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Abstract

Aluminium, titanium, and nickel base alloys are mostly and widely used for aircraft jet engine construction. A proper evaluation of its microstructure is important from working safety point of view. To receive a well prepared sample of microstructure, some important steps have to be undertaken. Except for proper grinding and polishing of a sample, structure developing is a significant step, too. In order to develop microstructure various chemical reagents were used to achieve the best results for microstructure evaluation. The chemical reagents were used according to the previous knowledge and some new ones were also tested. Aluminium AK4-1č, titanium VT – 8, and nickel VŽL – 14 and ŽS6 – U alloys were used as an experimental materials. Alloy AK4-1č is used for fan blade production with working temperatures up to 300°C. It is a forged piece of metal machined down into final shape by five-axe milling machine. Alloy VT – 8 is used for high pressure compressor rotor blade production with working temperatures up to 500°C. Blades are forged as well and finally grinded. Finally nickel base alloys VŽL – 14 and ŽS6 – U are used for turbine blade production with working temperatures up 950°C. Blades for turbine are casted into mould with reducible models.

Abstract

The paper presents the results of low and high frequency fatigue tests carried out on nodular cast iron. The specimens of synthetic nodular cast irons from three different melts were studied in the high cycle fatigue region (from 105 to 108 cycles) using fatigue experimental equipments for low and high frequency cyclic loading. Low frequency fatigue tests were carried out at frequency f ≈ 120 Hz using the fatigue experimental machine Zwick/Roell Amsler 150HFP 5100; high frequency fatigue tests were carried out at frequency f ≈ 20 kHz using the ultrasonic fatigue testing device KAUP-ZU. Both fatigue tests were realised at sinusoidal cyclic push-pull loading (stress ratio R = −1) at ambient temperature (T = 20 ± 5 °C).

Abstract

According to research, metal processing industry has the highest risk of accidents at work, due to the necessity for personal protective equipment use and strict execution of safety rules and procedures. The paper presents the individual characteristics of health and safety management in the company producing steel flat bars. Special attention has been paid to the safety aspect of the use of automated logistical equipment (gantries, automatics) that increase the risk of work-related accidents. The results of research on the difficulties resulting from the specifics of production (metallurgical industry) has been presented.

Abstract

The paper presents the results of research carried out in one of the domestic companies producing rubber and plastics products for the automotive industry. The results of the evaluation of the quality control function during production of the low pressure hoses and the characteristics of the main machine taking part in this production process are presented. An analysis of the results of the evaluation of factors influencing the quality of production is presented and guidelines for improving this production process are presented. One of the proposed solutions for improvement is the modernization of the machine park and introduction of production nests.

Abstract

Age-hardening provides one of the most widely used mechanisms for the strengthening of aluminum alloys. The age-hardening involves three steps: solution treatment, quenching and aging. The temperature of solution treatment and aging is very important in order to reach desired properties of castings. The optimum temperature of solution treatment and aging led to formation microstructural features in form which does not lead to decreasing properties, but increasing ones. The major micro-structural features in A 226 cast alloys which are responsible for increasing properties are: eutectic Si particles, Cu-rich phases, Fe-rich phases and porosity. The increase of properties depends on morphology, size and volume of microstructural features. In order to assess age-hardening influence on microstructural features in A226 cast alloys were used as possibilities of evaluation by means of image analysis. Quantitative analysis decelerate changes in microstructure includes the spheroidization and coarsening of eutectic silicon, gradual disintegration, shortening and thinning of Fe-rich intermetallic phases, the dissolution of precipitates and the precipitation of finer hardening phase (Al2Cu) further increase in the hardness and tensile strength in the alloy. Changes of mechanical properties were measured in line with STN EN ISO.

Abstract

Health and safety at work issue concerns every employer. Adjusting the work environment to legal requirements and standards is the key to creating health and safety culture. In every functioning OSH system there are various types of problems that employers face. The subject of the article is how to solve the problem of safety in production systems using the brainstorming method. The basic element of creating health and safety culture is an appropriate approach to occupational risk management. Risk assessment in the workplace should take place in teams as it is possible to reliably identify hazards and accurately assess them.

Abstract

Neodymium magnets currently dominate the magnet market due to their superior magnetic properties with maximum volume minimization. In this paper, the results of X-ray analysis for two types of magnetic powder obtained from the recovered magnets traditionally used in electric motors and hard disk have been presented. The NdFeB magnets are composed of 25-35 wt. % rare earth elements (RE) and the rest being transition metals (mainly Fe.). RE, other than Nd, such Dy, Pr, Tb and Gd or exogen elements, other than Fe, such as Al, Co, Ga, Nb, Si, Cu and Zr can also be present as minor admixtures. This paper brings an opportunity to introduce the hard magnets recycling technology on an industrial scale.

Abstract

In the paper, the method of the production process improvement with the use of lean production tools has been presented. The Value Stream Mapping (VSM) for the cardboard packaging production process has been presented. On the basis of the current state map (CSM), areas for improvement have been designated – 5 organizational changes of the process were marked out. To minimize the three basic losses excessive storage, unnecessary movement and delays, the changes were introduced in the method of inter-operative transport, supervision of the storage condition (input and output of the process), control at the processing operation and the use of a production loop. As a result of the changes, it is possible to shorten the process time, shorten the total time of operations adding value and reduce the number of non-compliant products.

Abstract

The article presents the results of risk analysis associated with nonconformities of aluminium profiles in the process of coating and quality inspection methods used to their detection. Analysis of risk was done based on results of FMEA method. Evaluated quality inspection methods were distinguished based on the term of inspection in the ISO 9000:2005 norm. Manufacturing process of aluminium profile in micro-technological approach was presented. Triple quantification of nonconformities risk based on the FMEA method by using three different approaches was conducted. Analysis of nonconformities risks associated with the use of specific quality inspection methods was done. In the last part the analysis of causes of critical nonconformities, proposals for improvement actions reducing the risk of the critical nonconformities and applied critical quality inspection method were showed.

Abstract

Results of research connected with determining the degree of implementation of 5S practices in ceramics industry are discussed in this paper. Direct survey with employees of companies plus expert interview was used in the research. A 21 point scale was used to assess the degree of implementation the 5S practices at individual stages of the manufacturing process. The specificity of production in ceramics industry enforces maintaining the regime of cleanliness during production. The research revealed that the level of conscious implementation of the 5S practices in companies depends on the culture of organization and the degree of involvement of employees in the improvement actions in their company. The presented results are a part of the research aimed at determining reference requirements for companies in terms of implementation and making use of the Lean Management (LM) instruments.