PRESSURIZED WATER REACTOR (PWR) PROJECT TECHNICAL PROGRESS REPORT FOR THE PERIOD AUGUST 24, 1962 TO OCTOBER 23, 1962

Technical Report · Thu Oct 31 04:00:00 EST 1963

OSTI ID:4729166

: 8 7 < = > ; : 6 = ; = = 8 poison elements was completed. The production yield through all Bettis operations is 95.8% for blanket elements, 95.9% for seed fuel elements, and 85% for poison elements. There are no major problems in blanket and seed fuel element post-bonding operations at WAFD, and 111 blanket subassemblies were welded to date. The manufacture of the boronated stainless steel poison wafers for PWR Core 2 Seed 1 was completed. The over-all final core B loading of the manufactured poison wafers released for poison element assembly was --0.43% from nominal. The most recent evaluations of the PWR Core 2 thermal performance disclosed a blanket capability significantly in excess of that of the seed, permitting a shift in flow from the blanket to the seed which improved over-all core capability. Core 2 capability was evaluated for core concentrations of Xe other than equilibrium Xe. Improvements in welding equipment have reduced the incidents of defective subassemblies requiring repair. An unacceptable amount of hot tears has been found in one side of one of the four WAFD development subassemblies intended to resolve the poison-clad melting problem. The fabrication of a replacement cluster for PWR Core 1 Seed 4 is essentially complete. The blanket fuel assembly and the reactor general assembly drawings were revised so as to indicate the classification of blanket fuel elements into Type I and Type II categories and to define acceptable core locations for each category. Representative thermocouple terminal box and flux thimble support bracket mock-ups were procured and installed on the full-scale head area mock-up. An evaluation was made of the thermal capability of PWR Core 2 Seed 2 at the beginning of life, which shows that this seed is capable of meeting its design power objective. The Seed 2 burnable poison was located in the subassembly end plates, thereby simplifying fabrication. The contemplated Reactor Protection System set points for PWR Core 1 Seed 4 were established. The set points cover the operation of Seed 4 from initial startup to Group IV rods at 72 in. at conditions of 100% power and equilibrium Xe. A review of the design transients and stresses imposed on the pressurizer surge line nozzle has indicated that the welds of the surge nozzle thermal liner are overstressed. It was recommended that a new thermal liner be installed and that the existing thermal liner be reanchored to the surge line piping in order to eliminate the possibility of this thermal liner moving into the pressurizer should the welds fail. Based upon observations of no increase in Hf/sup 181/ activity levels on components or increase in elemental Hf concentration in circulating crud during Seed 2 life, it is concluded that buildup of Ta by nuclear transformation in the Hf control rods over two seed lives has not presented a Hf corrosion problem. BEWI piping removed from PWR during Seed 2-3 refueling was not effectively decontaminated by the APAC process. This behavior is being investigated further. PWR-1 Seed 3 reached the end of full power equilibrium Xe lifetime after 6935 EFPH of operation. Preparations are in progress to extend core operation at reduced powers. The threedimensional depletion studies were extended through Seed 3 lifetime using actual control rod positions. Eigenvalues behavior is similar to that observed in the Seed 2 calculations and power sharing calculations were compared with measurements over the first half of Seed 3 life. For the irradiated fuel reactivity experiments, the reactivity perturbation introduced by local heating in an electrical heater of sample geometry (which simulates the BETA heating of an irradiated fuel sample) is found to behave like a change in thermal weighing functions plus a change in water-volume displacement. A first estimate of Core 2 Seed 2 loading requirement of 470 kg U/sup 235/ was obtained on the basis of a two-dimensional core depletion. This estimate is preliminary and wtll be used in detail design studies of the self

• Research Organization: Westinghouse Electric Corp. Bettis Atomic Power Lab., Pittsburgh
• DOE Contract Number: AT(11-1)-GEN-14
• NSA Number: NSA-17-007614
• OSTI ID: 4729166
• Report Number(s): WAPD-MRP-100
• Country of Publication: United States
• Language: English

Related Subjects

ABSORPTION
BLANKETS
BONDING
BORON
BURNOUT
BURNUP
CANNING
CONFIGURATION
CONTAMINATION
CONTROL
CONTROL ELEMENTS
CONTROL SYSTEMS
COOLANT LOOPS
CORROSION PROTECTION
CRITICALITY
CROSS SECTIONS
CURRENTS
DECONTAMINATION
DEFECTS
DENSITY
DISTRIBUTION
EFFICIENCY
EIGENVALUES
ELECTRONIC EQUIPMENT
ELEMENTS
FABRICATION
FAILURES
FERTILE MATERIALS
FISSIONABLE MATERIALS
FLUID FLOW
FUEL ELEMENTS
HAFNIUM
HAFNIUM 181
HEAT TRANSFER
HEATING
HIGH TEMPERATURE
IMPURITIES
IRRADIATION
MACHINE PARTS
MASS
MATERIALS TESTING
MATHEMATICS
MEASURED VALUES
MECHANICAL STRUCTURES
MELTING
MEMBRANES
MOCKUP
MONITORING
NEUTRON FLUX
NO
REACTOR TECHNOLOGY