Çelik halatlı titreşim sönümleyicilerin sonlu elemanlar metodu ile incelenmesi
Steel wire rope isolators analysis with the finite element method
Yazar: MEHMET KUDUZOĞLU
Danışman: DOÇ. DR. SERPİL KURT HABİBOĞLU
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Makine Mühendisliği Ana Bilim Dalı / Konstrüksiyon ve İmalat Bilim Dalı
Derece: Yüksek Lisans, 2018
Konu: Makine Mühendisliği = Mechanical Engineering
Dizin: Benzetim analizi = Simulation analysis ; Deformasyon analizi = Deformation analysis ; Dinamik analiz = Dynamic analysis ; Mekanik titreşim = Mechanical vibration

Özet:
Çelik halatlar günlük yaşamda ve endüstride çok geniş bir kullanım alanına sahiptir. En yaygın kullanım alanı bilindiği üzere transport sistemleridir. Asansörler, kren sistemleri ve diğer bir çok taşıma sistemi için çelik halatlar vazgeçilmez elemanlardır. Özellikle son dönemde çelik halatların farklı amaçlar ile de kullanılabileceği anlaşılmıştır ve bu konuda farklı çalışmalar devam etmektedir. Çelik halatların farklı kullanım alanlarından biri de titreşim sönümleyebilme konusundadır. Uygun tasarımlarla çelik halatlar titreşim sönümleyicilere dönüşebilmektedir. Endüstride de çelik halatlı titreşim sönümleyiciler giderek daha fazla rol almaya başlamıştır. Öyle ki basit bir makine sisteminden, son teknoloji savunma sistemlerine, havacılık sistemlerinde dahi kullanılmaya başlanmıştır. Fakat çelik halatlar karmaşık bir yapıya sahiptir. Bu açıdan çelik halatlı titreşim sönümleyicilerde kullanılan çelik halatların sonlu elemanlar yöntemi ile incelenerek, belirli koşullar altında da davranışlarına bakılmıştır. Normal transport sistemlerinde çelik halatlar genellikle çekme yüklerine maruz kalırlar. Ayrıca çelik halatların uygulamaları doğal olarak hep düz bir biçimde kullanılmalarına yöneliktir. Tüm asansör sistemlerinde, kren sistemlerinde çelik halatlar düz bir biçimde kullanılır. Sadece yön değiştirmesi gereken durumlarda büyük çaplı kasnaklar ile yön değiştirilmesi sağlanır. Fakat titreşim sönümleyici olarak kullanıldığında, çelik halatlar bir yay görevi görürler ve standart modelde bir yay gibi iki plaka arasına sarılırlar. Bu yay çeklindeki sarılım kullanıldığı sistem içinde değişmekle birlikte düzenli bir bası, çevrilme ya da kesme kuvvetlerine maruz bakır. Bu tip kuvvetler çelik halatların genel kullanım şeklinden farklıdır ve bu yüzden sonlu elemanlan yöntemi ile incelenmek istenmiştir. Yapılan çalışmada 3 farklı analiz kurgusu yapılmıştır. Birinci kurguda titreşim sönümleyci olarak modellenmiş sistemin, farklı kuvvetler altındaki davranışları incelenmiştir. Farklı kuvvetler için oluşan maksimum gerilmeler ve bu gerilmelerin hangi tel demeti üzerinde olduğu incelemiştir. Ayrıca yapılan analizler firma verileri ile karşılaştırılmıştır. İkinci tip analizde titreşim sönümleyicilerin imalatına yönelik bir analiz modeli oluşturulmuştur. İki plaka arasına sıkıştırılan çelik halatın en kadar sıkıştırılması gerektiği farklı analizler yapılarak karşılaştırma yapılmıştır. Üçüncü analiz tipinde yine çelik halatlı titreşim sönümleyicilerin imalatına yönelik bir çalışma olup, ise aynı koşullar ve çap değerleri için farklı halat tipleri analiz edilerek, halat tipleri arasında nasıl farklılıklar olabileceği gözlemlenmiş ve incelenmiştir.

Abstract:
Steel ropes are used in everyday life and the industry has a wide range of usage. The most common uses are transport systems. Steel ropes are indispensable elements for elevators, railway systems and many other transport systems. The first rope use dates back to 5000 BC. Steel ropes have always been used for similar jobs since this time period. Especially in the recent period it has been understood that steel ropes can be used for different purposes and different studies are continuing on this subject. The continuous structure of the steel ropes and the very dense structure allows for different usage areas. One of the different uses of steel ropes is vibration damping. The vibration damping concept occupies a large space in the industry. Vibration dampers are used in many places. With proper design, steel ropes can be transformed into vibration dampers. In these designs, steel ropes are constructed by wrapping like steel springs and have vibration damping and shock damping. Steel rope vibration dampers have also begun to play an increasing role in the industry. So much so that it began to be used in a simple machine system, state-of-the-art defense systems, even in aviation systems. Vibration dampers with steel rope can come in very large sizes. Very small sizes can be used in computer operating systems even in computer fans. Large-scale steel rope vibration absorbers can be used even on large ship machinery. There are also important uses in the aviation industry and the space industry. At the same time, steel ropes have a complex structure. Because steel ropes have a multi-piece structure. This very complex structure starts with 7 wires and can reach 60-70 wires. If we think that these wires are wrapped around each other, it is better to understand how complex the steel ropes are. In this respect, the steel ropes used in vibration dampers with steel rope are examined by the finite element method and their behaviors are examined under certain conditions. Because steel ropes are used under various conditions in vibration dampers with steel rope. In all systems such as elevator, train, steel ropes remain in the towing cargoes. In addition, the applications of steel ropes are always intended to be used in a flat form. In all elevator systems, steel ropes are used straight in the brake systems. In all elevator systems, steel ropes are used straight in the brake systems. In cases where it is necessary to change direction only, it is possible to change direction with large diameter pulleys. However, when used as a vibration damping device, the steel ropes act as a spring and are wrapped between two plates like a spring in the standard model. These two plates are generally produced in two parts and steel rope is compressed between these two parts. This spring-like sheath remains within the system in which it is used, but with regular pressure, turning or shear forces. This type of force is different from the general usage of steel ropes and therefore it is desired to investigate by the finite element method. The ABAQUS program was used for finite element analysis. One of the important points here is to assign a mesh. Due to the complex structure of the steel ropes it has become important to use the correct mesh structure. SOLIDWORKS commercial program is used for 3D modeling. Three different analysis designs were made in the study. In the first study, the behaviors of the system modeled as a steel rope vibration damper under different forces are investigated. First, force displacement analysis was performed for the selected model and compared with the experimental data generated by the firm for the selected model. Based on the experimental data, it is deemed appropriate to perform 5 different force-displacement analyzes. These 5 different analyzes contain 5 different force values. Initial analysis starting with 100N also ended with 500N force application. In the analyzes, the forces of 100N, 200N, 300N, 400N and 500N were applied to the maximum displacement and maximum stresses. The results of the analysis were then collected and compared with experimental data. A company data was used for the experimental data. The maximum dislocation value was measured as 1.6mm in the analysis where force is applied at the value of 100N, which is the first of the analyzes made. The maximum tensile strength is around 324 N / mm2, and it is found at the top of the steel rope. In the second analysis of the applied analyzes, the maximum displacement value was measured as 2.5mm in the force-applied analysis. The maximum tensile strength was around 515 N / mm2, and it reached the bottom of the steel rope. The maximum displace- ment value was measured as 3.6mm in the analysis with force of 300N, the third of the analyzes made. The maximum tensile strength is 718 N / mm2. This maximum tensile strength is seen in the middle of the steel rope and in the center wire. The maximum displacement value was measured as 4.6mm in the analysis of force applied at the fourth of the analyzed analyzes, 400N. The maximum tensile strength is 941 N / mm2. This maximum tensile strength is found at the bottom of the steel rope and at the center wire. The maximum displacement value was measured as 5.7 mm in the analysis of the force applied at the fourth order of the analysis, 500N. The maximum tensile strength is about 1147 N / mm2. This maximum tensile strength was again found at the bottom of the steel rope and at the center wire. Comparing these five different analyzes, it is seen that the maximum displacement increases proportionally with increasing force and stress values. Furthermore, when the maximum stresses were examined, it was observed that the maximum stresses increased with increasing forces. The maximum tension zones vary around the center line, though varying with increasing force. Another analysis is an analysis calculated for 1 second duration for 300N force application, in which the damping response of the selected steel rope vibration absorber is looked at. When the results are examined, it can be seen that the selected steel rope vibration damping model gives similar results to the vibration damping response of springs. The steel rope vibration damper followed a decreasing oscillation curve for 1 second. Higher oscillation values of up to 0.35 seconds were observed, whereas after 0.35 seconds the original rope vibration attenuator showed a severe damping response. Another analysis made is to see the limits of the steel rope vibration damper. Stresses and damage that occurred when the force of the selected steel rope vibration absorber was left to the pressure force was examined. As a result of the analysis, the maximum stresses were found to reach very high values and steel wire rope would be damaged by macro level. In such a repetitive force application, the life expectancy can be predicted to be low. It can also be said that the separation between the wires has increased significantly and has reached a level that is easily visible. The maximum tensile strength is again in the middle and center wire. Comparisons of company catalogs and analysis data were made and similar results were obtained. The company data and the analysis data of the selected steel rope vibration absorber coincide with each other. From here, the stress values that occur at the site or at the end of applied forces are examined. In addition, displacement graphs gave similar results to steel springs as expected. We have studied the maximum stresses that occur for different forces and which wire strands overlie these stresses. In addition, the analyzes made are compared with the data of the firm. In the second type of analysis, an analysis model for the manufacture of vibration dampers was developed. Comparisons were made by performing different analyzes in which the steel wire rope clamped between the two plates should be compressed as much as possible. As mentioned, the most classic model of steel rope vibration dampers is formed by clamping steel ropes between two plates. these two plates clamp steel ropes with bolts. The important issue here is how much the plates need to compress the steel ropes. In the production of the plates firstly the apartments are built tomorrow. Then the sawdust is removed from the surface of the circle tomorrow. Compression of steel rope is ensured as much as the amount of raised steel. In the analyzes carried out here, different analyzes were carried out for different amounts of chip removal. In the analyzes made, a similar mesh model was used with the other analyzes. At the same time, the step and load properties are the same. As in the other analyzes, the analysis was also done explicitly here. SOLIDWORK program is used for 3D modeling. There are 5 different analyzes in this section. Different plate sizes were used in each analysis. In the analyzes performed, different plate sizes and results were compared and evaluations were made on the most appropriate plate size for the selected rope diameter. For example, the model analyzed and analyzed is a steel wire rope with a diameter of 3.2mm. In order to compress this rope, a small hole of 3.2 mm must be made or the material should be taken from the surface of the plate where it is a semi-circular cavity. A half-circle groove with a diameter of 3.2 mm was formed in the half-plate and the finished surfaces were machined to X. The same procedure is applied to both half plates so that the steel rope is compressed between these grooves. This section will also examine the changes made on the wire rope for the same model over the X-value. The first analysis made is analysis for a compression value of 0.1 mm blank. It is observed here that the maximal stress is 81.86 N / mm2. The maximum tensile strength was found to be the middle part with 6 pieces of steel wire. A severe stress increase was observed after 0.25 seconds for a 0.3 second analysis. The second analysis made is analysis for a compression value of 0.15 mm blank. It is observed that the maximal stress is 318.4 N / mm2. The maximum tensile strength was found to be the middle part with 6 pieces of steel wire. A severe stress increase was observed after 0.17 seconds for a 0.3 second analysis. The third analysis made is analysis for a 0.2 mm blank compression value. It is observed here that the maximal stress is 652.6 N / mm2. The maximum tensile strength was found to be the middle part with 6 pieces of steel wire. A severe stress increase was observed after 0.2 seconds for a 0.3 second analysis. The fourth analysis made is analysis for a compression value of 0.25 mm blank. It was observed here that the maximum tension was 1167 N / mm2. The maximum tensile strength was found to be the middle part with 6 pieces of steel wire. A severe stress increase was observed after 0.21 seconds for a 0.3 second analysis. The final analysis made is analysis for a 0.3 mm blank compression value. It was observed here that the maximal tension was 1774 N / mm2. The maximum tensile strength was found to be the middle part with 6 pieces of steel wire. For 0.3 second analysis, a significant increase in tension was observed after 0. 0 second. Compared to the analyzes made, a significant increase in tensile strength was observed in the plate cavities of 0.2 mm denier. Also in all analyzes the maximum stress was found in the middle part. In addition, while the curve for the formation of maximum stress followed a similar path in the first two analyzes, this curve followed a different path for the last three analyzes. In the third type of analysis, it is also a study for manufacturing of steel rope vibration dampers, and it is observed and examined how differences between rope types can be analyzed by different rope types for the same conditions and diameter values. In this section, compression analysis is applied for 3 types of ropes. Based on the compression analyzes made in the previous section, it was decided to carry out the analysis with plates with a gap of 0.15 mm between plates. The rope types used are all 3.2mm in diameter, and 1x19, 1x37 and 7x7 type ropes are selected as type. The first analysis was made for the 1x19 type rope. The maximum tensile strength was observed at 318.4 N / mm2. The maximum stress zone was observed in the middle layer. The second analysis was made for the 1x37 type rope. The maximum tensile strength is 158 N / mm2. The maximum stress zone was observed in the middle layer. The third analysis was made for the 7x7 type rope. The maximum tensile strength was observed to be 168.2 N / mm2. The maximum stress zone was observed in the middle layer. The stresses to be generated for a compression of 0.15 mm were investigated in the analyzes made. The resulting strains are all in the safe zone. The wire breaking strength in steel ropes ranges from 1568 N / mm2 to 1800 N / mm2. The tension between the ropes reached 318.4 N / mm2 and 1x19 rope.