradual integration from the measured course at pulling cores at the die cast. At application of the proportional regulator the amplitude, the phase and the transient characteristic of the action quantity and the control of the regulation circuit constructed on the basis of the transmission state that the circuit is stable a periodic. The amplitude, the phase and the transient characteristic of the regulation circuit defect constructed on the basis of the transmission state that the defect in the regulation circuit lowers relatively quickly.

Abstract: This paper deals with evaluation of n strain hardening exponent and C material constant at various velocities of the strain rate according to EN 10002-1. Dependence of tensile stress on elongation is carried out at INSTRON shredder in digital form and it is directly introduced into MATLAB working environment. To determine these material parameters suitable material models (Krupkowsky model) and MATLAB programming pack, mainly its Curve Fitting toolbox, which provides the library of standard linear, nonlinear and nonparametric models (e.g. polynomial, rational, etc.), are used. At automobile crash tests kinetic energy conversion into energy of deformation (where it is necessary to know n, C) is theoretically calculated at certain velocities so that the solid parts of the car body would be protected from damage. It would be the best to compare correctness of those calculations to the test carried out at a real model or by simulation created on the computer with necessary software equipment.

Abstract: One of a way of a material utilization of a rubber waste originated at a recyclation of tyres is its inclusion into polymeric materials. The paper describes chosen mechanical properties of an epoxy adhesive and polyurethane filled with the waste rubber. The waste rubber was gained as one of outputs of a recycling line of a firm Gumoeko, Ltd. The filler presence influences resultant mechanical properties and decreases a price of gained materials. Defining of mechanical properties enables to specify possible application areas.

Abstract: This paper deals with the up milling technology. It describes the coherencies of temperature and surface roughness achieved by this up milling process and explains the principle of up milling, briefly describes the heat generated too and shapes of chip. A main part of this paper is realization of the experiment, description of the experiment and evaluation of results shown as the resulting values of temperature and subsequent surface roughness and category of made chips. The milling is the most used technology in engineering and shape of chip is important for its transport and for economical aspect of this technology.

Abstract: This paper present problem of the examination of the parameters of cutting process on the micro-geometric and macro-geometric parameters after the turning of composite material with natural reinforcement (material is combination of two different phases the plastic matrix and wood flour). The article deals with effect of feed rate and cutting speed to roundness deviation and maximum roughness depth. The results were analyzed using device of surface roughness, roundness/cylindricity and digital microscopic camera. From the result, the surface roughness are mostly influenced by feed rate.

Abstract: In this article are compared two ways of measuring axial hole distance. The first method was implemented for measuring equipment Roudtest RA 120. The second method was implemented on the device Thome Präcision.

Abstract: Durability of cutting tools represent to a large spectral index on the basis of which is characterized by functional work. Every manufacturer of cutting tools before the actual production of these tools during the development make a tests and prescribing them characteristics on which is possible then to predict their behavior in the actual production process. It might be argued, that these information are optimized and ideal and therefore the information which producers sells by these cutting tools, do not correspond completely with their real behavior. It is necessary that information by using experiments to verify and then review their informative value and correctness. Durability of cutting tools is often indicated for one tested material of marketing aspect, which is machined and effort of user is to achieve this variable for other machined materials, then is happened problem in the production. The problem is very short lifetime of cutting tool in machining process, where the effect is impossibility to optimize the machining process. The results of this action are excesses time caused by exchanged of cutting plate and then it is make a low production of machining industry by setting of machines, and then the factory has an economical loses. This article is focused on tested of cutting tools made by sintered carbide, where the machine material is steel 100CrMn6. This type of steel is used by manufacturer of bearings, therefore the experimental part of this article should be a helper for machining manufactures, which make effectively manage with tools by optimization of cutting parameters of cutting tools and thus increase their productivity and to achieve a higher profits.

Abstract: The problem effective and economical management of the cutting tools is often the factor that manufacturing enterprises do not attach much importance. Any manufacturer of cutting tools states in promotional and marketing materials, and also in many catalogs data about cutting tools, excluding those subject know-how. Among the following data are also recommended cutting conditions and their dependent of durability of the instrument. If the company uses different cutting parameters, knows the durability of knowledge by F.W. Taylor contained in standard ISO 3685, which can be fast deduced, because dependence on cutting speed durability is in double logarithmic in shape of linear graph. What in case that this assertion was demonstrated by Taylor in 1906 was not true Durability of cutting tool would be different in that case, and it would not be possible to calculate or predict. With this knowledge about invalidity of the Taylor formula for new cutting tools pointed to science and practice by Professor Karol Vasilko, who in its publications published research results to indicate this fact. Article follows the research of Professor Vasilko and provides the opportunity to analytically derive the dependence of T-v_c for cutting materials, where Taylor's relation does not apply.

Abstract: Cutting tool durability is very important cutting tool property. Especially for cutting ceramic is necessary to define durability dependence on available set of cutting speeds and to determine lifetime of tools made of cutting ceramic. Durability of cutting tools is defined in standard ISO 3685. In standard ISO 3685 is defined T-v_c dependence for different cutting materials and standard included process evaluation of tool durability for cutting materials made of high speed steel, sintered carbide and cutting ceramic. Specification cutting tools durability made of cutting ceramic in machining process of steel 100Cr6 is very important for economics of small and medium-sized enterprises, because cutting tool durability is factor that significantly affects the budget of these enterprises. This problematic is determined for small and medium-sized manufacturers of bearings, because steel 100Cr6 is most commonly used for production of bearing rings 100 mm in diameter. This material is usable for actuator (actuators and reduction gears) too. Description of cutting ceramic durability could mean for bearings manufacturer determination of optimal cutting parameter with maximum possible use of tool lifetime. Standard ISO 3685 contains instructions how to create T-v_c dependence for cutting tools made of cutting ceramic. In this standard are only instructions how to create T-v_c dependence according to Taylor. The article compares T-v_c dependencies for various cutting ceramics (Al₂O₃, Al₂O₃+ZrO₂, Al₂O₃+TiCN) with T-v_c dependence defined in standard ISO 3685, because this standard describes T-v_c dependence for all entered cutting materials together.

Abstract: Chilled ceiling represents air-conditioning system in which a part of heat load is taken away by the ceiling thus decreasing the demand of cooling air amount. Chilled ceiling can only be applied with automatic air-conditioning control. The contribution presents computer program that can serve for either the proposal of chilled ceiling parameters or for chilled ceiling control algorithm.