• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.15 no.3
• /
• pp.72-78
• /
• 2016

In this study, we analyzed the accidental hydrogen embrittlement affecting the track nut on a self-propelled howitzer. Tracks are key components to maintain a high degree of confidence in the operation of the self-propelled howitzer and the safety of the crew. This study analyzed the fractured surface using SEM to review accidental damage of the wedge nut. In addition, we conducted revival tests and analyzed the results to identify the cause of the wedge nut damage from hydrogen embrittlement. We should carry out factor analysis and continuous improvement of the manufacturing process to determine the accidental breakage mechanism for future enhancement of the self-propelled howitzer. This study will be the useful reference for enhancing process designs in similar products.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.25 no.6
• /
• pp.553-560
• /
• 2022

This study investigates improvement of torsional strength of special wrench for K-series self-propelled howitzer power-pack maintenance. In order to maintain the power-pack, special wrench is one of the essential tools for assembling/disassemblimg the engine and transmission. However, failures(plastic deformation, fracture phenomenon and etc.) have been frequently reported even though special wrench was used within recommended standard torque range. Therefore, in this study, finite element analysis using ABAQUS was performed and modification of design parameters have been proposed. Prototypes based on the proposed parameters were manufactured and torsional experiment(torque about 130 % of recommend maximum torque) validated the newly proposed design parameters. Special wrench based on this study is applied to mass production and currently used for the maintenance.

• Journal of the military operations research society of Korea
• /
• v.31 no.2
• /
• pp.75-85
• /
• 2005

Even though K-series combat equipment's engine depot maintenance cycle of ROK army is 10years In average, that of the K-9 Self Propelled(SP) howitzer which has been fielded since 99 $3{\sim}4$years causing limitations to effective equipment operations and combat-readiness. Therefore, the current K-9 self-propelled howitzer engine operation period of 1,500 hours, which is greatly shorter than other equipments, had to be verified. In order to find the optimum depot maintenance cycle, related field operation conditions were verified and opinions were collected, and also the background on current depot maintenance cycle setting was studied.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.11
• /
• pp.139-147
• /
• 2016

This study described the design scheme for each step of the production test for the Fire Control System(FCS) of the K-55A1 PIP business of Hanwha Thales since 2011. From the time of receipt of the product It is necessary to improve the FCS's reliability by using the Unit Test, burn-In test, System Test. FCS of K-55A1 acts as a 'head' that control the self-propelled howitzer, and connected with the electrical and physical connection of self-propelled howitzer's multiple unit (Inertial navigation systems(IN), Muzzle Velocity Radar (MVR)) for the normal operation without an inch of error in operating. We designed the production testing equipment automatically as much as possible and designed with the environment similar to the self-propelled howitzer. by using this production testing equipment, It should help for the strengthen national defense of the Republic of Korea.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.12
• /
• pp.3767-3781
• /
• 1996

Generally, dynamic loads are applied to real structures. Since the analysis with the dynamic load is extremely difficult, static loads are utilized by proper conversions of the dynamic loads. The dynamic loads are usually converted ot static loads by safety foactors of experiences. However, it may increase weight and decrease reliability. In this study, a method is proposed for the conversion process. An equivalent static load is calculated ot generate a same maximum displacement. The method is verified through numerical tests on a spring-mass systems of one and multi degrees-of freedom. It has been found that the duration time of the loads and the natural frequencies of the structures are critical in the conversion process. A road arem is a self-propelled howizer is selected for the application of the proposed method. The shape of the road arm is optimized under the converted static loads.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.2 no.1
• /
• pp.61-72
• /
• 1999

A Technical Manual is the tool that offers a guidance to a maintenance engineer in order to exactly use and maintain of complicated weapon system. Because the modern weapon system are complex and functionality integrated, its quantity is massive. So We spend a lot of money on its publication and suspending recent information. To solve this problem, to reduce a risk of loss and use easily, this study develops the IETM(Interactive Electronic technical manual) which observes the CALS standard. This paper provide the development concept, environment, technic of IETM.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.14 no.4
• /
• pp.615-621
• /
• 2011

In this paper, the proper quantity of conditioning rounds has been studied using the statistical analysis on the basis of the acceptance test data of K676 and K677 propelling charge for K9 self propelled howitzer. In general, the muzzle velocity of the initial rounds tends to be a little lower than that of the succeeding rounds. The latter rounds are likely to have the constant velocities after firing the appropriate conditioning rounds. The main cause of velocity difference was proved to be the proper quantity of conditioning rounds by doing the correlation analysis among the initial tube temperature, the tube life and the quantity of conditioning rounds. The result of paired t-test shows that two rounds of conditioning projectiles are proved to be enough to maintain the constant velocity in the case of the acceptance test of K676 and K677 propelling charge.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.19 no.2
• /
• pp.171-176
• /
• 2016

In this paper, the integration of the firing test stages at the acceptance test of the propelling charge has been studied using statistical analysis on the basis of the test data of K676 and K677 propelling charge for K9 self propelled howitzer. Acceptance test of K676 / K677 propelling charge consists of 3 stages and each stage is charge assessment test, charge uniformity test and charge proving ground test. Many of rounds are fired and much money is spent to prove the charge performance at each stage. The result of t-test shows that there is no difference between charge uniformity and charge proving ground test stage of K676 and K677 propelling charge.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.5
• /
• pp.443-450
• /
• 2020

This paper reports a design improvement study to solve the stoppage phenomenon caused by the launch-support device applied to K105A1. The K105A1 is a weapon system equipped with an old 105 mm towed howitzer in a wheeled vehicle, which provides superior maneuverability compared to track equipment. The launch support device serves to withstand fire impact and load. In this way, this device is fixed firmly to the ground in preparation for the shooting mission and is responsible for the critical performance, such as fixing the position of the vehicle. On the other hand, during the field test, a temporary stoppage of the launch support occurred, which caused a problem of not being fixed to the ground. To solve this problem, the cause of failure was analyzed by a replay test and parts inspection. In addition, the operating concept, method, and design were analyzed to derive the cause and solve the problem by changing the parts design. Finally, the performance and firing missions were performed normally by applying the changed design to K105A1. The performance stability and reliability of the launch support device were confirmed, which are expected to be of great assistance in the development of military equipment in the future.