• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.7
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• pp.805-811
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• 2010

When we design a product, we spend a considerable amount of time in designing fasteners and their mating parts. Fasteners have special features because of which they are widely used and well standardized. Although we use some equations to design the fasteners, we should select these fasteners from the standardized table. In order to design them quickly using the CAD system, we proceeded as follows. First, we prepared some standardized shapes of fasteners to design them automatically. Next, we built a database of some fasteners such as a tension bolt, lock wire, thread, pin, and snap ring. Then, we used the design equations to quickly and precisely calculate the various parameters. Finally, we used a configuration design method to generate the shapes automatically using the results of the calculation and the values retrieved from the database. We applied this approach to the design of a propulsion structure, and demonstrated that this approach worked well and saved considerable time.

• Journal of Korean Association for Spatial Structures
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• v.6 no.3 s.21
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• pp.123-130
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• 2006

This study propose cutting body portion-high strength mechanical fasteners to improve deformation capacity of High strength bolts, which are the mechanical fasteners used for End-plate connections. And, we report that loading test results of steel beam-to-column connection using high deformation capacity-high strength bolts in accordance with SAC2000 loading program. As a result, the initial stiffness and the maximum strength of the connection using high deformation capacity-high strength bolts, are approximately the same in comparison with those of the end-plate connection using the existing high strength bolts. But the deformation capacity of the connection is more than twice as much as those.

• Journal of Surface Science and Engineering
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• v.51 no.5
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• pp.297-302
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• 2018

The important drawback of hardware fasteners consisted of 304 stainless steel (STS) is a frequent galling caused by a combination of friction and adhesion between the sliding surface. To improve the anti-galling effect, Sn-Al coatings by a thermal diffusion have been developed. The thermal diffusion by pack cementation with an $AlCl_3$ activator at $250^{\circ}C$ for 1 hour produced an Sn-Al alloy coating layer with an average thickness of $9.9{\pm}0.5{\mu}m$ on the surface of 304 STS fasteners. Compared with the galling frequency of the 304 STS fasteners, Sn-Al coatings on the surface of 304 STS fasteners demonstrated about 2.8-time reduction of the galling frequency.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.4
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• pp.11-19
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• 2022

In this study, in order to improve the splice performance of mechanical couplers, two new mechanical couplers with different connection modes were developed with rebar(SD400). The stress analysis of mechanical couplers with two different connection modes was carried out. Uniaxial tensile tests were carried out with type of steel, connection mode and the slope length of internal fastener as variables to analyze the influence on the maximum tensile strength. Building upon this previous work, the specimens that met the code in uniaxial tensile test were fabricated and static loading test and cyclic loading test were performed on the basis of Korean code(KS D 0249). The results of this research are as follows; (1) The tensile strength of steel and the slope length of internal fasteners have a certain influence on the maximum tensile strength. (2) The connection mode has some influence on the stiffness, slip and stiffness reduction rate of the connecting rebars. The results verify the feasibility of the proposed enhanced mechanical coupler in the field.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.5
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• pp.653-658
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• 2011

In general, the purpose of packaging fasteners is a series of management activities to maintain the condition at the time of production until they get delivered to the end user. An automatic packing system for fasteners is consisted of bucket conveyor, slide feeder, vision inspection system, box-magazine conveyor system and automatic packing machine. Also, the automatic packing machine is consisted of six modules including charging device, clamping/opening device, sealing/cutting device, feeding/air-shower device, supplying/adjusting device and device frame, etc. In this paper, we proposed an automatic packing mechanism of the one station concept for packing work of fastener objects where the continuous batch work is performed in a finite space. The proposed one-station packing mechanism has been optimized through mechanical, dynamical, structural and fluid analyses. And it had been manufactured as the prototype of automatic packing machine. The field test for validation of performance was performed directly at the production line of bolt and screw. In the field test, this packing machine showed an efficiency of about 4.5 times the manual operation. It also showed 30% reduction in the consumption of packing materials compared to the manual operation. This automatic packing machine for fastener objects will be commercialized soon.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.148-152
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• 2000

The aluminum alloy 6061-T6 has been successfully used in structural applications especially the pressure vessel of the Advanced Neutron Source research reactor. And aluminum alloys, including 6061-T6, have a face-centered-cubic crystals structure. Under normal circumstances face-centered-cubic crystal structures do not exhibit cleavage fractures even at very lo9w temperatures. In aluminum-based structures, plates frequently find use as connecting links. Mechanical fasteners are often utilized in instances where ease of application, familiarity with fabrication processes, and severe dynamic loading are of concern. Plates frequently find use as connecting elements in structures built from aluminum alloys. Many structural elements employ mechanical fasteners. Twenty and twenty aluminum alloy 6061-T6 plates, representing four different bolt patterns, were mechanically deformed. And variable materials such as A1 6061-T6, Al 2024-T3, Carbon/Epoxy, Glass/Epoxy Composite and Woven fiber composite, are used as patch materials. From this experiment, it has been shown that the strength of patch-repaired specimens is different with the patch materials.

• Steel and Composite Structures
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• v.33 no.3
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• pp.347-356
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• 2019

Most of the recent studies have improved the efficiency of FRP jackets for increasing the compressive strength, shear strength, and ductility of reinforced concrete columns; however, the influence of FRP jackets on the flexural capacity is slight. Although new methods such as NSM (near surface mounted) are utilized to solve this problem, yet practical difficulties, behavior dependency on adhesives, and brittle failure necessitate finding better methods. This paper presents the results of an experimental study on the application of fiber-reinforced polymer fastened mechanically to the concrete columns to improve the flexural capacity of RC columns. For this purpose, mechanical fasteners were used to achieve the composite behavior of FRP and concrete columns. The experimental program included five reinforced concrete columns retrofitted by different methods using FRP subjected to constant axial compression and lateral cyclic loading. The experimental results showed that the use of the new method proposed in this paper increased the flexural strength and lateral load capacity of the columns significantly, and good composite action of FRP and RC column was achieved. Moreover, the experimental results were compared with the results obtained from the analytical study based on strain compatibility, and good proximity was reached.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.9
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• pp.532-537
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• 2004

Shrink fitting is often a conventional mechanical fasteners and fastening methods with temperature difference. Localized heating of the material surface provides temporary expansion and allows slip fit assembly. The resulting interference fit exhibits exceptional strength without surface deformation at ambient temperatures. We studied an analysing method to find out a deformation of motor axis as variation of constrained method with shrink fitting.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1451-1453
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• 2003

Shrink fitting is often used to replace conventional mechanical fasteners and fastening methods. Localized heating of the mating surface provides temporary expansion and allows slip fit assembly. The resulting interference fit exhibits exceptional strength without surface deformation at ambient temperatures. We studied an analysing method to find out a deformation of motor axis with shrink fitting of thermal expansion.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.1
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• pp.83-88
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• 2015

At the early stages of engineering design, a number of design concepts may be suggested. With a great degree of freedom, making a good choice may be a challenge at this stage. In this study, a simplified evaluation criterion for design concepts is presented based on cost, simplicity and safety. Cost is estimated by the amount of materials and the required level of tolerance. Simplicity is represented by the number of parts, assembly steps, and fasteners. Safety is assessed by the level of potential failure. The proposed criterion is applied to an example design of driving mechanisms for cervical vertebrae massage machine.