The paper discusses the use of efficient surfaces for heat transfer enhancement during a nucleate boiling heat transfer. Distilled water under ambient pressure was the working fluid in the presented experiment. The application of a brass mesh of 0.63 mm aperture and 0.20 mm wire diameter on the surface of a copper heater led to considerable improvement in the value of heat flux at low temperature differences of a few Kelvin, where the enhancement ratio exceeded 2. Such modified surfaces could be used in the design of more efficient heatn exchangers e.g. in refrigeration systems.

The article presents preliminary fatigue test results of selected grades of constructional steel used for producing elements of semitrailers and trailers, which are made by WIELTON S.A. company. Demand for fatigue tests of fine-grained steel has been reported by designers looking for new applications of high strength steel in new constructions. Fractorapnic analysis of the selected elements proved strong relation between fatigue structure and microstructure of the materials.

This paper treats a variational iteration technique, which is based on variational iteration method, for solving linear and non – linear two – point boundary value problems in the form of a fourth – order differential equation and five boundary conditions. The solution of this problem is possible only when the considered equation includes an unknown parameter. The presented method has been illustrated with a numerical example.

The paper summarizes the results of observation and quantitative analysis of porosity in IN713C superalloy in as-cast and after the creep test. The sources of porosity in castings are shortly described and the methodology of pores measurement is circumscribed. The results of pores in as-cast and after the creep test were shown and, finally, the interpretation of the result was presented.

The article analyzed the problem of cloud defect in metallic paint, caused by grain arrangement during paint application on a structural element. Presents test results of coating system consist of a high solid corrosion protection primer and a two-component topcoat with a metallic gloss effect (RAL 9006) developed in our company. The paint system properties were examined after the conditioning period.

Most of the products available on the market are sold together with different types of packaging. Information about the product, manufacturers etc., is placed on these packages but their main function is to protect the product during transport. After the product is removed, the packaging becomes waste which, according to Polish law, should be managed in an appropriate way. Recycling and recovery of the material are the most important issues. Basic statistics on recycling of packaging waste showed that paper, cardboard and aluminum packaging are recycled to the greatest extent in Poland. In the article, definitions of packaging and packaging waste according to Polish law are presented, together with legal acts on waste management. The main statistics connected with the management of packaging waste are also presented.

Quantitative microstructure characterization is currently required in R&D as well as in routine quality control of materials and products. Every step: preparation of the laboratory and specimens, measurements and interpretation of the results etc. can be a source of serious errors. Application of the ASTM guidelines can minimize these problems and improve international circulation of the results. The paper characterizes selected ASTM standards devoted to laboratory practice and analyses the complexity of microstructural materials characterization.

This paper discusses the effect of selected parameters of laser welding on mechanical properties of welds. Two parameters were analysed: the welding speed and the laser power. The properties of the material in the fusion zone and the heat affected zone were determined by hardness tests and microscopic analysis. The results indicate welds produced at different welding parameters have similar properties.

Cleaner production is a management strategy aimed at reducing the losses associated with waste of energy and raw materials which focuses on waste prevention and not the way of its utilization. Cleaner Production can also reduce company’s costs incurred during the processes taking place within the organization. In the case of companies involved in wood processing (sawmills, carpenters, etc.)a lot of waste in the form of sawdust, shavings or edgings is created. These are materials that can be used as an alternative fuel for firing furnaces and boilers. Good sales management of this type of waste after production allows companies to obtain additional income and minimize environmental risks.

Diversification strategy is currently used by enterprises to increase their stability and economic condition. It is not easy to realize the measurement of the process. The application of the parameter of entropy, which is well-known is physics, is one idea of parametrization. In the machinery industry, product diversification is connected with different consumers representing factories from different machinery sectors: mining, steel, building, agricultural and food. The possibility of estimation of the production diversification in the machinery industry by the application of the entropy-based parameters is discussed in the paper.

This paper describes a part of research related to the elimination of adverse phenomenon involving the occurrence of a negative oxygen balance of combustion products of missile engines during their firing from aircrafts. It also presents the results of comparative tests of rocket engines equipped with an additional oxidizer charge.

Basic requirements for modern machine elements include the improvement of durability alongside the reduction of the cost of materials. This entails the need for the manufacturing process to ensure a stable geometric form of those elements. This analysis aims at developing loading schemes for the dynamic stabilization stand designed for the straightening of the discs buckled as a result of hardening heat treatment [1, 2].

The paper presents models for designing of information systems for manufacturing. Chosen model of system implementation has a significant impact on the quality and performance of the target solution. Special focus is on the data model layer and the possibility of changing the standard three-tiered model of information systems through increased utilisation of resources of database server.

This article analyzes screw connection of slewing bearings to various structures of support elements. The susceptibility of support elements to the load distribution in particular bearing screws was examined by means of the Finite Element Method. The load values of screws and their distribution around the perimeter of the combined bearing rings were also specified.

Shainin’s approach is a specific sequential heuristic aimed at finding and ranking the most important factors which impact the investigated process. The sequential aspect of the approach is simultaneously its strongest and weakest side, because just after detection of the most important factor, the further analysis is stopped without any additional cost. However, such a detection may take place at the end of the whole sequence. This paper tries to answer the question if the dominant factor may be hidden by interactions with other factors.

This paper presents the modelling of a direct acting relief valve with the use of the new approach of CFD techniques which uses the Lattice Boltzman Method (LBM). It allows for eliminating the biggest problem that occurs during the simulation of a valve operation, which is the motion of a working component. During traditional CFD modeling, a deformed mesh has to be used in such a case, which may lead to the occurrence of computational cells with negative volume and, as a consequence, remeshing of fluid domain.

McKibben pneumatic artificial muscles (PAMs) allow for a proper representation of static and dynamic movement characteristics of biomechanical systems. These actuators have features similar to physiological muscles such as ability to generate high value of force in short time and elastic and damping properties. McKibben muscles have a nonlinear character – the value of a generated force depends not only on the pressure but also on the stroke. In the presented paper, the authors exemplify basic traits of these actuators and present drawn characteristics of a force to stroke at a constant pressure.

The paper is concerned with the performance properties of electro-spark deposited coatings. The properties were assessed by analyzing the coating microstructure, X-ray diffraction, microgeometry, microhardness, and corrosion tests. The studies were conducted using WC-Co-Al2O3 electrodes produced by the sintering of powders. The anti-wear coatings were electrospark deposited over C45 carbon steel by means of an EIL-8A. These coatings are likely to be applied in sliding friction pairs and as protective coatings.

The well-known statistical tests have been developed on the basis of many additional assumptions, among which the normality of a data source distribution is one of the most important. The outcome of a test is a p-value which may is interpreted as an estimation of a risk for a false negative decision i.e. it is an answer to the question “how much do I risk if I deny?”. This risk estimation is a base for a decision (after comparing with a significance level α): reject or not. This sharp trigger – p-level greater than α or not – ignores the fact that a context is rather smooth and evolves from “may be” through “rather not” to “certainly not”. An alternative option for such assessments is proposed by a fuzzy statistics, particularly by Buckley’s approach. The fuzzy approach introduces a better scale for expressing decision uncertainty. This paper compares three approaches: a classic one based on a normality assumption, Buckley’s theoretical one and a bootstrap-based one