Modifikasi Mesin Pencacah Plastik PET Tipe Gunting dengan Kapasitas 50 kg/jam

Abstrak Mesin pencacah plastik merupakan sebuah mesin yang dirancang untuk mencacah sampah plastik agar mengurangi volume sampah. Mesin pencacah dirancang mampu mencacah sampah dengan kapasitas pencacahan 50 kg/jam, hasil analisa kinerja mesin pencacah memperlihatkan bahwa kapasitas mesin pencacah adalah 36.68 kg. Analisis kinerja mesin lain adalah: efisiensi mesin nilainya 73,37 %; tingkat kebisingan mencapai 80,6 dB; getaran yang dihasilkan saat melakukan pencacahan adalah 4,9 mm/s2, dan rendemen cacahan 73,45 %. Hasil analisa kinerja memperlihatkan bawah mesin pencacah perlu dimodifikasi agar sesuai dengan hasil perancangan awal. Modifikasi dilakukan dengan mengubah saringan, mengatur ulang jarak antara mata pisau, dan menambahkan pisau pada pisau putar. Modifikasi yang dilakukan berhasil meningkatkan kapasitas mesin pencacah menjadi 42,59 kg/jam; tingkat kebisingan menjadi 76,8 dB; tingkat getaran mesin 3,84 mm/s2; dan kualitas hasil cacahan menjadi baik yaitu plastik terpotong. Kata kunci: modifikasi, kinerja, sampah, daur ulang, mata pisau Abstract The plastic chopping machine is a machine designed to chop plastic waste in order to reduce the volume of waste. The chopping machine is designed to be able to chop waste with a chopping capacity of 50 kg / hour, the results of the chopping machine performance analysis show that the chopping machine capacity is 36.68 kg. Other engine performance analyzes are: the engine efficiency is 73.37%; noise level reaches 80.6 dB; The vibration generated during the counting was 4.9 mm / s2, and the chopping yield was 73.45%. The results of the performance analysis show that the chopping machine needs to be modified to match the results of the initial design. Modifications were made by changing the filter, resetting the distance between the blades, and adding blades to the rotary knife. The modifications made were successful in increasing the capacity of the chopping machine to 42.59 kg / hour; noise level to 76.8 dB; machine vibration level 3.84 mm / s2; and the quality of the chopped results is good, namely the plastic is cut. Key words: modification, performance, waste, recycling, blade

Sequential Periodic Motions in a Vibration-Assisted, Regenerative, Nonlinear Turning-Tool System

This paper studies the dynamics and bifurcations of a vibration-assisted, regenerative, nonlinear turning-tool system using an implicit mapping method. Machine vibration has been studied for a century for the improvement of machine accuracy and metal removal rate. In fact, this problem is unsolved yet. This is because such dynamical systems are involved in nonlinearity, discontinuity and time-delay. Thus, a comprehensive understanding of nonlinear machining dynamics with time-delay is indispensable. In this paper, period-[Formula: see text] motions in the turning machine-tool system are studied through specific mapping structures, and the corresponding stability and bifurcations of the period-[Formula: see text] motion are determined through the eigenvalue analysis. The analytical bifurcation scenarios for two sets of sequential period-[Formula: see text] motions in a turning-tool system are presented. Numerical simulations of period-[Formula: see text] motions are carried out to verify the prediction of periodic motions. The complex dynamics of vibration-assisted machining with strong nonlinearity are presented, which can provide a good overview for nonlinear dynamics of machine-tool systems.

On underwater sound radiation in a towing tank induced by continuous machine vibration in a steel circular cylinder

An understanding of the characteristics and mechanisms of structural vibrations produced by underwater vehicles is required to reduce sound radiation in submarine environments. In this study, experiments were performed using a continuously running machine to produce low-frequency vibrations in a submerged, watertight, steel circular cylinder in the centre of a 176 × 8 × 4 m3 towing tank, and the underwater radiation sound field was measured. Finite element method simulations of the system were also performed and showed good agreement with the experimental results. The wall effects of the towing tank were simulated in detail by changing the alternative impedances of the wall. The reflection and acoustic impedance of the towing tank walls were found to significantly affect the underwater sound field in both the experiments and simulations. An analytical solution was used to verify the frequency range applied in the simulation analysis. The results of this study provide a measurement procedure and a simulation method, which can be used to evaluate the underwater radiation sound field from the vehicle machine running in the water at wall boundary environment.

Blind Application of Developed Smart Vibration-Based Machine Learning (SVML) Model for Machine Faults Diagnosis to Different Machine Conditions

Purpose The development and application of intelligent models to perform vibration-based condition monitoring in industry seems to be receiving attention in recent years. A number of such research studies using the artificial intelligence, machine learning, pattern recognition, etc., are available in the literature on this topic. These studies essentially used the machine vibration responses with known machine faults to develop smart fault diagnosis models. These models are yet to be tested for all kinds of machine faults and/or different operating conditions. Therefore, the purpose is to develop a generic machine faults diagnosis model that can be applied blindly to any identical machines with high confidence level in accuracy of the predictions. Methods In this paper, a supervised smart fault diagnosis model is developed. This model is developed using the available measured vibration responses for the different rotor faults simulated on an experimental rotating rig operating at a constant speed. The developed smart vibration-based machine learning (SVML) model is then blindly tested to identify the healthy and faulty conditions of the rig when operating at different speeds. Results and conclusions Several scenarios are proposed and examined during the development of the SVML model. It is observed that scenario of the vibration measurements simultaneously from all bearings from a machine is capable to fully map the machine dynamics in the VML model. Therefore, this developed when applied blindly to the sets of data at a different machine speed, the results are observed to be encouraging. The results clearly show a possibility for a centralised vibration-based condition monitoring (CVCM) model for identical machines operating at different rotating speeds.