Optimization of Leaf chain in Counterweight Balancing of Machine Tool by Finite Element Method

Whenever the sudden motion take place in a counterweight balancing of machine tool due to inertia effect of the heavy mass of machine tool head with counterweight exert large amount of forces in the chain link and in order to prevent failure of the chain vertical motion of the machine tool head take place at lower velocity, by increasing the efficiency of a leaf chain, we could further increases in the vertical motion of machine tool head and is still a challenges for the designer to provide not only the better stress resistance or wear resistance of a chain but also the weight saving in a chain material during its design, this could increases the chain performance as well as it could be cost efficient. The design parameters on which the efficiency of the leaf chain depend should be considered by the designer, by analyzing fatigue life and strength of a leaf chain. The CAD model of the leaf chain is developed using a Creo parametric software and finite element analysis is conducted by the help of ANSYS software, under which analysis is done by plotting sensitivities graph for the various design parameters and the factor effecting strength and fatigue life of a leaf chain, considering effect on chain link plate under a Response surface Methodology.

STRESS ANALYSIS AND TOPOLOGY OPTIMIZATION OF A CHAIN BUCKET ELEVATOR USING ANSYS

A failure of conveyor chain links in a production process can cause unscheduled shutdowns, which increase the throughput time coupled with damaged buckets and chain links, which increase maintenance and repair costs. Since failures of conveyor chains are inevitable, this research aims to modify the design of the chain bucket elevator by incorporating a ratchet mechanism, which will prevent the chain bucket assembly from dropping to the bottom of the chain bucket elevator whenever there is a chain-link failure and also avoid the jamming of the bucket chain assembly against one another when dropping to the bottom of the elevator during failure. The number of damaged buckets and chains will be minimal, thereby reducing the maintenance and repair costs. Also, the time required for replacing the failed chain link will be reduced, which in turn, will reduce the down-time, thereby increasing the production rate. The ratchet mechanism, which can withstand a maximum load of 38.10 kN, comprises a toothed wheel, a pawl, and a spring. An analytical method was employed for the initial analysis and the results were verified using the FEM. Topology Optimization was carried out on the beam and lever with results showing a 20% and 26% weight reduction from the original, respectively. The stresses induced in the beam and lever increased significantly by 36% and 47 %, respectively, because of the optimization, however, they remained within the acceptable limits.

KAJIAN PENATAAN RUANG STUDIO GAMBAR PROGRAM STUDI ARSITEKTUR DI ERA NEW NORMAL PANDEMIC COVID 19

ABSTRAK. Pada Program Studi Arsitektur salah satu proses kegiatan yang penting adalah kegiatan perancangan dengan beberapa tahapan antara lain membuat konsep, rancangan gambar dua dimensi dan tiga dimensi dan pembuatan maket. Kegiatan tersebut dilakukan di studio gambar dengan penataan dan bentuk pengelolaan desain ruang kuliah yang khusus. Pada saat sebelum pandemic desain ruang kuliah studio hanya didasarkan pada aktivitas di dalam kegiatan perancangan.Pada saat pandemic covid 19 sekarang ini mengharuskan sebuah desain ruang kuliah studio yang bisa menyesuaikan dengan kebutuhan protokol kesehatan untuk memutus rantai penyebaran virus. Metode yang digunakan adalah deduktif kualitatif dengan menggambarkan kondisi ruang kuliah studio dan penyebaran kuesioner kepada para mahasiswa melalui pengisian kuesioner online. Hasil dari penelitian ini adalah analisis desain penataan perabot ruang kuliah studio berdasarkan protokol kesehatan antara lain pada fasilitas fisik meliputi dimensi, desain wujud konfigurasi, desain pembatas antar kursi. Dimensi baru yang dihasilkan berdasarkan pertimbangan new normal adalah keefektifan sebesar 31,5% dengan jarak antar kursi minimal 1 meter. Sedangkan desain wujud konfigurasi yang paling optimal adalah tipe rectangle. Pada desain pembatas antar kursi dihasilkan desain partisi yang berfungsi menghalangi droplet antar mahasiswa dan dosen di dalam ruangan. Untuk sirkulasi dan sign diberikan tanda pada ruang kuliah studio agar arah masuk dan keluar tidak berpapasan. Dengan dihasilkannya desain ruang kuliah studio yang optimal di program studi arsitektur yang sesuai dengan kondisi pandemic covid 19 maka diharapkan akan tercapai peningkatan mutu pembelajaran juga bisa tetap mendukung program pemutusan mata rantai virus covid 19. Kata kunci:perabot, studio, arsitektur, new normal ABSTRACT. One of the essential activity processes in the Architecture Study Program is a design activity with several stages, including conceptualization, two-dimensional and three-dimensional drawing designs, and making mock-ups. This activity is carried out in a drawing studio with a particular arrangement and management of lecture room designs. Before the pandemic, the design of studio lecture rooms was only based on activities in design activities. At the time of the current Covid 19 pandemic, it requires a studio lecture room design that can adapt to health protocols' needs to break the chain of the spread of the virus. The method used is qualitative deductive by describing the studio lecture room conditions and distributing questionnaires to students through online questionnaire filling. This study analyses the design of studio lecture room furniture based on health protocols, among others, the physical facilities, including dimensions, configuration design, and barrier design between chairs. The new size produced based on the new normal considerations is the effectiveness of 31.5% with a minimum distance of 1 meter between seats.Meanwhile, the most optimal configuration design is the rectangle type. In the divider design between chairs, a partition design is produced, which functions to block droplets between students and lecturers in the room. For circulation and sign is given a warning in the studio lecture room so that the entry and exit direction does not cross. With the production of an optimal studio lecture room design in an architecture study program following the conditions of the Covid 19 pandemic, it is hoped that an increase in the quality of learning will be achieved and can continue to support the program to break the Covid 19 chain link. Keywords: furniture, studio, architecture, new normal

Factors affecting renewable energy supply chain link: A case of solar power in Vietnam

Solar power is a mature and fast-growing field based on single crystal silicon wafer technology. Although China, Europe and the US are the main markets, 80 percent of the modules are manufactured in Asia. In Vietnam, modules are manufactured in collaboration with Chinese and American manufacturers. In 2017, there were 5 GW of solar panels produced in Vietnam, accounting for 7% of the global market. The domestic solar market is expected to peak at around 1.8 GW/year according to the targets set out in the revised PDP 7. The domestic module production capacity, currently devoted entirely to export, is around 5.2 GW/year, three times the expected maximum capacity of the domestic market. In that context, due to the normal size of factories, only a few parts factories can sell to the domestic market, while the majority still must rely on exports. But it is important to map out a clear roadmap for 12 GW of solar power that will encourage the formation of EPC companies and other domestic service companies in Vietnam to build factories according to the plan. Construction, operation, maintenance, and production for the domestic market has the potential to increase Vietnam's GDP by about 0.25% by 2030 and create more than 25,000 jobs.

Mining and processing plants: Economic trends and options of corporate governance improvement

The authors closely consider the economic performance behavior of Russia’s top eight mining and processing plants over the period of a few years. Sustainability of the companies and high demand for their products in the market are highlighted. An important criterion of liquidity position of mining and processing plants (MPP is English for the Russian GOK) is the change in the net assets which have on the whole grown over the period under analysis from 38,5 to 52,8 BRub, i.e., 1.37 times. After a decline in the post-crisis period (2015–2016), the index of the net assets increased by 31 % in 2018. Inventories of all GOKs increased, and the annual average values jumped 2 times (Lebedinsky GOK–2.15 times, Mikhailovsky GOK–2.3 times, Kovdor GOK and Karelski Okatysh–2.4 time, other GOKs–1.2–1.5 times). This proves stability of the liquidity positions of the test companies. A steadily growing trend was observed in buildup of the permanent assets of GOKs: this index of the test companies was 9.6 BRub in 2011 and 22.9 BRub in 2018 (a 2.4 times growth). The highest rate growth was demonstrated by the largest GOKs: Lebedinsky (2.8 times), Stoilensky (3.4 times) and Kovdor (2.1 times). At the same time, there is a downward trend in profitability of the test GOKs, which, by the authors’ opinion, dictates the corporate governance improvement. Efficiency of the corporate governance and competitive ability of a company drastically depend on: capacity of equipment in each process stage; quality of interaction between process stages; balance of capacities of process stages; high-skilled staffing level of each link in the production chain; efficiency of management; quality of information accumulation of current data on the behavior of each production chain link.