Advanced SearchSearch Tips
Development of Small-Specimen Creep Tester for Life Assessment of High Temperature Components of Power Plant
facebook(new window)  Pirnt(new window) E-mail(new window) Excel Download
 Title & Authors
Development of Small-Specimen Creep Tester for Life Assessment of High Temperature Components of Power Plant
Kim, Hyo-Jin; Jeong, Yong-Geun; Park, Jong-Jin;
  PDF(new window)
The most effective means of evaluating remaining life is through the creep testing of samples removed from the component. But sampling of large specimen from in-service component is actually impossible. So, sampling device and small-specimen creep tester have been applied. Sampling device has been devised to extract mechanically small samples by hemispherical, diamond -coated cutter from the surface of turbine rotor bores and thick-walled pipes without subsequent weld repairs requiring post weld heat treatment. A method of manufacturing small creep specimen, 2min gage diameter and 10min gage length, using electron beam welding to attach grip section, has been proven. Small-specimen creep tester has been designed to control atmosphere to prevent stress increment by oxidation during experiment. To determine whether the small specimens successfully reproduce the behavior of large specimens, creep rupture tests for small and large specimens have been performed at identical conditions. Creep rupture times based on small specimens have closely agreed within 5% error compared with that of large specimen. The errors in rupture time have decreased at longer test period. This comparison validates the procedure for fabricating and testing on small specimen. This technique offers potential as an efficient method for remaining life assessment by direct sampling from in -service high temperature components.
Sampling Device;Small-Specimen Creep Tester;Electron Beam Welding;Creep Rupture Time;
 Cited by
Sp-Creep 시험에 의한 고온 크리프 특성 평가 기술 개발(ll) - 보일러 헤더 -,백승세;이동환;하정수;유효선;

대한기계학회논문집A, 2002. vol.26. 1, pp.55-60 crossref(new window)
Dooley, R. B., 1990, 'Condition Assessment Guidelines for Fossil Fuel Power Plant Component,' EPRI GS-6724, pp. 2-14

Melton, K. N., 1983, 'The Isostress Extrapolation of Creep Rupture Data,' Material Science and Engineering, Vol. 59, pp. 143-149 crossref(new window)

Wickens, A., John, H. M., 1977, 'Some Long Term Evidence Supporting the Constant Stress , Accelerated Temperature Method of Extrapolating Creep-rupture Data,' Arch. Eisenhuttenwes., Vol. 48, No. 11, pp. 591-593

U.S. Partent No.4845496, 'Surface Sampling Device'

Viswanathan, R., 1988, 'Remaining Life Estimation of Boiler Pressure Parts Volume 2: Miniature Specimen Creep Testing,' EPRI CS-5588, pp. 31-32

Richards, E. G., 1968, 'Influence of Specimen Size and Grain Size on the Creep Rupture Strength of Some Nickel-Base Superalloys,' J.Inst.Metal, Vol. 96, p. 365

Oxx, G. D., 1973, 'High Temperature Materials Selection and Acceptance,' Conference on Creep and Fracture in Elevated Temperature Application, Sheffield, pp. 50-58

박종진, 정용근, 주철홍, 1999, 'X20-CrMoV12 1강용접 열영향부의 크리프 손상 및 재질특성 평가,' 대한용접학회 제 1 회 강도분과연구위원회 학술세미나집, pp. 114-125