Compression Rubber Damper Assessment Through Simulation

Rubber torsional vibration dampers are often used on mid-range engines. Usually, the geometry of a rubber torsional vibration damper is such that the rubber element in it undergoes shear. However, in the work presented, a compression rubber damper is being proposed, in which the rubber element undergoes compression rather than shear. The proposed compression rubber damper, just like the shear rubber damper, is a tuned damper. An analytical tool is being used to evaluate the stiffness of compression rubber design and thus evaluate its performance. The rubber geometry, material and plate design are selected through simulations. The analytical tool demonstrates the functionality of the compression rubber damper paper and focuses on simulation-based product development using ANSYS for FEA and an in-house tool for torsional vibration analysis.

The effect analysis of the stiffness changes of a Traditional Fishing Boat Foundation on Vibration Amplitude

The ship with the outboard engine is intended to make it easier for fishers to operate and maintain. However, the magnitude of the vibration due to the excitation of the engine during operation adversely affects the surrounding structures. It is evidenced by measuring the vibration amplitude of more than 0.02 mm at several points around the ship engine foundation. This study aims to reduce these vibrations by changing the canal's dimensions as a foundation and using damping rubber as the simplest solution. The analysis was carried out by calculating the vibration parameters of 2 types of machines, SR1110 and S1100. The numerical method is used to calculate the vibration's amplitude by varying the value of channel stiffness and rubber damping on the machine foundation. Supporting data is obtained by measuring the vibration amplitude at several points around the foundation. The magnitude of the previous vibration amplitude is 0.078 mm for the SR1110 type and 0.069 mm for the S1100 type, which exceeds the limit still. The amplitude is reduced by changing the foundation's dimensions and using a rubber damper (c). With the new foundation dimensions, the amplitude for the diesel engine type SR1110 becomes 0.0245 mm and type S1100 becomes 0.0238 mm. Increased stiffness and the addition of rubber succeeded in reducing the vibration amplitude by a significant value. The amplitude was reduced by 69% for the SR1110 engine type and 65% for the S1100 engine type within the allowable limit of less than 0.02 mm to 0.03 mm based on Barkan's observation results.

RANCANG BANGUN RUBBER DAMPER PADA LORI INSPEKSI ELEKTRIK

Sistem suspensi merupakan komponen penting dalam kendaraan, karena berfungsi sebagai peredam getaran bagi kendaraan ketika dikendarai oleh penggunanya. Ada beberapa jenis sistem suspensi yang diterapkan pada kendaraan. Salah satu komponen yang paling penting dalam meredam getaran adalah karet. Pembuatan suspensi karet dimulai dari perencanaan. Perencanaan ini meliputi proses desain dan pemilihan material. Desain karet menggunakan software autodesc inventor dengan memperhatikan kekuatan karet. Desain lebih menitik beratkan pada kekuatan karet ketika menerima beban. Lori inspeksi dirancang dengan kecepatan operasional 20 Km/jam dan kecepatan maksimum 25 Km/jam. Pemilihan bahan dengan menggunakan beberapa campuran bahan kimia dan karet alam yang dominan untuk menambah kekuatan karet. Pembuatan karet dilakukan di tempat industri karet CV Juwahir Berdikari yang berada di Gorang gareng kabupaten Magetan. Dengan beberapa tahapan proses yang membutuhkan mesin khusus untuk menghasilkan produk dari karet. Proses produksi tersebut dimulai dari pencampuran komposisi bahan karet, penyiapan cetakan karet, dan pengepresan kemudian finishing. Hasil dari pembuatan karet akan dipasang di chasis lori inspeksi.

PROTOTIPE LORI INSPEKSI ELEKTRIK BERTENAGA SURYA (LORI PPI E-2000 GENERASI 3)

Penggunaan lori inspeksi dalam kegiatan perawatan prasarana sangat dibutuhkan untuk meminimalisir tenaga dalam pemeliharaan dan efisiensi waktu. Pengembangan lori inspeksi di Politeknik Perkeretaapian Indonesia Madiun terus dilakukan mulai dari motor penggerak, roda, frame, bodi, rubber dumper dan panel surya sebagai sumber energi utama. Motor penggerak menggunakan motor listrik BLDC (Brushless direct current) dengan daya 2680 Watt, arus 35 A dan kecepatan putar 4250 Rpm yang ramah lingkungan. Pengembangan roda lori inspeksi menggunakan struktur monoblok dengan proses pengecoran. Material yang digunakan berasal dari besi cor nodular (FCD), memiliki tingkat kekerasan rata-rata 191 HB. Rubber damper dikenal sebagai peredam kejut dengan panjang 185 mm, lebar 60 mm, dan tinggi 30 mm. Komposisi bahan Rubber damper sebagai berikut: Karet alam 55%, Carbon black 25%, White oil 5%, Zine oxide 3%, Accelerator 2%, Anti Oxidant 2%, Steread Axid 3%, dan Sulfur 5%. Bodi lori inspeksi terbuat dari material komposit jenis fibre reinforced polymers of plastics (FRP). Komposit ini menggunakan polimer berbahan resin polyester sebagai matriks (pengikat) dan penguatan serat gelas jenis fibrous dengan metode hand lay-up. Solar panel sebagai sumber energi utama untuk mensuplai daya arus listrik motor listrik penggerak. Solar panel dapat bekerja dengan optimal dengan presentasi Pmax mencapai 99,29% dan kemampuan jarak tempuh sejauh 11 Km. Alat pengukur geometri jalan rel dilengkapi dengan sensor maxbotik sebagai pendeteksi lebar jalan rel, gyroscope sebagai pendeteksi beda tinggi dan KTR displacement sensor sebagai pendeteksi keausan rel. Desain lori inspeksi elektrik PPI Madiun memiliki nilai estetika maupun ergonomi yang tinggi.

Seismic Optimization of Concrete Gravity Dams Using a Rubber Damper

One of the major factors in an economic project of new concrete dams and safety valuation of available dams in seismic areas is the control and dissipation of the induced hydrodynamic pressure induced by dam and reservoir interaction. As one of the main control functions, dissipating the induced hydrodynamic pressure on the upstream face of the dam is considered in the evaluations. In this paper, the effects of a rubber damper as an isolation layer on the dam's seismic control have been investigated. For optimization of the rubber damper thickness and height, the Monte Carlo probabilistic analysis is used. The ANSYS program on the basis of finite element technique is applied for modeling and analysis. The Pine Flat dam in California, due to components of El Centro, San Fernando and North Ridge earthquake is modeled as a case study to evaluate the effect of upstream isolation layer on seismic control and optimization. The effect of the thickness and height of the rubber damper on reducing the responses is investigated and the optimum thickness and height are selected using sensitivity analysis for safe and economic design. The obtained results show the capability of the rubber damper in the seismic and hydrodynamic control of the sample model.

Effect Of Rubber Damper Stiffness And Tire Pressure To Reduce Ground Reaction Load Factor On Main Landing Gear Using Multi-Body Simulation (MBS) Rigid Model

Landing Gear Drop Test (LGDT) utilizes the apparatus requiring a substantial time and cost. Virtual LGDT (vLGDT) using MSC ADAMS software is one of the solutions for initial stage to testing landing gear. From simulation with vsink 1.7 m/s and load 22000 N obtained contact/impact force that ensue in MSC ADAMS was 73650 N, while from experimental was 73612 N. The difference between vLGDT and LGDT result is 0.05 %. To obtain ground reaction load factor below 3 in vsink = 3.05 m/s, the rubber damper should have stiffness in the range of 1900 - 2100 N/mm and for the tire pressure of 60 - 65 psi.