KINEMATIC ANALYSIS AND SUBSTANTIATION OF THE PARAMETERS OF A SPIRAL-SCREW WORKING UNIT OF A SOIL PROCESSING MACHINE

To improve the quality of pre-sowing soil tillage in the Republic of Tatarstan, a tillage implement has been developed, which, unlike other designs, contains a helical spiral and needle ellipsoid disks coaxially mounted on a horizontal shaft. Passive helix creates a compacted seed bed at the depth of seed placement; needle ellipsoidal disks are active and provide mulching of the surface soil layer. A preliminary analysis of the processes of interaction of the working unit with the soil is possible on the basis of the parametric equations of motion of individual points of the cutting edges of the helical spiral, as well as expressions for determining their speeds and accelerations. The design parameters selected during the calculation and design of the proposed rotary combined tool should ensure that the helical spiral enters the soil with sliding. Otherwise, the traction resistance of the unit increases. To justify the basic design parameters of a spiral-screw working unit, preliminary construction of theoretical dependences is also necessary. According to the calculation results, the points of the cutting edge of the helical spiral make a complex movement in space when the gun moves. The components of the speed and acceleration of these points are variable parameters, which contributes to the active crumbling of the soil and the destruction of its lumps. The optimal design parameters of the working unit of the gun: the diameter of the helical spiral is 0.470 m; the angle of inclination of the helical spiral (the angle of the helix) - 10 ° ... 25 °; the angle of inclination of the large side of the strip to the generatrix of the cylindrical surface that describes the helical spiral is 25 ° ... 30 °

Karakteristik Koefisien Serap Suara Material Concrete Foam Dicampur Serat Tandan Kosong Kelapa Sawit (TKKS) dengan Metode Impedance Tube

Perkembangan teknologi di dunia pada saat ini sangat cepat pertumbuhannya, hal ini berbanding lurus terhadap perkembangan peralatan transportasi, industri, informasi, komunikasi maupun hiburan yang menimbulkan kebisingan sehingga mengganggu aktivitas sehari-hari, kenyamanan lingkungan dan kesehatan pada manusia. Suara menjadi bagian dalam kehidupan sehari-hari yang kita kurang sadari fungsi dan eksistensinya. Energi suara datang pada suatu bahan akan dirubah menjadi energi getar (vibrasi) atau energi panas. Bahan yang mampu menyerap suara pada umumnya mempunyai struktur (1) berpori atau (2) berserat. Penelitian ini bertujuan untuk mendapatkan karakteristik serap suara material akustik menggunakan concrete foam dicampur dengan serat tandan kosong kelapa sawit (TKKS). Concrete foam dibuat dengan cara pencampuran bahan semen, pasir, serat TKKS, air, dan foam agent pada alat horizontal shaft mixer kemudian dituangkan pada cetakan. Pembuatan spesimen menggunakan teknik penuangan/pengecoran ke dalam cetakan plat besi dengan proses perendaman selama 7 hari dan proses pengeringan selama 21 hari. Spesimen material concrete foam dan mortar dilakukan pengujian serap suara dengan metode impedance tube. Berdasarkan pengujian impedance tube sesuai dengan ISO 10534-2:1998 bentuk spesimen adalah silinder ukuran Ø112×10mm, Ø112×30mm, dan Ø112×50mm. Pengujian material concrete foam diperkuat serat TKKS sebesar 4% dengan bentuk silinder ukuran Ø112×10mm diperoleh nilai koefisien serap suara terbaik pada daerah frekuensi menengah 500Hz–2000Hz yaitu 0,958 pada frekuensi 1000Hz, material ini menunjukkan lebih mampu melakukan penyerapan terhadap energi suara yang datang pada permukaan material dibandingkan material mortar memiliki nilai koefisien serap suara terbaik pada daerah frekuensi rendah 0Hz–500Hz yaitu 0,818 pada frekuensi 125Hz dengan bentuk silinder ukuran Ø112×30mm.

INFLUENCE OF A NUMBER OF IMPACTS OF LOW-SPEED MIXER BLADES ON CONCRETE QUALITY BEING PREPARED

The paper presents purpose equations describing the uneven mixing depending on the number of the mixer blade impacts per unit of concrete weight as well as the weight of the mixture that have an impact on blades of the slow-speed mixer. Based on the literature review and analysis of the mixing process conducted in the Samara State Agricultural Academy, the design of the blade mixer was developed. The mixer consists of a body where there is a horizontal shaft with working bodies, made in the form of radial blades of helical shape. There are received equations that allow determining the concrete uniformity depending on a number of the impacts of the mixer blades per unit of the concrete weight as well as on the concrete weight that act on the blades of the slow-speed mixer. The power function is adequately described by the experimental results of 98 % confidence probability. In the studied areas of changes in independent factors rational values of the number of impacts per unit of the concrete weight is not less than 800 PCs/kg, as well as the concrete weight having impact on the blade of the slow-speed mixer is not more than 0,001 kg/PC.

Pengoperasian dan Perawatan PLTMH pada Pembangkit Listrik Mikro Hidro (PLTMH) di Sungai Batang Geringging Kota Padang

Water turbine is a tool to convert the potential energy of water into mechanical energy, this mechanical energy is then converted into electrical energy by a generator. Crossflow turbines are radial, small pressurized turbines with tangential injection from fan rotation with a horizontal shaft. The flow of water flows through the pipe entrance, and is arranged by a propeller and into the turbine fan rotation. After the water passes through the turbine fan rotation, the water is at the opposite fan rotation, thus providing additional efficiency. Finally, water flows from the casing either freely or through a tube under the turbine so that it rotates and turns the generator so it can produce electricity. Maintenance of PLTMH is carried out namely preventive maintenance such as; cleaning, lubrication and periodic checks. Maintenance corrections are carried out with the aim of being able to maintain the PLTMH component. Predictive maintenance of a treatment carried out in accordance with the conditions of the PLTMH and predicting damage that will occur in PLTMH

PERANCANGAN PROTOTYPE ALAT PENGURANG KADAR AIR PADA MADU KAPASITAS 5 LITER

The quality of Honey must meet the requirements set by the Indonesian National Standard (SNI) in 2004. In the standard set, the enzyme diastase function is at least 3 DN, hydroxymethylfurfural (HMF) maximum 50 mg / kg, maximum air content is 22% b / b, sugar reducing at least 65% b / b,asucrose maximum 5% b / b, acidity maximum 50 milliecivalents / kg, solids not up to maximum 0.50% b / b, maximumAash content 0.50% b / b (BSN), 2004) To meetAthese standards designedAa tool that willAreduce the air content in honey without damaging it as it is vaccinated at -70 -70 bar with temperatures below 40 ° C. With the results of the balance shows: (1) electric motor with power ¼ HP with 1400 rpm rotation. (2) V-belt transmission with large outside pulley dimensions = 231.3 mm, small outer plley = 104 mm. Using a v-belt with no. 44 in / 1118 mm. Horizontal shaft with dimensions of large pulley shaft diameter = 18 mm and small pulley shaft diameter = 15 mm. (3) Using a gearbox damper with a ratio of 1:40. (4) Stirrer shaft with 304 grade stainless steel material with a length of 975 mm and a shaft diameter of 40 mm. (5) Stirrer impeller with six blade impeller type with dimensions of diameter 1667, mm and thickness of 3 mm. (6) Vessels with cylindrical types and having a thickness of 2.5 mm, a diameter of 500 mm and a length of 500 mm. With an ellipsoid head type with dimensions of 520 mm in diameter, 125 mm in height and 2.5 mm in thickness. (7) Frame with a profile of mild steel profile dimension dimensions of 40 mm x 40 mm x 2.5 mm.

Vibration Study for a Subassembly – Part of Hydraulic Turbines

A common problem with hydraulic turbines is the rupture of turbine horizontal shaft in the area between the rotor and its bearing, caused by different stresses [1], as well as problems caused by excessive bearing wear, vibration caused by instability of lubricant film from bearings, lubrication supply interruption of hydrodynamic bearings, gripping, decrease of bearing stiffness due to fatigue of supporting structures. In addition, during operation, vibration appear depending on exciter forces or bearing type. In present paper we present an analysis of vibrations measured on a subassembly found at hydraulic turbines. For the experimental subassembly was used a straight-lined shaft, having variable cross-section, and a sliding type bearing. The tests were made for bearings of different dimensions and materials. Vibrations were measured on two axes for established case studies and results were compared.