Lean Manufacturing Process Planning for 5 Axes CNC Driven Milling Machine

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LEAN MANUFACTURING PROCESS PLANNING FOR 5 AXES CNC DRIVEN MILLING MACHINE

The aim of this publication is to determine the OEE (Overall Equipment Efficiency) indicator for 5 axes milling machine found at Diehl Aircabin Hungary Ltd. for the present and future state. Based on this value, the utilization of the machine for the given production amount can be calculated. With the optimal choice of the right production parameters (the number of cuts, feeding, depth of cut, etc.) greater productivity can be achieved i.e. the machine main time (time of cutting) will be less. The possibilities of the reduction of the machine time will be analysed and calculated. Setting of the appropriate technological parameters the machine main time could be decreased. The calculation of the machine main time will be determined for the most frequent manufacturing technologies

Számelmélet a középiskolában

Számelmélet a középiskolábanB

Application of (V)UV/O3 technology for post-treatment of biologically treated wastewater: A pilot-scale study

For the first time, high energy VUV photons and generation of O3 by (V)UV lamps were applied together for removal of active pharmaceutical ingredients (APIs) from biologically treated wastewater (BTWW) in pilot-scale. The core of the pilot container unit was a photoreactor assembly consisting of six photoreactors, each containing a low-pressure Hg lamp (UV dose of 1.2 J/cm2 and 6.6 J/cm2 at 185 nm and 254 nm, respectively). BTWW was irradiated (4.75 min residence time) by (V)UV light in presence of in situ photochemically generated O3 from coolant air of the lamps. Experiments were conducted at the site of two wastewater treatment plants. Out of seven target APIs (namely carbamazepine, ciprofloxacin, clarithromycin, diclofenac, metoprolol, sitagliptin, and sulfamethoxazole), 80–100% removal was accomplished for five and 40–80% for two compounds. Two degradation products of carbamazepine were detected. Degradation products of other target compounds were not found. The applied O3 dose was 30–45 μg O3/mg dissolved organic carbon. Inactivation of up to log-4.8, log-4.5 and log-3.8 could be achieved for total coliform, Escherichia coli and Enterococcus faecalis, respectively. SOS Chromotest indicated no genotoxicity nor acute toxicity. Generation of neither NH4+, NO2− nor NO3− was observed during post-treatment. Electric energy per order values were calculated for the first time for (V)UV/O3 treatment in BTWW with a median value of 1.5 kWh/m3. This technology can be proposed for post-treatment of BTWWs of small settlements or livestock farms to degrade micropollutants before water discharge or for production of irrigation water. Further studies are essential in pilot-scale for other applications

Laponite immobilized TiO2 catalysts for photocatalytic degradation of phenols

Laponite immobilized titania catalysts were prepared by a pillaring process and by hydrothermal synthesis (HT) applying different titania sources such as TiCl4 and TiOSO4. Textural investigations (XRD, TEM, N2 physisorption) evidenced that by the pillaring procedure a high specific surface area (~450 m2/g) mesoporous composite with 5-6 nm sized anatase nanoparticles were formed retaining the morphology of parent laponite structure. In contrast, by hydrothermal treatment with titanium oxysulfate the initial laponite structure was destroyed and a more opened nanoporous silica/titania material was formed with bigger, about 14 nm anatase particles. FT-IR spectroscopic investigations revealed the different acidic character of titania/laponite composite samples showing stronger Lewis and weak Brönsted acid sites on both catalysts. However, acidic centers in titania pillared laponite stem from Ti–O–Si bonds, whereas in HT sample from the separated, ionic, surface sulfate species on titania. Catalytic activity of titania/laponite composites were tested in photo-oxidation of model 10–5 M phenol and 2,4,6-trichlorophenol (TCP) water solutions. Catalytic tests were carried out in a home constructed batch-type photo-reactor with oxygen bubbling, and applying commercial low pressure Hg lamps emitting UV-light at 254 nm and 361 nm. Catalytic results showed that utilization of titania/laponite catalysts enhanced the photo-oxidation activity. Hydrothermally prepared sample showed much better catalytic performance than titanium chloride pillared one, probably due to the bigger titania particles and the more opened mesoporous structure of titania/laponite HT, and moreover to the peculiar surface acidic properties of sulfated titania species. Separation of catalysts from reaction media even in tap water was much easier than that of commercial titania, i.e. by self-settling