Implementasi SMED: Perbaikan Waktu Changeover Part pada Line Produksi Seat di PT. Selamat Sempurna, Tbk

PT. Selamat Sempurna, Tbk is a company that manufactures automotive parts, namely car filters. This filter product has many part numbers. In this company has one of the production lines, namely Line Seat Press Shop, this line produces components from filters, namely seat components. Seat is the main part of the filter component that functions as a filter holder to the engine. This Seat component consists of several part numbers (shapes or variations) following the filter product, and some part numbers handled by the manual engine B070 & L224 will affect the changes in the production engine settings. This production machine includes machines that require time in a slow setup process for switching dies when switching from one part number to another part number compared to other machines, because the element of the process setting is long. With a fishbone diagram, the root cause of the Change Over Part long problem on the machine is from the method category (there is no preparation desk dies and there is not separation of external setup and internal setup). Previously the time needed for Change Over Part was 1961 seconds. After knowing the root cause of the problem and the improvement of the time needed is only 866 seconds. The time difference is 1067 seconds, so save on average time 1095 seconds or 18 minutes / setup. Keywords: Filter product, Change Over part (COP), Fishbone Diagram, Setup, Process Elements.

Size Dependent Particle Removal Efficiency and Pressure Drop of a Dust Cleaning Material For Use as Facemask Filters for Protection during COVID-19

The COVID-19 pandemic has caused a severe demand for facemasks, and this has resulted in the use of those made from alternate media. As SARS-CoV-2 spreads primarily due to airborne droplets, it is critical to verify the filtration efficiency of these alternate media based facemasks. While several media are being tested and used, commercially available dust cleaners have shown reasonable filtration efficiency. This may also be due to the potential electrostatic charge on the surface which enhances capture of the fine particles. In this manuscript, we report the size dependent filtration efficiency studied systematically in a filter holder-based system as 47 mm punches; and test results on a mannequin that was 3D printed wearing a bandana mask that was placed in a chamber.

New insights into silt density index and modified fouling index measurements

In order to investigate the accuracy and reproducibility of the parameters SDI (silt density index) and MFI (modified fouling index), tests in diverse conditions were performed: with three different types of filter holder, two microfilter pore sizes, with and without permeate spacer and with two foulants (alginate as organic foulant and silica flour as the particulate). Additionally the effect of pressure on fouling indices was analysed. It was concluded, that there is a need to define more boundary conditions in the ASTM standard (exact type of filter holder, exact type of membrane, start conditions) for the SDI to achieve a parameter with reliable and comparable values. But in comparison to MFI, SDI seems to be a more robust parameter for a use in practice pertaining to the influence of a feed pressure level and the effective membrane area. The MFI gives more insights in acting mechanisms and offers advantages for research. It shows a correlation to a concentration of particulate or organic foulants. Like the SDI, it is necessary to define and standardize exact boundary conditions for the MFI tests (classified by the use of MF, UF or NF filter media).