Elektrobudowa (Poland)

It is now possible with dissolved gas analysis and Duval Triangle 1 to distinguish between arcing faults in paper and in oil in transformers.

Platform work – which emerged recently as a separate employment technology in the post-industrial era brought to the world by the Industry 4.0 – is not regulated by employment and labour law in the majority of European countries. Legal status of people performing work at the digital work platforms is uncertain. In the period of sharing economy, it is necessary to focus on the obligation of the European Member States to comply with principles of the International Labour Organization: the everyone’s right to work in safe and healthy working conditions, to receive fair remuneration, the right of employed women to protection, the right to equal opportunities and equal treatment in matters of work and employment, the right to the protection of their claims in the event of insolvency of their employer, the right to protection in cases of termination of employment, the right to dignity at work.People employed through digital platforms work there at their own risk. They are not entitled to protection of health, social security, social and medical assistance and the right to benefi ts from social welfare services. Th e work is not a commodity, not a human service, not a technology. Instead of accepting not serious arguments that platform economy complies with all the relevant legal regulations, including lex loci laboris, the European Member States ought to at least clarify current employment status of “independent contractors,” guarantee to them the right to organize and negotiate collective agreements, payment base either on the piece or project basis, social protection, transparent system of dispute resolution between clients and workers, improve their access to information related to their clients in spe so as to develop co-operative labour management relations between representatives of workers and platform organizers. For this reasons, the phrase “(No) solidarity” – used in the title of the article – seems to make sense.

Wydawnictwo SIGMA-NOT wydaje czasopisma fachowe informujące swoich czytelników o najnowszych osiągnięciach naukowych i nowoczesnych rozwiązaniach technicznych w Polsce i na świecie, popularyzuje problemy techniczne oraz poszerza wiedzę i kulturę techniczną.

Aluminium alloys were used in many structural applications, including the civil engineering field. The innovative technology of welding with micro-jet cooling was tested and the effects were reported. The main information is given on the parameters of aluminum welding with the micro-jet cooling process. Information was also reported on the influence of various micro-jet parameters on the metallographic structure. Subsequently, metallographic and certain physical properties of welding structures (for example, mechanical resistance, electrical conductivity) were tested. Aluminum alloys are lightweight and resistant to corrosion in the natural and aquatic environment, which is why they are a suitable material for responsible structures (in the construc- tion of ships, vehicles, electrical conductors). This article focuses on the mechanical and electrical properties of busduct welds made with the micro-jet cooling pioneering technology.

<strong>New localities of species from the genus Laccobius Erichson, 1837 (Coleoptera, Hydrophilidae) in Poland</strong>. <br> The paper presents new records from Poland of nine <em>Laccobius</em> species. <em>Laccobius simulatrix</em> present occurrence in Poland is confirmed. New localites of very rare in Poland species <em>Laccobius albipes</em>, <em>L. alternus</em>, <em>L. gracilis</em> and <em>L. obscuratus</em> are given.

Dry-type transformers have been successfully used for more than 30 years in power electronics ac and dc drives and they operate correctly. Oil-filled transformers with paper insulation are also used in power electronics circuits, for instance in small power plants, in electric heating (for furnace supply). The paper insulation in these transformers degrades quickly. This is due to commutation of power electronics elements, which is accompanied by overvoltages between transformer winding and tank, with voltage change rate greater than 100V/μs.

The paper presents inuence of external factors on results of bushing dissipation factor tan and capacity measurements performed on not energized transformer as well as with operation voltage using on-line method.

This article presents the results of studies on the operational performance of the first 235 MWe with hot cyclones and 260 MWe second-generation Compact circulating fluidised bed (CFB) boiler installed as part of the repowering of the Turow power plant in Poland with close to 1,500 MWe of new capacity based on CFB technology. The main characteristic distinguishing the second generation type of boiler is the use of an integrated solids separator rather than an external cyclone. The analysis of flue gas emissions showed that the standards relating to permissible concentrations of pollutants such as SO2, NOx and CO, have been met. SO2 levels have ranged from 157 mg/mn3 to 400 mg/mmn3, levels of NOx’ from 120 mg/mmn3 to 342 mg/mmn3, and levels of CO from 7 to 45 mg/mmn3. The second-generation CFB boilers at the Turow power plant represent a major advance in CFB technology at this size. Studies on actual emissions indicated that the present standard related to permissible concentration of gas emissions and dust in flue gases have been met. The paper addresses also some performance improvements of the CFB boilers. In the boilers with external cyclones, erosion problems emerged after a time of 50 thousand hours. The problems have been quite precisely diagnosed recently and will be resolved on the occasion of the nearest shutdowns for major repairs.