Sustainable Solution to Low-Cost Alternative Abrasive From Electric Ceramic Insulator Waste For Use in Abrasive Water Jet Machining

Increasing demand and resource overuse has prompted the exploration of spent secondary materials as a primary raw material for a variety of applications, leading to a more sustainable environment. Spent electric grid ceramic insulator, one of the waste materials of ceramic industry has a good hardness and strength. It can be reused as value added material in Abrasive Water Jet Machining (AWJM) industry. This present work deals with conversion of electric insulator rejects (EIR) into a cost-effective replacement material for abrasive water jet machining process. Mechanical crushing method is opted to generate the abrasive grit for the machining process. Grit generation pattern and the friability of the electric insulator rejects were determined experimentally. The results indicate that the friability of the processed electric insulator rejects is comparable with the commercially available garnet abrasive. Geometric parameters such as sphericity, elongation ratio, and shape factor for the processed electric insulator rejects were studied using scanning electron microscopy. The machining performance indicators for standard aluminium material such as volume of material removal, kerf angle, surface roughness and cutting width were measured for electric insulator rejects and compared with existing garnet abrasive grain. The experimental results of newly generated electric insulator reject abrasive were matched with performance indicators of the garnet abrasive. The observed deviation was lower proving that it can be used as alternative abrasive in the abrasive jet machining process. Cost analysis and recycling ability predict the economical usability of the newly generated abrasives.

Effects of Flash Sintering Parameters on Performance of Ceramic Insulator

Ceramic outdoor insulators play an important role in electrical insulation and mechanical support because of good chemical and thermal stability, which have been widely used in power systems. However, the brittleness and surface discharge of ceramic material greatly limit the application of ceramic insulators. From the perspective of sintering technology, flash sintering technology is used to improve the performance of ceramic insulators. In this paper, the simulation model of producing the ceramic insulator by the flash sintering technology was set up. Material Studio was used to study the influence of electric field intensity and temperature on the alumina unit cell. COMSOL was used to study the influence of electric field intensity and current density on sintering speed, density and grain size. Obtained results showed that under high temperature and high voltage, the volume of the unit cell becomes smaller and the atoms are arranged more closely. The increase of current density can result in higher ceramic density and larger grain size. With the electric field intensity increasing, incubation time shows a decreasing tendency and energy consumption is reduced. Ceramic insulators with a higher uniform structure and a smaller grain size can show better dielectric performance and higher flashover voltage.

Pollution Severity Diagnose on Solid Insulators using the Partial Discharge and Flashover Characteristics

In this paper deals with the investigation of partial discharge and flashover characteristics of the ceramic and non-ceramic insulators in order to succeed a best diagnostic tool to determine the pollution severity of exterior insulators. In this experiment, laboratory based tests are achieve on the ceramic and non-ceramic insulators under AC voltage at various pollution levels manipulate the sodium chloride (NaCl) a as contaminant. Initially the test are conducted by the pure and contaminated at sample of insulators. In supplement, Partial discharge (PD) occurs on the contaminated surface of the sample insulator is to be measured and to investigate the PD wave form. The PD detection is sufficient to analyze maintenance of insulators of the transmission line. To evaluate the statistical analysis of PD patterns in order to accomplish a numerical judgment of pollution severity of the ceramic and non-ceramic insulators. In consequence, ceramic and non-ceramic insulator exhibit the pollution severity of the exterior insulators should be recognized from the partial discharge patterns investigation.

Studi Pola Arus Bocor Isolator Keramik Selama Waktu Pemakaian 24 Jam

ABSTRAK Isolator merupakan komponen yang penting dijaga keandalannya dalam sistem transmisi dan distribusi tenaga listrik. Isolator rentan mengalami kegagalan akibat lingkungan, karena terpapar langsung kondisi dimana isolator tersebut terpasang. Salah satu jenis isolator yang sering digunakan adalah bahan keramik, dimana memiliki kelebihan diantaranya kekuatan mekanik yang cukup handal. Namun kekurangan isolator jenis ini adalah sifat permukaannya yang hidrofilik, yaitu mudah menyerap air sehingga bila digunakan pada kelembaban tinggi cenderung memicu timbulnya arus bocor. Arus bocor merupakan parameter penting pada isolator karena sering menjadi penyebab kegagalan isolator. Untuk mengetahui seberapa besar pengaruh kondisi lingkungan terhadap arus bocor, dilakukan pengujian terhadap isolator keramik dalam waktu 24 jam. Data arus bocor diambil setiap 3 jam untuk melihat perubahannya berdasarkan perubahan kelembaban, dan suhu lingkungan. Hasilnya didapat bahwa semakin tinggi kelembaban udara, dan semakin rendah suhu lingkungan maka arus bocor semakin tinggi. Hasil penelitian ini dapat dijadikan acuan untuk mengantisipasi kegagalan isolator keramik akibat arus bocor sehingga keandalan sistem tenaga listrik dapat terjaga. Kata kunci: Isolator keramik, Lingkungan, Kelembaban, Suhu. ABSTRACT Isolator is an important component that must be maintained to keep electric power transmission and distribution system reliability. Isolators are susceptible to failure due to the environment, because they are directly exposed to conditions where the insulator installed. Ceramic insulator is one type of isolator that is often used, which has advantages including mechanical strength that is quite reliable. However, the lack of this type of isolator is its hydrophilic surface, which is easy to absorb water so that when used at high humidity tends to trigger a leakage current. Leakage current is an important parameter in an insulator because it can be a cause due to insulator failure. To find out how environmental conditions impact on leakage currents along day, a ceramic isolator is tested within 24 hours. Leakage current data is taken every 3 hours to see the changes based on changes in humidity, and ambient temperature. The result is the higher humidity of the air, and the lower ambient temperature, can make insulator leakage current rise up. The results of this study can be used as a reference to anticipate the failure of ceramic insulators due to leakage currents so that the reliability of the electric power system can be maintained. Keywords: ceramic insulator, environtment, humidity, temperature.

Effect of Ceramic Aggregate and Fly ash in Normal Strength Concrete

In this study, full and partial replacement of stone aggregate by ceramic insulator scrap and partial replacement of cement by fly ash has been done in order to enhance economy in construction. More once, the solution of disposal of wasting from ceramic insulator manufacturing company and thermal power plant is also achieved. Further various mechanical properties of ceramic insulator scrap such as crushing value, impact value, abrasion value, specific gravity, sieve analysis and water absorption has been studied and obtained to make the study fruitful. Concrete of grade M15 is used to study the compressive strength properties of stone and ceramic aggregates. Replacement of stone aggregates by ceramic aggregates has been done in stages starting from 0% to 100% each stage possessing the variation of 10% and in all the specimens 30% of cement is replaced by 35% of fly ash. Six number of cube samples are cast for each variation and the compressive strength of the same have been obtained at 7, 28 and 56 days of age. Totally 216 cubes are cast and tested for compression. It is found that the optimum percentage at which the stone aggregate can be replaced by ceramic aggregates is 50% and 30% of cement can be replaced by 35% fly ash.