Abdulkadir Gullu - Academia.edu (original) (raw)

Papers by Abdulkadir Gullu

Materials & Design, 2006

In this study, AISI 304 stainless steel and St 52 carbon steel have been cut by plasma arc and th... more In this study, AISI 304 stainless steel and St 52 carbon steel have been cut by plasma arc and the variations of structural specifications occurred after cutting has been investigated. According to the experimental results, it has been seen that burning of particulars and distribution amount were increased when the cutting was performed using the speeds which are upper or lower limits of the ideal cutting speeds proposed by the manufacturer of the machine tool. Moreover, it was determined that the hardness from the outer surface to the core decreased, while the hardness near to the outer surface which affected by the high temperature occurred during cutting increased.

Politeknik Dergisi, 2007

ÖZET CNC işleme merkezlerindeki eğrisel hareketler dairesel interpolasyon hareketleri ile gerçekl... more ÖZET CNC işleme merkezlerindeki eğrisel hareketler dairesel interpolasyon hareketleri ile gerçekleştirilmektedir. Bu hareketlerdeki hatalar dairesellik hatası olarak adlandırılmaktadır. Bu çalışmada, dairesellik hatası ölçüm sistemi tanıtılmıştır. Dairesellik hatası tarif edilerek, bu hatanın değerlendirildiği algoritmalar tanıtılmıştır. Ayrıca bu sistemdeki ölçüm cihazları, ayrıntılı yayın taraması ile analiz edilerek tartışılmıştır.

Solid State Phenomena, Jun 5, 2013

ABSTRACT

Politeknik Dergisi, 2008

Bu çalışmada, AISI 316 paslanmaz çeliğin takma uçlu parmak freze ile işlenirken, kullanılan kesic... more Bu çalışmada, AISI 316 paslanmaz çeliğin takma uçlu parmak freze ile işlenirken, kullanılan kesici uç üzerindeki talaş kırıcı formun kesici kenar üzerindeki aşınmaya ve yüzey pürüzlülüğüne etkisi incelenmiştir. Bunun için kesme derinliği sabit tutularak, üç değişik talaş kırıcı formlu takım ve üç farklı kesme hızı (180, 225, 270 m/min) kullanılmıştır. Yapılan deneysel çalışmada, kullanılan kesici takımlardan ERGC kodlu takımın diğer takımlardan daha iyi aşınma ve yüzey pürüzlülüğü sonuçları verdiği ortaya çıkmıştır.

Solid State Phenomena, 2009

Statistic based predictive modelling is often used for structures which are especially difficult ... more Statistic based predictive modelling is often used for structures which are especially difficult to control and model. The modelling of hydraulic systems is challenging as they lose their stability due to the nonlinear parameters such as temperature changes, compressibility, leakages, load and friction. In the study, circularity error of curvilinear motions driven by this system is statistically analysed at the

zet Bu çalışmanın amacı, destekleyici yürüme cihazında bulunan kalça parçasının tasarımı ve anali... more zet Bu çalışmanın amacı, destekleyici yürüme cihazında bulunan kalça parçasının tasarımı ve analizidir. Bu mekanizma tam ya da kısmi yürüme engelliler için çok faydalıdır. Ayrıca kalça parçasın gerçek ortamda uygulanan yükler altında ne türlü tepki göstereceği sanal bir ortamda simüle ve analiz edilmiştir. Analizler için SolidWorks benzetim programı, en pratik çözümlerden biri olarak kullanılmıştır. Kalça parçasının Gerilim, deformasyon, yer değiştirme ve emniyet faktörü gibi analizleri gerçekleşmiştir. Buna ek olarak çeşitli bilgiler bu yöntemle hesaplanmaktadır. Bu yöntemde kalça parçasının imalatı uygun bir durumda yapılmıştır. Böylece hem zaman hem de malzeme israfı önlenmiştir. GİRİŞ Parçaların gerçek ortamda nasıl bir yük altında olacakları ve ne türlü tepki gösterecekleri SolidWorks 'un simülasyonu yazılım paketinde analiz yapılarak incelenmiştir. Yapılan mühendislik hatalarından doğan zararları ve zaman israfını önlemek ve güvenilir bilgiye erişmek için bilgisayar destek...

European journal of dentistry, 2008

The aim of this study was to investigate the effects of fiber-reinforced resin burs on the surfac... more The aim of this study was to investigate the effects of fiber-reinforced resin burs on the surface roughness of a nanofilled composite. Average surface roughness values (Ra, mum) were measured using a surface profilometer and surface textures after finishing procedures were evaluated using a scanning electron microscope (SEM). Thirty cylindrical specimens were prepared using sectional teflon molds. A nanofilled composite was chosen. After the preparation specimens were divided into three subgroups randomly. After profilometric measurements, representative samples of the mentioned finishing procedures were selected and SEM analyses were carried out. Mylar strip group was statistically different from the other two groups (P<.05). The smoothest surfaces occurred when composite resin samples were light cured against the strips. On the other hand there was no statistical difference between fiber-reinforced resin burs and Sof-Lex discs (P>.05). For fiber-reinforced resin burs scratc...

European journal of dentistry, 2012

The aim of this study was to evaluate surface roughness and hardness of a nanofiller GIC, a resin... more The aim of this study was to evaluate surface roughness and hardness of a nanofiller GIC, a resin-modified GIC, three conventional GICs, and a silver-reinforced GIC. For each material, 11 spcecimens were prepared and then stored in distilled water at 37 °C for 24 h. The surface roughness of 5 specimens was measured using a surface profilometer before polishing and after polishing with coarse, medium, fine, superfine aluminum oxide abrasive Sof-Lex discs respectively. The hardness of the upper surfaces of the remaining 6 specimens was measured with a Vickers microhardness measuring instrument. All tested GICs showed lower surface roughness values after the polishing procedure. Surface finish of nanofiller GIC was smoother than the other tested GICs after polishing. This was followed by resin-modified GIC, Fuji II LC; then silver-reinforced GIC, Argion Molar, conventional GICs, Aqua Ionofil Plus, Fuji IX, and Ionofil Molar, respectively. The result of the hardness test indicated that ...

Materials & Design, 2006

In this experimental study some statistical calculations have been made to eliminate quality prob... more In this experimental study some statistical calculations have been made to eliminate quality problems such as undesirable tolerance limits and out of circularity of spherodial cast iron parts during machining. X-R control charts have been constructed on the data obtained from this manufacturing to discover and correct assignable causes, so that the machine capability (Cp) and the process capability (Cpk) can be determined.

Materials & Design, 2006

In this experimental work, the influence of silane coated glass fibres added to polypropylene (PP... more In this experimental work, the influence of silane coated glass fibres added to polypropylene (PP) and polyamide 6 (PA6) plastics was investigated. These plastics were reinforced with (15 and 30 wt%) silane coated glass fibres. For this purpose, a die was designed and manufactured to produce tension and notched impact species using various injection parameters. Based on the results of this work, which investigates the influence of fibre reinforcement and injection parameters on the tensile strength and impact strength, PP and PA6 plastics reinforced with glass fibre exhibited improvement in their mechanical strength with the fibre reinforcement. However, improvement in the mechanical strength did not show a linear relationship with the fibre weight fraction on account of inhomogeneous fibre distribution and fibre fracture. In addition, tensile strength increased with increasing injection feeding zone temperature and decreased with increasing injection speed and extruder screw speed.

Sadhana, 2012

ABSTRACT In this study, a twin-axis gantry has been structured to examine hydraulic driven positi... more ABSTRACT In this study, a twin-axis gantry has been structured to examine hydraulic driven positioning skills of the curvilinear motions based on ISO 230-4 standard entitled ‘Circular tests for numerically controlled machine tools’. The system is controlled by a path and position control module of a PLC device. As a result of the experiments conducted based on the full factorial design, the effects of piston diameter, feed rate, radius and their two-way interactions on the circularity error are determined through analysis of variance. Accordingly, minimum circularity error is obtained with the piston diameter of 63 mm, inertia load of 12.5 kg, radius of 5 mm and feed rate of 50 mm/min as 0.345 mm. Circularity error increases with the increase of inertia load, radius and feed rate, and declines with the increase of piston diameter. Lastly, piston diameter has the greatest effect on the circularity error change and followed by radius, feed rate, piston diameter–radius, radius–feed rate, piston diameter-feed-rate, inertia load, piston diameter–inertia load, and inertia load–radius factors and interactions.

Metin ZEYVELİa, *, Halil DEMİRa ve Hasan Basri ULAŞb, Abdulkadir GÜLLÜb a, * Karabük Üniversitesi... more Metin ZEYVELİa, *, Halil DEMİRa ve Hasan Basri ULAŞb, Abdulkadir GÜLLÜb a, * Karabük Üniversitesi, Teknik Eğitim Fakültesi, Makine Eğitimi Bölümü, 78050, Karabük, hdemir@karabuk.edu.tr , mzeyveli@karabuk.edu.tr b Gazi Üniversitesi, Teknik Eğitim ...

Strojniski Vestnik Journal of Mechanical Engineering, Aug 15, 2010

This study was carried out to investigate the effects of grain size on workpiece surface roughnes... more This study was carried out to investigate the effects of grain size on workpiece surface roughness and grinding forces when surface grinding AISI 1050 steel. A previously designed and constructed dynamometer was used to measure and record the forces developed during grinding. Grinding tests were carried out using different grinding wheels of different grains. Ground surface roughness measurements were also carried out. The results showed that grain size significantly affected the grinding forces and surface roughness values. Increasing grain size and depth of cut increased the grinding forces and surface roughness values. For different grain sizes, depth of cuts of 0.01 and 0.02 mm did not result in any significant variations in the grinding forces but further increase in depth of cut led to variations of up to 50% in grinding forces.

Materials & Design, 2006

In this study, AISI 304 stainless steel and St 52 carbon steel have been cut by plasma arc and th... more In this study, AISI 304 stainless steel and St 52 carbon steel have been cut by plasma arc and the variations of structural specifications occurred after cutting has been investigated. According to the experimental results, it has been seen that burning of particulars and distribution amount were increased when the cutting was performed using the speeds which are upper or lower limits of the ideal cutting speeds proposed by the manufacturer of the machine tool. Moreover, it was determined that the hardness from the outer surface to the core decreased, while the hardness near to the outer surface which affected by the high temperature occurred during cutting increased.

Politeknik Dergisi, 2007

ÖZET CNC işleme merkezlerindeki eğrisel hareketler dairesel interpolasyon hareketleri ile gerçekl... more ÖZET CNC işleme merkezlerindeki eğrisel hareketler dairesel interpolasyon hareketleri ile gerçekleştirilmektedir. Bu hareketlerdeki hatalar dairesellik hatası olarak adlandırılmaktadır. Bu çalışmada, dairesellik hatası ölçüm sistemi tanıtılmıştır. Dairesellik hatası tarif edilerek, bu hatanın değerlendirildiği algoritmalar tanıtılmıştır. Ayrıca bu sistemdeki ölçüm cihazları, ayrıntılı yayın taraması ile analiz edilerek tartışılmıştır.

Solid State Phenomena, Jun 5, 2013

ABSTRACT

Politeknik Dergisi, 2008

Bu çalışmada, AISI 316 paslanmaz çeliğin takma uçlu parmak freze ile işlenirken, kullanılan kesic... more Bu çalışmada, AISI 316 paslanmaz çeliğin takma uçlu parmak freze ile işlenirken, kullanılan kesici uç üzerindeki talaş kırıcı formun kesici kenar üzerindeki aşınmaya ve yüzey pürüzlülüğüne etkisi incelenmiştir. Bunun için kesme derinliği sabit tutularak, üç değişik talaş kırıcı formlu takım ve üç farklı kesme hızı (180, 225, 270 m/min) kullanılmıştır. Yapılan deneysel çalışmada, kullanılan kesici takımlardan ERGC kodlu takımın diğer takımlardan daha iyi aşınma ve yüzey pürüzlülüğü sonuçları verdiği ortaya çıkmıştır.

Solid State Phenomena, 2009

Statistic based predictive modelling is often used for structures which are especially difficult ... more Statistic based predictive modelling is often used for structures which are especially difficult to control and model. The modelling of hydraulic systems is challenging as they lose their stability due to the nonlinear parameters such as temperature changes, compressibility, leakages, load and friction. In the study, circularity error of curvilinear motions driven by this system is statistically analysed at the

zet Bu çalışmanın amacı, destekleyici yürüme cihazında bulunan kalça parçasının tasarımı ve anali... more zet Bu çalışmanın amacı, destekleyici yürüme cihazında bulunan kalça parçasının tasarımı ve analizidir. Bu mekanizma tam ya da kısmi yürüme engelliler için çok faydalıdır. Ayrıca kalça parçasın gerçek ortamda uygulanan yükler altında ne türlü tepki göstereceği sanal bir ortamda simüle ve analiz edilmiştir. Analizler için SolidWorks benzetim programı, en pratik çözümlerden biri olarak kullanılmıştır. Kalça parçasının Gerilim, deformasyon, yer değiştirme ve emniyet faktörü gibi analizleri gerçekleşmiştir. Buna ek olarak çeşitli bilgiler bu yöntemle hesaplanmaktadır. Bu yöntemde kalça parçasının imalatı uygun bir durumda yapılmıştır. Böylece hem zaman hem de malzeme israfı önlenmiştir. GİRİŞ Parçaların gerçek ortamda nasıl bir yük altında olacakları ve ne türlü tepki gösterecekleri SolidWorks 'un simülasyonu yazılım paketinde analiz yapılarak incelenmiştir. Yapılan mühendislik hatalarından doğan zararları ve zaman israfını önlemek ve güvenilir bilgiye erişmek için bilgisayar destek...

European journal of dentistry, 2008

The aim of this study was to investigate the effects of fiber-reinforced resin burs on the surfac... more The aim of this study was to investigate the effects of fiber-reinforced resin burs on the surface roughness of a nanofilled composite. Average surface roughness values (Ra, mum) were measured using a surface profilometer and surface textures after finishing procedures were evaluated using a scanning electron microscope (SEM). Thirty cylindrical specimens were prepared using sectional teflon molds. A nanofilled composite was chosen. After the preparation specimens were divided into three subgroups randomly. After profilometric measurements, representative samples of the mentioned finishing procedures were selected and SEM analyses were carried out. Mylar strip group was statistically different from the other two groups (P<.05). The smoothest surfaces occurred when composite resin samples were light cured against the strips. On the other hand there was no statistical difference between fiber-reinforced resin burs and Sof-Lex discs (P>.05). For fiber-reinforced resin burs scratc...

European journal of dentistry, 2012

The aim of this study was to evaluate surface roughness and hardness of a nanofiller GIC, a resin... more The aim of this study was to evaluate surface roughness and hardness of a nanofiller GIC, a resin-modified GIC, three conventional GICs, and a silver-reinforced GIC. For each material, 11 spcecimens were prepared and then stored in distilled water at 37 °C for 24 h. The surface roughness of 5 specimens was measured using a surface profilometer before polishing and after polishing with coarse, medium, fine, superfine aluminum oxide abrasive Sof-Lex discs respectively. The hardness of the upper surfaces of the remaining 6 specimens was measured with a Vickers microhardness measuring instrument. All tested GICs showed lower surface roughness values after the polishing procedure. Surface finish of nanofiller GIC was smoother than the other tested GICs after polishing. This was followed by resin-modified GIC, Fuji II LC; then silver-reinforced GIC, Argion Molar, conventional GICs, Aqua Ionofil Plus, Fuji IX, and Ionofil Molar, respectively. The result of the hardness test indicated that ...

Materials & Design, 2006

In this experimental study some statistical calculations have been made to eliminate quality prob... more In this experimental study some statistical calculations have been made to eliminate quality problems such as undesirable tolerance limits and out of circularity of spherodial cast iron parts during machining. X-R control charts have been constructed on the data obtained from this manufacturing to discover and correct assignable causes, so that the machine capability (Cp) and the process capability (Cpk) can be determined.

Materials & Design, 2006

In this experimental work, the influence of silane coated glass fibres added to polypropylene (PP... more In this experimental work, the influence of silane coated glass fibres added to polypropylene (PP) and polyamide 6 (PA6) plastics was investigated. These plastics were reinforced with (15 and 30 wt%) silane coated glass fibres. For this purpose, a die was designed and manufactured to produce tension and notched impact species using various injection parameters. Based on the results of this work, which investigates the influence of fibre reinforcement and injection parameters on the tensile strength and impact strength, PP and PA6 plastics reinforced with glass fibre exhibited improvement in their mechanical strength with the fibre reinforcement. However, improvement in the mechanical strength did not show a linear relationship with the fibre weight fraction on account of inhomogeneous fibre distribution and fibre fracture. In addition, tensile strength increased with increasing injection feeding zone temperature and decreased with increasing injection speed and extruder screw speed.

Sadhana, 2012

ABSTRACT In this study, a twin-axis gantry has been structured to examine hydraulic driven positi... more ABSTRACT In this study, a twin-axis gantry has been structured to examine hydraulic driven positioning skills of the curvilinear motions based on ISO 230-4 standard entitled ‘Circular tests for numerically controlled machine tools’. The system is controlled by a path and position control module of a PLC device. As a result of the experiments conducted based on the full factorial design, the effects of piston diameter, feed rate, radius and their two-way interactions on the circularity error are determined through analysis of variance. Accordingly, minimum circularity error is obtained with the piston diameter of 63 mm, inertia load of 12.5 kg, radius of 5 mm and feed rate of 50 mm/min as 0.345 mm. Circularity error increases with the increase of inertia load, radius and feed rate, and declines with the increase of piston diameter. Lastly, piston diameter has the greatest effect on the circularity error change and followed by radius, feed rate, piston diameter–radius, radius–feed rate, piston diameter-feed-rate, inertia load, piston diameter–inertia load, and inertia load–radius factors and interactions.

Metin ZEYVELİa, *, Halil DEMİRa ve Hasan Basri ULAŞb, Abdulkadir GÜLLÜb a, * Karabük Üniversitesi... more Metin ZEYVELİa, *, Halil DEMİRa ve Hasan Basri ULAŞb, Abdulkadir GÜLLÜb a, * Karabük Üniversitesi, Teknik Eğitim Fakültesi, Makine Eğitimi Bölümü, 78050, Karabük, hdemir@karabuk.edu.tr , mzeyveli@karabuk.edu.tr b Gazi Üniversitesi, Teknik Eğitim ...

Strojniski Vestnik Journal of Mechanical Engineering, Aug 15, 2010

This study was carried out to investigate the effects of grain size on workpiece surface roughnes... more This study was carried out to investigate the effects of grain size on workpiece surface roughness and grinding forces when surface grinding AISI 1050 steel. A previously designed and constructed dynamometer was used to measure and record the forces developed during grinding. Grinding tests were carried out using different grinding wheels of different grains. Ground surface roughness measurements were also carried out. The results showed that grain size significantly affected the grinding forces and surface roughness values. Increasing grain size and depth of cut increased the grinding forces and surface roughness values. For different grain sizes, depth of cuts of 0.01 and 0.02 mm did not result in any significant variations in the grinding forces but further increase in depth of cut led to variations of up to 50% in grinding forces.