This study was conducted to evaluate the feasibility of applying a bending process as an alternative to the conventional welding method for rolled homogeneous armor(RHA) steel used in the turret structures of tanks. After analyzing the turret geometry and the mechanical characteristics of RHA steel, the upper and lower die profiles were optimized based on the MIL-DTL-12560 specification. Through forming simulations, the appropriate die opening width and punch stroke were derived. In particular, the final bending conditions were determined by accounting for springback effects. Structural analysis results confirmed that the maximum residual stress and total strain remained within the allowable mechanical limits of RHA steel, and the strain values approached the material’s elongation limit of approximately 15%, ensuring practical forming stability. This study presents a practical guideline for die design and bending conditions applicable to high-strength armor steels, and is expected to serve as a foundational reference for process optimization in the manufacturing of military vehicles and protective structures.
An automatic fire extinguishing system is installed inside the hull of the K2 main battle tank to protect equipment and crew members in the event of a fire and to enable continuous combat operations. This system detects heat sources and visible light to identify fires and discharges an extinguishing agent within milliseconds. However, there have been concerns that direct contact between the extinguishing agent(HALON 1301) and the driver-particularly on the arms or sides-could result in cold burn-like injuries. To mitigate this risk, the nozzle design of the fire extinguisher was modified to minimize crew exposure. Through modeling simulations and live fire suppression tests, it was verified that the redesigned nozzle still provides effective fire suppression. This study contributes to improving crew safety and enhancing the operational reliability of military equipment while reducing the risk of personnel injury and resource loss due to safety incidents.
The K2 tank not only has excellent mobility but also has excellent protection performance. Armor steel is used to provide structural protection, and the turret structure is made of rolled homogeneous armor (RHA) plates. Most processes for fabricating structures involve welding, but RHA steel has the problem of being susceptible to thermal deformation. To compensate for this, a plan to apply the bending method was considered. In this study, prior to applying the bending method to an actual vehicle, mechanical property evaluations were performed on materials, welding, and bending specimens. It has been proven that the bending method can achieve performance equivalent to or better than the welding method. The verification tests included hardness tests, tensile tests, fatigue tests, and impact tests. All tests except the impact test confirmed that the bending method was superior to the welding method. In the case of the impact test, the impact value of the bending method was lower, but it satisfied the standard with a value higher than the minimum requirement according to the standard, so it is judged that there will be no problem in applying the bending method.
In this study, we addressed the prevention of fire extinguishing device malfunction caused by noise in the fire detector of automatic fire extinguishing devices applied to mobile equipment such as armored vehicles and tanks. The automatic fire extinguishing system consists of a fire detection unit, an automatic control unit, and a fire suppression unit. In the case of a fire detector, it is a major component of the fire detection unit. Even though no fire occurred during operation in the field, a number of fire extinguisher sprays occurred, and the malfunction of the fire detector, which is a fire detection unit, was reproduced. The cause was identified as noise in the fire detector connector due to vibration and shock that may occur during operation of the mobility equipment. In order to solve this problem, noise generated momentarily from a fire detector is treated as an exception, and when a fire signal is transmitted from the fire detector to the automatic control unit for more than a certain period of time, Software has been improved to enable fire extinguishers to operate. This study analyzed the causes of malfunctions in automatic fire extinguishing devices, which are components of mobile equipment, and derived improvement measures to improve the reliability of automatic fire extinguishing devices.
Advanced technoloigy, according to the development of science, is also applied to weapons systems to prepare for future battles. But the emergence of new technologies leads to DMSMS(Diminishing Manufacturing Source and Material Shortage) because it brings a short life cycle of parts. In particular, DMSMS frequently appear in electronic parts with a short launch cycle for new products. The life support system of K2MBT(Main Battle Tank) is a key functional item related to crew survivability and convenience. Recently, various parts have been cut off on the life support system, requiring a redesign of the Control Box. The K2MBT is not only central to domestic production but also plays a key role in export projects to countries like Poland, making continuous production necessary. This study aimed to ensure the sustainability of component production and reduce maintenance costs by redesigning the control box.
In this article, improvement of heat screen failure for battle tank is proposed. The heat screen applied to protect a cam sensor from engine heat was cracked by vibrations generated in the engine. To solve this problem, the configuration of the heat screen was changed to a structure that can avoid engine vibration levels. The improved heat screen has first mode frequency at 4,000 RPM band outside the main operating range of the engine, and heat dissipation is at the same level as conventional heat screen. As a result, the improved heat screen secured reliability by improving vibration effects by approximately 163% while maintaining heat dissipation performance.
The main hydraulic pump is a device that generates the hydraulic pressure needed for the K2 tank. It is a pressure-compensated swash plate piston pump that generates the hydraulic power necessary to drive the hydraulic device. Hydraulic pump design changes were made due to frequent failures of the hydraulic pump. As a result of checking the operation records of the hydraulic pump, about 71% of the total engine operation time was in a stationary state where hydraulic pressure was not needed. This has the problem of constantly running when the engine is started, consuming unnecessary endurance time, and generating high noise. In this study, ISG(Idle Stop & Go) was applied to improve operation method. When applying ISG, the pressure can be reduced to about 85% or less in an environment where the operation of the main hydraulic pump is not necessary. So, the lifespan of the main hydraulic pump increases as a result of ISG application, thereby reducing the waste of national funds due to maintenance costs. Also, it is expected to contribute to improving combat power by reducing crew fatigue due to noise reduction.
In this study, the abnormal noise phenomenon generated intermittently in the shock absorber of the combat armored vehicle was approached from the side of the squeak joint to solve the phenomenon. In order to identify the cause of the noise, the factors causing friction in the shock absorber were checked from the viewpoint of problem product analysis, process, and design. As an improvement plan, by improving the non-lubricated section in the nitrogen chamber, the operating noise was reduced to a level lower than that of a general automobile engine along with the elimination of noise. Considering that this is a combat vehicle, it is judged that it has been improved so as not to affect the survivability and health of the crew during equipment operation. Through the improvement of this study, it is expected to prevent power loss and improve the emotional quality of our soldier.
본 연구는 아로마 롤온 흡입법이 경로당 이용 노인의 스트레스, 통증, 우울 및 혈압에 미치는 효과를 확인하기 위한 원시실험연구이다. 대상자는 경기도 S시에 위치한 경로당 2곳에 등록된 노인 가운데 선정기준에 부합한 33명이 참여하였으며 자료수집 기간은 2022년 11월 14일부터 2022년 12월 19일까지 시행하였다. 아로마 롤온 흡입 전후에 경로당에 직접 방문하여 혈압 측정 후 자가설문으로 구성된 스트레 스, 통증, 우울을 조사하였다. 실험군에게 적용한 에센셜 오일은 마조람, 제라늄, 페페민트, 오렌지 스위트 를 캐리어 오일인 호호바오일에 희석한 것으로 하였다. 중재는 4주 동안 1일 3회 시행하였다. 연구결과, 아 로마 롤온 흡입법은 대상자의 스트레스(t=2.63, p=.013), 통증(t=2.46, p=.019), 수축기 혈압(t=3.01, p=.005)에서 통계적으로 유의한 차이가 있었다. 따라서 아로마 롤온 흡입법은 경로당 이용 노인의 스트레 스 감소 및 통증 완화, 혈압 관리에 유용한 간호중재로 활용가능할 것으로 기대된다.