Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Shinohara, Masanori; Motegi, Toshihiro; Saito, Kenji; Haga, Hiroyuki; Sasaki, Shinji; Katsuyama, Kozo; Takada, Kiyoshi*; Higashimura, Keisuke*; Fujii, Junichi*; Ukai, Takayuki*; et al.
JAEA-Technology 2012-032, 29 Pages, 2012/11
JAEA-Technology-2012-032.pdf:6.57MB
An event, in which one of WRMs were disabled to detect the neutron flux in the reactor core, occurred during the period of reactor shut down of HTTR in March, 2010. The actual life time of WRM was unexpectedly shorter than the past developed life time. Investigation of the cause of the outage of WRM toward the recovery of the life time up to the past developed life is one of the issues to develop the technology basis of HTGR. Then, two experimental investigations were carried out to reveal the cause of the malfunction by specifying the damaged part causing the event in the WRM. One is an experiment using a mock-up sample test which strength degradation on assembly accuracy and heat cycle to specify the damaged part in the WRM. The other is a destructive test in FMF to specify the damaged part in the WRM. This report summarized the results of the destructive test and the experimental investigation using the mock-up to reveal the cause of malfunction of WRM.
Shinohara, Masanori; Motegi, Toshihiro; Saito, Kenji; Takada, Shoji; Ishimi, Akihiro; Katsuyama, Kozo
JAEA-Technology 2012-026, 21 Pages, 2012/08
JAEA-Technology-2012-026.pdf:2.31MB
An event, in which one of WRMs were disabled to detect the neutron flux in the reactor core, occurred during the period of reactor shut down of HTTR in March, 2010. The actual life time of WRM was unexpectedly shorter than the past developed life time. Investigation of the cause of the outage of WRM toward the recovery of the life time up to the past developed life is one of the issues to develop the technology basis of HTGR. Then, two experimental investigations were carried out to reveal the cause of the outage by specifying the damaged part causing the event in the WRM. The one is a post irradiation examination using the X-ray computed tomography scanner in Fuels Monitoring Facility (FMF) to specify the damaged part in the WRM. The other is an experiment using a mock-up simulating the WRM fabricated by the fabricator. This report summarized the results of the PIE and the experimental investigation using the mock-up to reveal the cause of outage of WRM.
Shinohara, Masanori; Sawahata, Hiroaki; Kawamoto, Taiki; Motegi, Toshihiro; Saito, Kenji; Takada, Shoji; Yoshida, Naoaki; Isozaki, Ryosuke; Katsuyama, Kozo
JAEA-Technology 2012-025, 31 Pages, 2012/08
JAEA-Technology-2012-025.pdf:4.69MB
An event, in which one of WRMs were disabled to detect the neutron flux in the reactor core, occurred during the period of reactor shut down of HTTR in March, 2010. The actual life time of WRM was unexpectedly shorter than the past developed life time. Investigation of the cause of the outage of WRM toward the recovery of the life time up to the developed life is one of the issues to develop the technology basis of High Temperature Gas cooled Reactor (HTGR). Then, a post irradiation examination was planned to specify the damaged part causing the event in the WRM was also planned. For the investigation, the X-ray computed tomography scanner in Fuels Monitoring Facility (FMF). This report describes the preliminary investigation on the cause of outage of the WRM. The results of study for transportation method of the irradiated WRM from HTTR to FMF is also reported with the record to complete the transport operation.
Kondo, Makoto; Iigaki, Kazuhiko; Motegi, Toshihiro; Emori, Koichi
JAEA-Testing 2009-002, 50 Pages, 2009/08
JAEA-Testing-2009-002.pdf:2.44MB
High Temperature engineering Test Reactor (HTTR) is a test reactor that build on sand layer formed during quaternary era. In principle, nuclear power generation facilities need to be supported on rigid rock formed during tertiary era, and now it is investigated to construct nuclear power generation facilities on sand layer formed during quaternary era for expanding suitable location. For this reason, we installed seismic observation systems in HTTR. And we have performed seismic safety evacuation using measured seismic acceleration in ground and building. This report compiles specifications of seismic observation systems, contents of check for seismic observation systems, check result of seismic observation systems and maintenance of seismic observation systems in HTTR.
Saito, Kenji; Shimizu, Atsushi; Hirato, Yoji; Kondo, Makoto; Kawamata, Takanori; Nemoto, Masumi; Motegi, Toshihiro
JAEA-Technology 2009-015, 52 Pages, 2009/05
JAEA-Technology-2009-015.pdf:10.17MB
As In-core temperature monitoring system, Type N thermocouples arranged at hot plenum block measures the primary coolant temperature at each hot plenum block in order to monitor the condition of the reactor core during the reactor operation. Type N thermocouples should have a long lifetime with high reliability under the high temperature environment of about 1000
C, because they are used in HTTR reactor pressure vessel. This report shows that the characteristic change of Type N thermocouples was confirmed from operation and maintenance data of current HTTR.
Tochio, Daisuke; Watanabe, Shuji; Motegi, Toshihiro; Kawano, Shuichi; Kameyama, Yasuhiko; Sekita, Kenji; Kawasaki, Kozo
JAEA-Technology 2007-014, 62 Pages, 2007/03
JAEA-Technology-2007-014.pdf:9.74MB
The rise-to-power test of the High Temperature Engineering Test Reactor (HTTR) was begun in April 2000. The reactor thermal power of 30 MW, which is the maximum thermal power of the HTTR, and the reactor outlet coolant temperature of 850C in normal operation was achieved in middle of December 2001. After that reactor thermal power of 30 MW a reactor outlet coolant temperature of 950C was achieved in the final rise-to-power test at April 2004. After receiving the operation permit, the safety demonstration tests were conducted to demonstrate inherent safety features of the HTGRs. This paper summarizes the HTTR operating experiences for five years since rise-to-power test that were catalogued into three categories, (1) Operating experience pertaining to new gas cooled reactor design, (2) Operating experience for improvement of the performance, (3) Operating experience due to fail of system and components.
Motegi, Toshihiro; Iigaki, Kazuhiko; Saito, Kenji; Sawahata, Hiroaki; Hirato, Yoji; Kondo, Makoto; Shibutani, Hideki; Ogawa, Satoru; Shinozaki, Masayuki; Mizushima, Toshihiko; et al.
JAEA-Technology 2006-029, 67 Pages, 2006/06
JAEA-Technology-2006-029.pdf:3.07MB
The plant control performance of the IHX helium flow rate control system, the PPWC helium flow rate control system, the secondary helium flow rate control system, the inlet temperature control system, the reactor power control system and the outlet temperature control system of the HTTR are obtained through function tests and power-up tests. As the test results, the control systems show stable control response under transient condition. Both of inlet temperature control system and reactor power control system shows stable operation from 30% to 100%, respectively. This report describes the outline of control systems and test results.
Saito, Kenji; Nakagawa, Shigeaki; Hirato, Yoji; Kondo, Makoto; Sawahata, Hiroaki; Tsuchiyama, Masaru*; Ando, Toshio*; Motegi, Toshihiro; Mizushima, Toshihiko; Nakazawa, Toshio
JAERI-Tech 2004-042, 26 Pages, 2004/04
JAERI-Tech-2004-042.pdf:1.16MB
The reactor control system of HTTR is composed of the reactor power control system, the reactor inlet coolant temperature control system, the primary coolant flow rate control system and so on. The reactor control system of HTTR achieves reactor power 30MW, reactor outlet coolant temperature 850C, reactor inlet coolant temperature 395C under the condition that primary coolant flow rate is fixed. In the Rise-to-Power Test, the performance test of the reactor inlet coolant temperature control system was carried out in order to confirm the control capability of this control system. This report shows the test results of performance test. As a result, the control parameters, which can control the reactor inlet coolant temperature stably during the reactor operation, were successfully selected. And it was confirmed that the reactor inlet coolant temperature control system has the capability of controlling the reactor inlet coolant temperature stably against any disturbances on the basis of operational condition of HTTR.
Hirato, Yoji; Saito, Kenji; Kondo, Makoto; Sawahata, Hiroaki; Motegi, Toshihiro; Tsuchiyama, Masaru*; Ando, Toshio*; Mizushima, Toshihiko; Nakazawa, Toshio
JAERI-Tech 2004-037, 33 Pages, 2004/04
JAERI-Tech-2004-037.pdf:4.08MB
HTTR (High Temperature Engineering Test Reactor) was operated from May 6th, 2003 to June 18th, 2003 to obtain operation data in parallel loaded operation mode and in safety demonstration tests. Operated with the reactor power at 60% of the rated power on May 21st, HTTR was automatically scrammed by a signalof "Primary coolant flow rate of the Primary Pressurized Water Cooler (PPWC): Low". The cause of the shutdown was the primary gas circulator (A) automatically stopped. The primary coolant flow rate of the PPWC decresed and reached the scram set value due to the gas circulator stop. As a result of investigation, it became clear that the cause of the gas circulator stop was malfunction of an auxiliary relay which monitored electric power of a circuit breaker in power line of the gas circulator. The cause of malfunction was deterioration of the relay under high temperature condition because the relay was installed beside an electric part which was heated up by electricity.
Shinohara, Masanori; Saito, Kenji; Motegi, Toshihiro; Takada, Shoji; Katsuyama, Kozo
no journal, ,
no abstracts in English
Saikusa, Akio; Inoi, Hiroyuki; Nojiri, Naoki; Shimizu, Atsushi; Mizuta, Naoki; Motegi, Toshihiro; Furusawa, Takayuki; Saito, Kenji; Shinozaki, Masayuki
no journal, ,
no abstracts in English