Development of measuring device for inner surfaces of embedded piping (Contract research)

Ito, Hirokuni*; Hatakeyama, Mutsuo*; Tachibana, Mitsuo; Yanagihara, Satoshi

JAERI-Tech 2003-012, 34 Pages, 2003/03

JAERI-Tech-2003-012.pdf:2.87MB

The MISE was developed to evaluate low-level radiological contaminations of inner surfaces of piping. The MISE consists of a cylindrically-formed double layered type detector and a piping crawling robot, which were designed and manufactured separately. In measurements of the contaminations, an outer cylindrical detector close to the surface of piping measures -rays and -rays and an inner cylindrical detector set after a shielding plate for shield of -rays measures -rays. The -ray counting rates are derived by subtracting -ray counts measured by the inner detector from - and -ray counts measured by the outer detector. The robot transports the double layered type detector with observing inner surfaces of piping. The detection limit for the contamination of Co was found to be about 0.17Bq/cm with measurement time of 30 seconds. It is expected that 0.2Bq/cm corresponding to clearance level of Co (0.4Bq/g) can be evaluated with measurement time of 2 seconds, which is equal to measurement speed of 54m/h.

Multiaxial creep behavior of nickel-base heat-resistant alloys Hastelloy XR and Ni-Cr-W superalloy at elevated temperatures

Tsuji, Hirokazu; Nishi, Hiroshi; Kaji, Yoshiyuki; Muto, Yasushi; Penkalla, H. J.*; Schubert, F.*

Proceedings of the 7th International Conference on Creep and Fatigue at Elevated Temperatures (CREEP7), p.101 - 106, 2001/06

A series of uniaxial and multiaxial creep tests was carried out on Hastelloy XR and Ni-Cr-W superalloy, which were developed as the high temperature structural materials for nuclear application at the JAERI, in order to investigate multiaxial creep behaviors of these materials. Norton's creep law and von Mises' flow rule were applied to the prediction of multiaxial creep behavior of a tube under some significant loading condition. In most cases the multiaxial creep behavior of these materials were successfully described with the constitutive equations based on the material parameter fitting uniaxial creep test results, though a few exceptional cases were observed. The present study has revealed that the method based on Norton's creep law and von Mises' flow rule are basically applicable for the description of the multiaxial creep behavior for Hastelloy XR and Ni-Cr-W superalloy as the conventional design method.