• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.1476-1479
• /
• 1996

The ring rolling process is one of the best known ring production method. The present model based control system was designed for rings with rectangle cross-section yet. An Adaptive Fuzzy Control for Closed-Die Ring-Rolling was developed in order to enhance the flexibility of the radial-axial ring rolling machine and to produce the rings with highly complex cross-section profile, roller bearing rings. A fuzzy method was implemented because of its simple application and to utilize the known process knowledge. The quality of the control system was estimated by die filling grad, which is strong dependent on the rising time of the controller. The rolling process parameters were also varied to determine their influence on filling of the ring profile. Die filling met the requirement of the industry.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1999.08a
• /
• pp.37-46
• /
• 1999

Sheet pil VL 제조에 있어서 핵심적인 중요 기술은 압연 중 진행 소재가 좌우 휨이 없이 직진토록하여 치입 상에 문제가 없어야 하는 것이며, 또 하나는 압연 완료후 냉각 중에 있는 제품의 bending량을 최소로 하여 roller 교정기에서 1차 교정으로 교정이 완료되게 하는 것이다. 압연중 소재가 직진토록 하기 위해서 web와 flange 등의 caliber 협상에서 balance가 유지되어야 하므로, web와 flange의 reduction을 1:1 vs 1.0으로 web의 압하가 flange에 비해 10%정도 크게 하였고, 좌우 flange의 reduction이 변화하지 않도록 flange 온도 보존을 위하여 intermediated에서 2 pass를 생략하여 약 40초의 rolling time을 단축시켰고, 이는 7$0^{\circ}C$정도의 온도 drop를 방지하는 효과를 나타내었다. 이로 인한 roll force는 약 15%정도 down 되었다. 논리상으로 A3 변태점 이하에서 web(두꺼운 부분 24.3mm)나 flange(얇은부분 9.5mm)가 동시에 압연이 완료된다면 bending량은 휠씬 줄어든 것이나, 이 경우 roll force 증가에 따른 roll 절손 사고의 위험과 설비 trouble이 우려되기 때문에 web 온도를 약 95$0^{\circ}C$에서 flange 온도를 83.$0^{\circ}C$에서 압연 완료토록 함으로써 설비 안전을 도모하였고, 1차 교정을 위하여 냉각 주수 설비를 설치하여 공냉시켰을 때의 1400mm에서 700mm로 bending량을 감소시킴으로써 이를 가능토록하였다.

• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.606-612
• /
• 2008

Creep force is one of the only appeared at conventional train which used to be driven by metallic wheel and rail contact. Due to the elastic deformation of wheel/rail contact patch by the weights of wheel and all the components related to it, creep force generates and becomes to the decision factor of critical speed of bogie(or railway vehicle) which is the criteria of avoiding vehicle to be unstable. There are many kind of factors which affect generation of creep force at a wheel/rail contact surface such as viscosity of contact patch, velocity, wheel and rail geometric profile, mechanical properties of wheel and rail. This paper concentrates on a wheelset simple 2 DOF Equation of Motion being exerted. From the simple numerical analysis using linear solution about getting creep force some factors could find roughly. Among the factors geometric parameter could be the one of most important for this study. In the future we'll prolong the range of study to find out method of measuring creep force easily.

• Journal of the Korean Society for Railway
• /
• v.10 no.5
• /
• pp.613-618
• /
• 2007

The performance of the railway bogie is classified into the stability and the steering performance. Testing for the bogie stability is conducted on the roller rig, but testing for the bogie steering performance on test facility is very difficult, so the testing for the vehicle curving performance is conducted on the real curve track. Testing the railway bogie on the full scale test rig is desirable, but it caused many problems relating to test costs and test time. As a possible alternative to overcome these problems, a small scaled test rig is actively used in the field of bogie stability. Thus, in this paper, we have studied a scaled track to test the bogie steering performance. For this purpose, we designed the 1/5 scaled test track equivalent to radius 200 curve and confirmed the validity of the testing for the bogie steering performance on the sealed curve track through the testing using 1/5 scaled bogie.