Pengaruh Waktu Penahanan pada Perlakuan Panas Paska Pengelasan terhadap Ketangguhan Sambungan Las Baja

One of the welding methods that is widely used today because it is easier to operate, more practical in its use, can be used for all welding positions and more efficient is called Shield Metal Arc Welding (SMAW). In this welding, the base metal and filler metal will experience thermal cycles which lead to local heating and cooling processes resulting in residual stress and distortion in the material. This residual stress must be removed because it causes a decrease in the mechanical properties of the material. The most widely used method is the thermal method that is by Post Weld Heat Treatment (PWHT). The success of The post-weld heat treatment in removing residual stresses in PWHT is influenced by the holding time. This study aims to examine the effect of holding time on heat treatment, on the weld toughness of steel. In this study, the type of welding used was SMAW welding, the material used was steel AISI 4130, the electrodes used were LB-7018-1 standard application and AWS classification A5.1 E7018-1. The test holding temperature is 650oC. The holding time of testing uses three variables, namely: 2.5 hours, 4.5 hours, 6.5 hours. The Impact testing is done by the Charpy method. From this study, the influence of holding time variation on PWHT holding temperature on the weld strength of AISI 4130 steel was obtained.

Aplikasi 3D Printer Fused Deposite Material (FDM) pada Pembuatan Pola Cor

Metal Casting Industry has a classic problem in handling the production process and quality assurance. This research aims to provide solutions to solve the problems of the metal casting industry by introducing and applying 3D printers with a fused deposit material system. this technology is used to streamline the production process of cast patterns. The process of making a casting pattern usually takes 70% of the total production time of a cast product. The purpose of this study is to examine the application of making cast patterns with a 3D printer with a fused deposit material system. The research methods carried out are (1) create of 3D CAD cast patterns, (2) conversion to STL format, (3) 3D printer setup, (4) printing process, (5) analysis, (6) conclusions. The results obtained are a 3D printer with a fused deposit material system that can be used to make cast patterns. From the analysis of the accuracy of the cast pattern with the 3D printer has a difference in size ranging from 0.2 mm. As for the analysis of the quality of the geometry, the results of the cast pattern of the 3D printer with the fused deposit material system have a good shape but lack results on the surface. Thus a 3D printer with a fused deposit material system is suitable for making cast patterns because it has a consistent tendency and ease in making cast patterns. This opens up opportunities for continued development of 3D printers in the metal casting industry sector.

Analisis Overall Equipment Effectiveness (OEE) pada Mesin Caterpillar Type 3512B

PT. PLN (Persero) ULPLTD Bagan Besar PLTD Bengkalis where the diesel engine is the prime mover. In this case, the role of engine maintenance is needed so that there are no obstacles in the process of distributing community power, especially for Bengkalis Island. Therefore, it is necessary to identify to measure the level of effectiveness of the work of the machine by using the Overall Equipment Effectiveness (OEE) method. Overall Equipment Effectiveness (OEE) is a method of measuring the overall effectiveness of a production machine that involves measuring the level of effectiveness of time, the level of machine performance, and the level of quality of products produced. Measuring the level of work effectiveness of the Caterpillar Type 3512B engine with the Overall Equipment Effectiveness (OEE) method at PT. PLN (Persero) ULPLTD Bagan Besar PLTD Bengkalis in the December 2018 - March 2019 period the results obtained do not meet the value of the Word Class Ideal OEE with a percentage value below 85%.

Karakterisasi Unjuk Kerja Mesin 100 CC dengan Bahan Bakar Syngas

Gasification is a process of converting carbon-containing compounds to convert both liquid and solid materials into fuel-capable gas (CO, H2, CO2, CH4, and H2O) through the combustion process with limited air supply. Gasification that we have known so far is gasification with coal feed and agricultural waste, but gasification with livestock waste feed has never been done. In this study the gasification feed material used horse dung biomass with a gas agent in the form of oxygen. The purpose of this study was to determine the effect of oxygen flow rate (4 variations namely 10, 15, 20 and 30 lt / min) in the process of gasification of horse dung (produced 4 fuels namely syngas A, syngas B, syngas C and syngas D) on the performance capabilities of a 100 cc engine. The stages of the research carried out were drying feed material, gasification process, syngas storage and testing on a 100 cc engine with various variations of rotation (4 variations namely 1500, 2500, 3500 and 4500 rpm). The results obtained from this study are the highest torque and effective power obtained in syngas A fuel for various engine speeds. At 4500 rpm, a torque of 6.7 Nm is obtained, while an effective power of 3156 Watts is used to test engine results using Syngas A fuel.

Analisis Pengujian Dry Gas Seal Type 28AT Tandem untuk Meningkatkan Reliability Dry Gas Seal di Kompresor Setrifugal

Dry gas seal testing is one of the stages in the repair and maintenance of dry gas seals because without testing dry gas seals will have fatal consequences, which can cause more severe damage to the compressor and repair of humans and the environment. In the operation and maintenance of centrifugal compressors, especially gas compressors, there is often damage to dry gas seals or even if they are not damaged dry gas seals must be kept in a health check so that they can be used optimally and their reliability can be improved. In conducting a health check or repairing dry gas seal, one of the determinants of success is through static and dynamic testing using the DGS test rig or the other. Therefore it is very important in testing this dry gas seal that the author tries to learn how to complete the tests that must be considered in the testing procedure. In this study it can be concluded that the maximum speed used reaches 11429 rpm, when compared to the procedure is 1 - 1,225 x rpm in the compressor then the rotation obtained according to the procedure is (1,225 x 10000 = 12250 rpm maximum), with conditions 11429 rpm already fulfilling standard and is still within tolerance of testing rounds.

Desain Sistem Mekanik pada Transmisi Motor Matik untuk Keselamatan Pengendara

The vehicle market in Indonesia, especially motorbikes is very large, it is estimated that the growth of motorbike vehicles will reach 6 million per year. Recently, more than 50 percent is dominated by automatic motorcycles and the market increase significantly. This is because automatic motorcycles can be easily ridden. There are some weaknesses with this transmission system, among them is there is no engine brake when the road is in downhill condition. The motor will easily run when the gas throttle is pressed. This paper discusses the design of a mechanical system on the automatic transmission that is able to prevent mistake on procedures that causes accidents. To achieve this goal, it is necessary to do several steps, including reviewing the existing design, determining the new system, designing the system, manufactured and testing. Experiment results shows that the current motorcycles automatic transmission system can be replaced with a mechatronic system with special linkage mechanism to control ratio change.

Modification of Digital Oil Pressure Measurement Equipment using Bluetooth Technology

PT United Tractors Tbk Jakarta workshop held a lot of Machine Inspection Programs for Komatsu units. During the implementation of the Machine Inspection Program (PPM) the machine inspection program is one part of the maintenance that is carried out periodically to obtain accurate data on the condition of the equipment at the time by carrying out checks and adjustments using measurement methods and diagnostic instruments The use of a pressure gauge is still using manual and has a measurement distance that is still limited, if workers or mechanics are not equipped with sufficient knowledge then the pressure gauge will have the potential for error in use and the selection of a pressure gauge is not appropriate to the pressure gauge directly connected to the hydraulic pressure through the hose then the work process ppm is not enough 1 manpower. Therefore it is necessary to modify a digital pressure gauge that has a wide range of scales, in addition a wireless connection is needed to enable the operation of the unit and measurements are made 1 manpower and Bluetooth is one of the right choices in addition to the reach can be met in an application not too difficult so that readings measurement results can be connected directly via mobile.

Analisis Ketebalan Lapisan pada Pengecatan Baja Karbon Rendah menggunakan Metode Respons Permukaan

The number of vehicles has increased every year. This increase was accompanied by an increase in the number of accidents that occurred. Accidents that occur result in damage to vehicles so that repainting is needed. Painting is an effort made by applying paint in liquid form on the surface of an object to create a layer on the surface of the object. Painting serves to protect and improve the appearance of a surface. The purpose of this study is to determine the effect of a combination of parameters that can produce maximum thickness values. The experimental design used in this study is a surface response method with three parameters where each parameter has three levels. The parameters chosen were spraying distance (110 mm, 130 mm, 150 mm), composition between paint-thinner (1/1.6, 1/1.4, 1/1.2), and pressure (3.5, 4.5, 5.5). The painting process is carried out with the help of a paint test demonstrator. The painting results are dried in the oven and then measured using a thickness gauge. The measurement data is processed using the help of Minitab software and the estimator equation for thickness is obtained. The parameters with the greatest influence in this study are the distance of spraying with a distance coefficient of 2.258. Painting with the highest average value of thickness occurred in the fifteenth experiment with a thickness value of 39.9 micron. The thickness is obtained by variable variations of 130 mm distance, paint-thinner 1/1.4 composition and 4.5 bar pressure.

PEMELIHARAAN MESIN DISC MILL SENTRA PETERNAKAN RAKYAT (SPR) CINAGARBOGO

Sentra Rakyat Rakyat (SPR) is a collection of cattle breeders in the Subang Regency area. SPR aims to raise beef cattle and provide ruminant feed. Ruminant feed made from corn hump waste. The disc mill machine is used in the process of destroying corn lumps into flour, flour from the results of this corn hump will be combined with other components to form a ruminant feed for cattle feed. The process of making feed is disrupted because the disc mill machine is damaged. This study aims to detect damage to the engine and clasification maintenance of disc mill machines using the Inspection, Medium Repair, Small Repair, and Overhaul (ISMO) methods. The method used in data collection is in the form of interviews and observations. Data is analyzed qualitatively description. The results of this study are (1) machine damage, namely the disc mill cutting blade allowance caused by the destruction of the engine shaft bearing; (2) More maintenance is needed on filter sections, cutting blades, crankshafts, v-belts and bearings.

ANALISIS KETAHANAN ABRASI MATERIAL OUTSOLE POLYURETHANE (PU) & NITRILE BUTADINE RUBBER (NBR) PADA SAFETY SHOES CHEETAH DI PT. X

Improved quality, strength and life time in terms of abrasion resistance on safety shoes outsole Cheetah material where the process use of some material has decreased in quality, besides due to usage factors, maintenance factors, and some of these materials also experience problems during use. This study is done to determine the abrasion resistance of each Outsole Polyurethane (PU) material and Nitrile Butadiene Rubber (NBR). Abrasion resistance test on the material method used the DIN Abrasion tester. Retrieval of data on outsole material was carried out on the outsole material with new conditions and that has been used in the field for a period of 1 year with a method of measuring abrasion resistance index and density of material. Calculation of average abrasion resistance for new Polyurethane (PU) type was 37 , 11 mm3 / year, while the average abrasion resistance for Polyurethane (PU) type that has been used for 1 year was 33.19 mm3 / year so that the difference is 3.92 mm3 / year or about 11% quality decrease of abrasion resistance. The average abrasion resistance with the new Nitrile Butadiene Rubber (NBR) type was 108.26 mm3 / year, the average abrasion resistance for Nitrile Butadiene Rubber (NBR) type with conditions already used in 1 year period was 107.44 mm3 / year so that the difference is 0.82 mm3 / year or about 1% decrease in quality decrease of abrasion resistance. Abrasion tolerance limits that have been set according to the SOP (Standard Operational Procedure) against abrasion resistance if SG ≥ 0.9 then the Abrasive Max is 150 and if SG ≤ 0.9 Then the Abrasive Max is 250.