skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Temperature actuated shutdown assembly for a nuclear reactor

Abstract

Three identical bimetallic disks, each shaped as a spherical cap with its convex side composed of a layer of metal such as molybdenum and its concave side composed of a metal of a relatively higher coefficient of thermal expansion such as stainless steel, are retained within flanges attached to three sides of an inner hexagonal tube containing a neutron absorber to be inserted into a nuclear reactor core. Each disk holds a metal ball against its normally convex side so that the ball projects partially through a hole in the tube located concentrically with the center of each disk; at a predetermined temperature an imbalance of thermally induced stresses in at least one of the disks will cause its convex side to become concave and its concave side to become convex, thus pulling the ball from the hole in which it is located. The absorber has a conical bottom supported by the three balls and is small enough in relation to the internal dimensions of the tube to allow it to slip toward the removed ball or balls, thus clearing the unremoved balls or ball so that it will fall into the reactor core.

Inventors:
 [1]
  1. Lisle, IL
Publication Date:
Research Org.:
Argonne National Laboratory (ANL), Argonne, IL (United States)
OSTI Identifier:
862619
Patent Number(s):
US 3976543
Assignee:
United States of America as represented by United States Energy (Washington, DC)
DOE Contract Number:  
W-31109-ENG-38
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
temperature; actuated; shutdown; assembly; nuclear; reactor; identical; bimetallic; disks; shaped; spherical; cap; convex; composed; layer; metal; molybdenum; concave; relatively; coefficient; thermal; expansion; stainless; steel; retained; flanges; attached; inner; hexagonal; tube; containing; neutron; absorber; inserted; core; disk; holds; ball; normally; projects; partially; located; concentrically; center; predetermined; imbalance; thermally; induced; stresses; pulling; conical; bottom; supported; balls; relation; internal; dimensions; allow; slip; removed; clearing; unremoved; fall; tube containing; thermally induced; neutron absorber; thermal expansion; nuclear reactor; stainless steel; reactor core; predetermined temperature; shutdown assembly; temperature actuated; metallic disk; actuated shutdown; bottom supported; located concentrically; /376/976/

Citation Formats

Sowa, Edmund S. Temperature actuated shutdown assembly for a nuclear reactor. United States: N. p., 1976. Web.
Sowa, Edmund S. Temperature actuated shutdown assembly for a nuclear reactor. United States.
Sowa, Edmund S. 1976. "Temperature actuated shutdown assembly for a nuclear reactor". United States. https://www.osti.gov/servlets/purl/862619.
@article{osti_862619,
title = {Temperature actuated shutdown assembly for a nuclear reactor},
author = {Sowa, Edmund S},
abstractNote = {Three identical bimetallic disks, each shaped as a spherical cap with its convex side composed of a layer of metal such as molybdenum and its concave side composed of a metal of a relatively higher coefficient of thermal expansion such as stainless steel, are retained within flanges attached to three sides of an inner hexagonal tube containing a neutron absorber to be inserted into a nuclear reactor core. Each disk holds a metal ball against its normally convex side so that the ball projects partially through a hole in the tube located concentrically with the center of each disk; at a predetermined temperature an imbalance of thermally induced stresses in at least one of the disks will cause its convex side to become concave and its concave side to become convex, thus pulling the ball from the hole in which it is located. The absorber has a conical bottom supported by the three balls and is small enough in relation to the internal dimensions of the tube to allow it to slip toward the removed ball or balls, thus clearing the unremoved balls or ball so that it will fall into the reactor core.},
doi = {},
url = {https://www.osti.gov/biblio/862619}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 1976},
month = {Thu Jan 01 00:00:00 EST 1976}
}