Perancangan Mesin Vakum dan Pengemasan Untuk Produksi Olahan Jamur Tiram Dalam Rangka Meningkatkan Nilai Jual dan Masa Pakai

The design of this Vacuum and Packaging Machine is made in order to increase the sale value and service life for processed Oyster Mushroom products. Not only that, this machine can do packaging in a short time and efficiently. This machine consists of Frame, Vacuum Motor, Impulse Sealer, Vacuum Clamp. This Vacuum and Packaging Machine has dimensions of length 700 mm x width 500 mm x height 700 mm. The impulse sealer used is Arashi Ais 400 type by using a VE115N 2 CFM type vacuum motor. From this vacuum motor will later be connected to the vacuum clamp as a tool to clamp the packaging during the process of vacuuming the air in the package. This machine is equipped with a limit switch on the vacuum clamp that works to connect the current to the vacuum motor so that the vacuum motor automatically turns on. The operation of this vacuum and packaging machine is quite simple by inserting the packaging containing the product into the sealer and at the end of the package clamped on the vacuum clamp, the vacuum motor will automatically turn on, the next step is to operate the impulse sealer so that the product is finished packed under vacuum. From the design results, the bending stress of the frame is 3.172 N / mm2, the working time of the vacuum and sealer is 1.54 s per package, and the estimated price of the machine is Rp. 1,879,000

Transparent Flexible IGZO Thin Film Transistors Fabricated at Room Temperature

Flexible and fully transparent thin film transistors (TFT) were fabricated via room temperature processes. The fabricated TFT on the PEN exhibited excellent performance, including a saturation mobility (μsat) of 7.9 cm2/V·s, an Ion/Ioff ratio of 4.58 × 106, a subthreshold swing (SS) of 0.248 V/dec, a transparency of 87.8% at 550 nm, as well as relatively good stability under negative bias stress (NBS) and bending stress, which shows great potential in smart, portable flexible display, and wearable device applications.

Precise mathematical model for the ratchet tooth root bending stress

A ratchet is an essential component of the ratchet pawl mechanism. But the traditional ratchet strength check method has certain limitations in the design process. In this paper, the stress analysis of the ratchet is discussed and a precision mathematical model for the ratchet tooth root bending stress is proposed for the first time. This model was established by the folded section and defined by the incision effect theory. To test the prediction ability of the proposed mathematical model, the maximum stress of three standard ratchets and one non-standard ratchet were analyzed by the FEA (finite element analysis) method. The non-standard ratchet was adapted in the ratchet experiment to analyze its maximum stress. The analysis results presented in this paper show that the proposed mathematical model has a good predictability, regardless of whether it is a standard or non-standard ratchet. It is recommended that this model can be used to predict the ratchet tooth root bending stress in the ratchet design process.

Comparison between Tests and Simulations Regarding Bending Resistance of 3D Printed PLA Structures

Additive manufacturing is one of the technologies that is beginning to be used in new fields of parts production, but it is also a technology that is constantly evolving, due to the advances made by researchers and printing equipment. The paper presents how, by using the simulation process, the geometry of the 3D printed structures from PLA and PLA-Glass was optimized at the bending stress. The optimization aimed to reduce the consumption of filament (material) simultaneously with an increase in the bending resistance. In addition, this paper demonstrates that the simulation process can only be applied with good results to 3D printed structures when their mechanical properties are known. The inconsistency of printing process parameters makes the 3D printed structures not homogeneous and, consequently, the occurrence of errors between the test results and those of simulations become natural and acceptable. The mechanical properties depend on the values of the printing process parameters and the printing equipment because, in the case of 3D printing, it is necessary for each combination of parameters to determine their mechanical properties through specific tests.

ANALISA HASIL UJI KEKUATAN TARIK, TEKAN & STRUKTUR MAKRO SAMPAH PLASTIK JENIS PET, HDPE, DAN CAMPURAN (PET+HDPE)

Plastik is a material which has difficult to decompose. Therefore, the utilization of waste into useful material is important to do. This study aims to identify the tensile strength, bending, and macro structure of recycled PET, HDPE, and PET + HDPE plastik waste mixtures and recommendations for plastik products that fit the characteristics of these plastik types. PET and HDPE plastik waste is melted with oil and reprinted into tensile and bending test samples in accordance with predetermined variations, and then the results of the fracture are analyzed in a macro structure. Based on tensile testing, the tensile strength test results have the highest stress and strain values obtained in the mixture of 40% + HDPE 60% (B2) used oil specimens of 10.58 MPa and strain values of 11.98%. The results of bending strength testing which has the highest bending stress value and maximum load value are obtained in plastik mixture specimens with 30% used oil mixture + 70% HDPE (B1) of 11.58 MPa and for maximum load values of 43.33 KN. Testing the tensile strength and bending strength of the type of plastik mixture Oil and HDPE + PET (50%: 50%), the results obtained can still not be recommended to be used as a paving block product because the value of stress, strain, bending stress, and the maximum load is still relatively low, namely for the tensile test the highest variation of stress value is 5.21 MPa, the highest variation of strain value is 5.23%, the maximum load value is 10 KN, and the highest variation of bending stress value is 40% + 60% by 4.01 MPa.

Stiff String Casing Design: Tortuosity and Centralisation

The forces and stresses along casing strings are modeled using a stiff string torque and drag model. The effect of wellbore tortuosity and centralization are quantified in preplanning phase in addition to the effect of 3D orientated casing wear. A realistic case study is presented to show the resulting effect on axial, burst, collapse and Von Mises equivalent (VME) safety factor as well as VME body and connection design envelopes. While running a tubular downhole, a smooth wellbore is normally assumed when performing a torque and drag calculation. In reality, the inherent tortuosity of the wellbore which is caused by the drilling process can cause significant local doglegs. When applying a soft-string torque and drag model, the stiffness, radial clearance and high frequency surveys needed to fully model local doglegs are rarely modeled. The stiff string torque and drag and buckling model can model these effects, as well as the addition of rigid and flexible centralisers. This study involves the comparison of different casing design load cases, under different centralizer programs and tortuosity taking into account a 3D orientated casing wear. The results show that there can be significant differences in overall axial stress depending on the centraliser program and tortuosity used. The soft string model doesn't directly account for bending stress, normally this is estimated using a Bending Stress Magnification Factor (BSMF). In contract the stiff string model can directly calculate the additional bending stress. This additional stress can be particularly prevalent while RIH casing with centralisers and high tortuosity. The reduction in American Petroleum Institute (API) and VME stress envelope is also quantified using a 3D orientated casing wear model. A better understanding of axial stress state reduces risk of well integrity issues. This paper will show the benefits of using a stiff string model, considering additional contact points, bending stress as well as the benefits of modelling tortuosity and centralizer program early in the design process. During extended reach drilling (ERD) and high-pressure, high temperature (HPHT) wells, this information can be critical when correctly assessing the axial stress state.

Analysis of the behaviour of 3D samples printed by FFF/FDM technologies under bending stress with a focus on infill

The focus of this paper is to explore the possibilities of optimizing 3D printed elements produced by FFF/FDM technology based on bending tests according to ČSN EN ISO 178 (64 0607) with variations in the settings of the printing itself. The principle of FFF/FDM is the printing of a continuous fiber made of thermoplastic material, which is applied by machine to the previously printed fiber. There are many combinations of possible print settings, and one of them is the geometry of the inner density with variable density. Their resulting maximum values of the achieved load were then compared with the weight (amount of material used) and printing time. The result is a comparison to achieve economical printing with the greatest possible load capacity.

Experimental Study on Single Corner Cold Bending Mechanical Response of Laminated of PVB Interlayer Tempered Glass Panes and the Coupling Effect with Load

The cold bending method is a type of curved glass curtain wall construction method that has been used in practical engineering for a short time. It has the advantages of simple operation, high efficiency and low cost. However, the mechanical response and properties of glass panes caused by cold bending have not been solved effectively. To study the mechanical response and the properties of cold formed laminated tempered glass panes after applying with a wind load, cold bending and load tests of 9 laminated tempered glass panes were conducted by the orthogonal experimental design method. The effects of cold bending curvature, glass pane thickness and interlayer thickness were considered. In this paper, the response law of cold bending stress to the curvature and the relationship among the influencing factors were analyzed. The variation process of stress, the deflection of cold-formed glass panes under uniform load and the characteristics affected by cold-formed stress and deformation were studied. The results show that the cold bending stress is distributed in a saddle shape, and the curvature has the greatest influence on the cold bending stress, followed by the thickness of the glass panes. The influence of the interlayer thickness is small. The maximum stress appears near the corner of the short side direction adjacent to the cold bending corner. The cold bending stress increases linearly with increasing cold bending curvature. The cold bending stress and deformation have little effect on the change process of the later stage load effect.

VIV Fracture Investigation into 3D Marine Riser with a Circumferential Outside Surface Crack

Vortex-induced vibration (VIV) is one of the most common dynamic mechanisms that cause damage to marine risers. Hamilton’s variational principle is used to establish a vortex-induced vibration (VIV) model of a flexible riser in which the wake oscillator model is used to simulate cross-flow (CF) and inline flow (IL) vortex-induced forces and their coupling, taking into account the effect of the top tension and internal flow in the riser. The VIV model is solved by combining the Newmark-β and Runge–Kutta methods and verified with experimental data from the literature. Combining Option 1 and Option 2 failure assessment diagrams (FADs) in the BS7910 standard, a fracture failure assessment model for a marine riser with circumferential semielliptical outside surface cracks is established. Using the VIV model and FAD failure assessment chart, the effects of riser length, inside/outside flows, and top tension on the VIV response and safety assessment of marine risers with outside surface cracks are investigated. It is shown that increasing the top tension can inhibit the lateral displacement amplitude and bending stress in a riser, but excessive top tension can increase the axial stress in the riser, which counteracts the decrease in the bending stress, so that the effect of top tension on crack safety is not significant. The increasing outside flow velocity significantly increases the lateral vibration amplitude and bending stress in the riser and reduces the crack safety. When other parameters remain unchanged, increasing riser length has no significant effect on the vibration amplitude of the lower part of the riser.