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Pengaruh Perlakuan Alkali (NaOH) Terhadap Morfologi dan Kekuatan Tarik Serat Mendong Witono, Kris; Irawan, Yudy Surya; Soenoko, Rudy; Suryanto, Heru
Jurnal Rekayasa Mesin Vol 4, No 3 (2013)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (692.104 KB)

Abstract

Chemical modification on fiber by using Natrium Hydroxide (NaOH) solution directly affect to the fiber structure such as changing the chemical composition of the fiber and improve the performance of natural fiber as the composite reinforcement. The purpose of this study is to inverstigate the effects of NaOH solution to the tensile strength and the mofology of Mendong fiber. The concentration of NaOH solution were 2,5% v/v; 5% v/v; dan 7,5% v/v on this experiment. Mendong fiber was soaked for 2, 4 and 6 hours in NaOH solution. The temperature on this study was 26 o C. The tensile strength of Mendong fiber was increased by increasing the NaOH solution concentration and duration of soaking after exceed the concentration of NaOH solution and duration of soaking the tensile strength would be decreased. The highest tensile strength was 497,34 MPa with NaOH solution concentration 5% v/v and the duration of soaking, 2 hours. The roughness of Mendong fiber by soaking in NaOH solution was higher than without soaking in NaOH solution. Soaking on the highest concentration of NaOH solution caused the highest roughness.Keywords: NaOH solution, Mendong fiber, tensile strength, roughness.
PENGARUH MODEL SUDU OVERLAP DAN HELIX PADA PROSES INISIASI PUTARAN TURBIN SAVONIUS Witono, Kris; Nasir, Moh.; Faizal, Elka; Wicaksono, Hangga; Pranoto, Bayu
Otopro Vol 15, No 1 (2019)
Publisher : Jurusan Teknik Mesin Universitas Negeri Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26740/otopro.v15n1.p27-31

Abstract

This research proposes a new model of overlap and helix blade shape. The overlap shape of the blades gives room to the air flow shortly after pounding the blades. Air flow direction is strived to be able to push the next blade so that the process of the turbine blade rotation becomes more effective. While the helix model is expected to produce a more efficient turbine rotation due to its multilevel shape. The wind speeds tested were 2 m / s, 4 m / s, and 6 m / s. Turbine speed rotation data retrieval is carried out at each additional time. The overlap blade has a greater angular velocity value of 9.4 rad / s at 2 m / s wind speed, 21.9 rad / s at 4 m / s wind speed, and 29.8 rad / s at 6 m / s wind speed.Turbines with multilevel helix blades have a higher level of stability compared to overlap blades. This is because there are two levels of turbine blades which have an angle difference of 600 which can receive more stable wind collisions. However, due to the smaller cross-sectional area of the helix blade turbine (ie 50% of the overlap blade) the effective impact area on the blade is also getting smaller. So that the energy that can be converted is also relatively smaller than the overlapping blade.
APLIKASI HOME SOLAR SYSTEM SEBAGAI PENERANGAN UNTUK TPQ AL-MURTADHO DI KOTA MALANG Asrori, Asrori; Harijono, Agus; Faizin, Akhmad; Dani, Agus; Kriswitono, Kriswitono
Jurnal Penelitian dan Pengabdian Kepada Masyarakat UNSIQ Vol 8 No 1 (2021): Januari
Publisher : Lembaga Penelitian, Penerbitan dan Pengabdian Masyarakat (LP3M) UNSIQ

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32699/ppkm.v8i1.1499

Abstract

Lokasi TPQ-Al Murtadho terletak di RW 01, Wonokoyo, Kedungkandang, Kota Malang. Bangunan semi permanen ini didirikan secara swadaya oleh warga setempat. Selain berfungsi sebagai taman pendidikan Al-Quran (TPQ), bangunan ini juga dimanfaatkan untuk tempat musyawarah warga. Sistem penerangan yang murah dan mudah sangat relevan untuk diterapkan pada bangunan tersebut. Oleh karena itu dalam PkM ini dilakukan pelatihan singkat dan pemasangan sistem penerangan bertenaga surya (home solar system). Kegiatan yang dilakukan bersama pemuda karang taruna ini berlangsung selama dua hari. Pelatihan berupa presentasi mengenai listrik tenagasurya, yang dilanjutkan dengan perakitan dan pemasangan instalasi panel surya di TPQ Al-Murtadho. Hasil PkM adalah paket listrik tenaga surya yang terdiri dari : 1 unit panel surya; 1 unit solar charger controller; 1 unit baterai; 3 lampu LED dan peralatan aksesoris. Panel surya yang digunakan adalah 100 WP (Watt Peak) artinya daya maksimum yang mampu dibangkitkan oleh panel surya dalam 1 jam adalah 100 Watt. Jika sinar matahari dalam kondisi normal (cerah) diasumsikan 5 jam, maka panel surya mampu menghasilkan listrik sebesar 500 Wattjam. Sehingga dengan energi tersebut akan mampu untuk menyalakan lampu dengan daya 9 Watt pada 3 titik selama 9-10 jam.
Pengaruh Model Sudu Overlap dan Helix pada Proses Inisiasi Putaran Turbin Savonius Witono, Kris; Nasir, Moh.; Faizal, Elka; Wicaksono, Hangga; Pranoto, Bayu
Otopro Vol 15, No 1 (2019)
Publisher : Jurusan Teknik Mesin Universitas Negeri Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26740/otopro.v15n1.p27-31

Abstract

This research proposes a new model of overlap and helix blade shape. The overlap shape of the blades gives room to the air flow shortly after pounding the blades. Air flow direction is strived to be able to push the next blade so that the process of the turbine blade rotation becomes more effective. While the helix model is expected to produce a more efficient turbine rotation due to its multilevel shape. The wind speeds tested were 2 m / s, 4 m / s, and 6 m / s. Turbine speed rotation data retrieval is carried out at each additional time. The overlap blade has a greater angular velocity value of 9.4 rad / s at 2 m / s wind speed, 21.9 rad / s at 4 m / s wind speed, and 29.8 rad / s at 6 m / s wind speed.Turbines with multilevel helix blades have a higher level of stability compared to overlap blades. This is because there are two levels of turbine blades which have an angle difference of 600 which can receive more stable wind collisions. However, due to the smaller cross-sectional area of the helix blade turbine (ie 50% of the overlap blade) the effective impact area on the blade is also getting smaller. So that the energy that can be converted is also relatively smaller than the overlapping blade.
Pengaruh Variasi Lip Thickness Pada Nozzle Terpancung Dengan Swirl Terhadap Kestabilan Api Difusi Concentric Jet Flow Kris Witono; Akhsanu Takwim
Jurnal Energi dan Teknologi Manufaktur Vol 1 No 01 (2018)
Publisher : Polinema Press, Politeknik Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33795/jetm.v1i01.10

Abstract

One of the factors that affect flame diffusion characteristics is the geometry of fuel nozzles in the installation of the combustion system. The nozzle shape greatly affects the turbulence that occurs between fuel and air. This process causes the formation of flow recirculation zones. This process thus produces homogeneous mixing and obtains near perfect combustion. The recirculation zones are zones arising from breaking the flow rate. So as to cause a vortex and backflow around the tip of the nozzle. It is this feedback which inhibits and simultaneously suppresses the flame so that the flow rate of the fuel mixture and the air is maintained lower or equal to the flame velocity. In this study, lip thickness variations in nozzles were used with swirls with variations of 0, 4, 8, 12, and 16 mm to determine flame stability of concentric jet flow diffusion. Fuel velocity and air are varied to obtain flame stability data. In addition, to support and reinforce the results obtained from this study, direct photograph and shadowgraph methods are used to obtain flow pattern visualization. The result of the research shows that the stability of flame concentric jet flow diffusion has increased along with the decreasing of lip thickness in nozzle. The largest flame stability area is obtained in 4 mm thick lip thickness.
ANALISIS PERBANDINGAN SIFAT MEKANIS PIPA TEMBAGA AC BARU DAN BEKAS R.N. Akhsanu Takwim; Kris Witono; Bambang Irawan
INFO-TEKNIK Vol 19, No 2 (2018): INFOTEKNIK VOL. 19 NO. 2 DESEMBER 2018
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/jit.v19i2.158

Abstract

In the repair of the installation of air conditioners or refegeration are oftenfound referigeran (ACR) tube that must be replaced because the old copper tubeleaked on the connection. Replacement is done because the repair of the connectionby cutting and flaring the connection usually fails in the form of a tear on the flaredpart.The cause of flaring failure in the used air conditioner tube by testing themechanical properties and the microstructure of the material and compared with themechanical properties and the microstructure of the new tube material.Knowing thecauses of the failure can be searched for the prevention and repair solutions so thatthe old tube can be used without replacement.The tensile test results showed that the average ultimate strength of the usedACR copper tube has increase in strength of 18188.65 N/mm2 comparing with theultimate strength of the new copper tube which was only 14615.15 N/mm2.The microVickers test results show the same phenomenon from the tensile test results, wherethe hardness value of used ACR tube has 42.7 HV while the new ACR tube is 37.8HV.Microstructure testing with SEM shows the changing in grain structure from alongitudinal shape with a large enough grain size and tenuous in a new tube, to moreflat and dense longitudinal grain structure for used tube.
PENGARUH TEMPERATUR ANELING TERHADAP KEKERASAN DAN KEKUATAN PIPA TEMBAGA AC BEKAS R. N. Akhsanu Takwim; Kris Witono; Pondi Udianto
INFO-TEKNIK Vol 20, No 2 (2019): INFOTEKNIK VOL. 20 NO. 1 DESEMBER 2019
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/infotek.v20i2.7717

Abstract

During the installation process, copper pipes for air conditioning will experience a very large deformation due to straightening and bending following the installation path. Hardening strains occur that result in changes in mechanical properties in this case decreases ductility making it difficult to do the connecting process with flaring. Studies need to be carried out to restore the mechanical properties of copper pipes that have been used, including the heat treatment process on copper pipes, so that used copper pipes have a better benefit value than having to be recycled. The temperature of the heat treatment is varied from 400oC, 500 oC and 600 oC. Tensile test results show that at annealed temperature of 400 oC has the highest tensile strength of 125.81 N / mm2 and proportional limit stress of 40.52 N / mm2. Whereas in the microhardness test, the highest hardness occurs also at annealed temperature of 400 oC which is equal to 50.8 HV.
EFFECT OF HEAT TREATMENT TEMPERATURE ON THE FORMATION OF DUAL PHASE STEEL AISI 1005 HARDNESS AND FLEXURE STRENGTH CHARACTERISTICS OF MATERIALS Kris Witono; Lisa Agustriyana; Agus Setiawan
INFO-TEKNIK Vol 16, No 1 (2015): INFOTEKNIK VOL. 16 NO. 1 2015
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/infotek.v16i1.208

Abstract

Any material intended for automotive use, especially in the body panels must have the criteria able to form (formable), weldability (weldable), coatable (resistant to corrosion) and able to be repaired (repairable). One group of materials that meet all the above requirements are dual phase steel. To form a dual phase steel can be done through a process of heat treatment.The purpose of this study was to determine the effect of heat treatment temperature on the formation of a dual phase of the material hardness properties and flexural strength steel.The method used is a variation of the process of heat treatment at temperature 7300C, 7500C, 7700C, 8000C, 8500C, 9000C.The results of the study include the establishment of dual phase steel can improve the hardness of AISI 1005 steel with a carbon content of 0.033% C, the highest value of flexural strength is obtained at a temperature of 770 ° C treatment that is 1.98 kg / mm2 with 223.08 HV hardness values. The hardness and flexural lowest strength obtained at the treatment temperature of 900 ° C is 197.14 HV and 1.15 kg / mm2 and dual phase steel with optimum mechanical properties obtained at a temperature of 770 ° C. Key word : heat treatment, dual phase, hardness, flexure strength
PENGARUH VARIASI POSISI PEMASANGAN DAN ARAH ALIRAN FLUIDA TERHADAP KINERJA VENTURI VAKUM R. N. Akhsanu Takwim; Kris Witono
INFO-TEKNIK Vol 20, No 1 (2019): INFOTEKNIK VOL. 20 NO. 1 JULI 2019
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/infotek.v20i1.6956

Abstract

A liquid fluid flow that is driven by a centrifugal pump past the ventury channel needed to produce the vacuum conditions at the ventury vacuum pump. The amount of vacuum pressure produced by ventury is influenced by the increase of flow rate due to the channel cross section that follows the Bernoulli principle. The flow rate on the channel is affected by the discharge generated by the pump that follows the law of continuity. In addition to speed, the pressure of channel input is also a variable that affects ventury vacuum pressure. Pressure losses and flow discharge caused by the connection or turn of the pipe arising from the installation design, will affect the performance of the Setrifugal pump in the form of discharge flow and pressure that ultimately strongly affects the rally Venturi vacuum work. Therefore, it is necessary to evaluate the influence of the design of the istalation associated with the position of ventury mounting and the direction of the flow to the pressure and discharge of the vacuum to be the primary purpose of this research so that the variables are obtained The performance of a ventury vacuum pump. In this research the placement of vacuum ventury in several positions, namely vertical position, horizontal position and tilt position 45o. Then measured parameters are occurring, such as discharge fluid flow, liquid fluid pressure and vacuum pressure occurring on the pipe. From this study obtained optimum performance on the installation with a sloping ventury position of 45o with the direction of the downward flow, which resulted in the lowest vacuum pressure of-65 CmHg with ventury suction flow of 33.01 liters/minute.
LAJU PENDINGINAN PENGELASAN BAJA CARBON SEDANG PADA TEMPERATUR LINGKUNGAN BERBEDA R. N. Akhsanu Takwim; Kris Witono; Pondi Udianto
INFO-TEKNIK Vol 21, No 1 (2020): INFOTEKNIK VOL. 21 NO. 1 JULI 2020
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/infotek.v21i1.8964

Abstract

The quality of welding results is influenced by the shape of the microstructure of the welding material especially in the HAZ region. The shape of the welding microstructure is largely determined by the cooling rate of the weld material. The cooling rate of the weld is greatly influenced by the heat input from the arc and the ambient temperature. This study aimed to determine the effect of different environmental temperatures on the cooling rate of welding results. Welding of GMAW fillets on medium carbon steel plates S50C, with variations in welding currents 90 A, 100A and 110A and carried out at variations in environmental temperature of 15oC, 10oC and 5oC. Temperature data on the middle, welding part is taken with a digital thermometer to compare the effect of each variable. The test results show that the greater the welding current, the slower the cooling rate. Similarly, an increase in ambient temperature causes a decrease in the weld metal's cooling rate.