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Abstract

The article presents results of research concerning identification of organization schemes and management processes that make a small construction company function efficiently and hold against other entities in local markets. It was estimated to what extent the classic principles for organization and management are realized in a small construction company. Basic for that evaluation were the Toyota management principles and the HR organization principles as gathered and quoted by Rowiński. The research was conducted with the guided interview method, supplemented by CAWI (Computer-Assisted Web Interview) survey. Based on the information gathered the characteristics of organization and management of small construction companies active in the business of finishing works were described. The most important elements presented were the owner-employee relations, scope of activities performed personally by the owner, quality assurance methods for works, scope of cooperation with other entities, mode of customer acquisition and ways in which new technologies are adopted. It was found that there is large coincidence between organizational and management principles applied in researched companies, and the rules for the Toyota manufacturing processes, slightly lower coincidence was found in case of analysis of the rules quoted by Rowiński. The research has shown the large universality of the rules found in literature – these are largely accomplished, even without owners and employees having the knowledge about their exact reading.

Abstract

Austenitic stainless steels are materials, that are widely used in various fields of industry, architecture and biomedicine. Their specific composition of alloying elements has got influence on their deformation behavior. The main goal of this study was evaluation of magnetic properties of selected steels, caused by plastic deformation. The samples were heat treated in different intervals of temperature before measuring. Then the magnetic properties were measured on device designed for measuring of magnetism. From tested specimens, only AISI 304 confirmed effect of plastic deformation on the magnetic properties. Magnetic properties changed with increasing temperature.

Abstract

The present contribution deals with the influence of tribological conditions on coating quality. Two types of coatings were selected for analysis WC-WB-CO and WC-FeCrAl, to advise that a new type of coating - carbide green. These coatings were applied to the base material AISI 316L of technology HVOF – High velocity oxygen fuel. The aim of the experimental study was to determine the quality coatings and its resistance to abrasive wear, depending on the number of thermal cycles. It was evaluated hardness, thickness, the resistance to abrasive wear in free abrasives and firmly bonded abrasives. Results of experiments showed a higher resistance of the coating WC-Co-WB.

Abstract

Adhesive bonding is one of the simplest and most common methods used for joining materials. It is applied in both production and repair works. The most commonly used adhesives are cyanoacrylates, due to the possibility of combining various materials and short curing time. One of the ways to assess the quality of the adhesive used is testing the shear strength of bonded joints. Three adhesives commonly available on the Polish market, from various manufacturers and with different prices per gram of product were tested. The polymer materials bonded were poly(methyl methacrylate) and polycabonate, since they are broadly used in the automotive industry and household equipment. The study revealed significant differences in bonding strength, reaching as much as 38% The adhesive’s price was not commensurate with the quality of the product tested in all cases.

Abstract

The article is devoted to the overall view of experimental research of reinforced concrete beams with the simultaneous influence of the corrosion environment and loading. The tests have been carried out upon the reinforced concrete specimens considering the corrosion in the acid environment, namely 10 % H2SO4 that have been taken as a model of the aggressive environment. The beams are with span equalling to 1,9m with different series of tensile armature, concrete compressive strength and different length of impact of corrosion (continuous and local). The influence of simultaneous action of the aggressive environment and loading on strength of reinforced-concrete beams has been described. For a detailed study of the effect of individual components there was suggested additional experimental modelling of the only tensile armature damage without concrete damage. It will investigate the influence of this factor irrespective of the concrete.

Abstract

The following article discusses the problem of durability of girders made of structural steel S355 affected by corrosion. It presents the Polish procedure for calculating the time between failures of steel elements of bridge and durability factors necessary to estimate the impact of corrosion on the durability of steel road bridges. According to the presented procedure, two real bridges of steel structure were analysed. The bridges selected for analysis are located in extremely different corrosive environments in Poland. This bridges were built in different areas of the country which are characterized by different (mountain, urban) aggressiveness of the environment. The objects of the analysis differ in terms of corrosion type occurring on the bearing system. Their age is also different which has a significant impact on their safety.The results obtained allowed to determine the time when, with the existing corrosion damage, failures may occur.

Abstract

The paper presents a case study of the practical use of Deming cycle in a manufacturing company, from the plastics processing industry, from the sector of small and medium-sized enterprises. The paper is a study of literature in the field of continuous improvement and characterized by a cycle of continuous improvement, called the Deming cycle, or PDCA cycle. This cycle was used as a solution to quality problems which occurred during production of photo frames: discolorations and scorches on the surface of the frame. When measures were introduced to reduce the number of nonconformities, a decrease by more than 60% was observed.

Abstract

New challenges for the Aluminium alloys used for the production of castings for automotive engine components result from an evolutionary trend of internal combustion engines towards higher specific power output. Cylinder heads, in particular, have to withstand higher operating temperature and stress levels. Present work describes quality control of microstructure (Si-morphologhy and Si-size) and mechanical properties (UTS, elongation, Brinell hardness) of cylinder head casting as effect of different T6 heat treatment (solution heat treatment time - 2, 3, 4, 5, 6, 7 hours). The data obtained from this study will be used to improve process control, and to help the selection of heat treatment of the casting for future products.

Abstract

Rational and efficient use of thermal energy in recent years has resulted in significant changes in the heating system as well as technological progress. In order to design a heating system properly and exploit it correctly, an in-depth understanding of the hydraulic issues is necessary. Application of automatic control system in various sectors of heating network has resulted in a more dynamic and efficient work of the whole system. For proper operation of a thermal system it is also necessary to compile a correct heat balance and a regulation graph that allows to determine the optimal mass and parameters of heat medium. The article discusses the problems of supplying heat process, types of thermal systems and selected problems of hydraulic issues that occur in the heating networks.