US 11,948,700 B2
In-situ method of drilling to collect dry samples from a nuclear reactor core interior for analysis
Grant Charters, Golden, CO (US); and Sudesh Aggarwal, Golden, CO (US)
Filed by Grant Charters, Golden, CO (US); and Sudesh Aggarwal, Golden, CO (US)
Filed on Nov. 11, 2020, as Appl. No. 17/094,850.
Prior Publication US 2022/0148746 A1, May 12, 2022
Int. Cl. G21C 19/20 (2006.01); G01N 1/08 (2006.01); G01T 7/02 (2006.01); G21D 1/00 (2006.01); G01N 33/20 (2019.01); G21C 17/06 (2006.01); G21C 19/02 (2006.01)
CPC G21C 19/20 (2013.01) [G01N 1/08 (2013.01); G01T 7/02 (2013.01); G21D 1/003 (2013.01); G01N 33/20 (2013.01); G21C 17/06 (2013.01); G21C 19/02 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method which includes collecting nuclear reactor core samples in-situ
from one or more layers of irradiated core material by
using a metal-cutting drill bit made of tungsten carbide,
the method comprising:
penetrating an outer concrete bioshield wall of the nuclear reactor using a masonry drill bit;
after penetrating the outer concrete bioshield wall, replacing the masonry drill bit with the metal-cutting drill bit, wherein the metal-cutting drill bit includes:
a hollow drill bit shaft body, having an interior airflow passage formed therein, sitting concentrically along a longitudinal axis of the metal-cutting drill bit;
a tungsten carbide sampling cutting head with
a plurality of cutting arms extending radially outward with equally spaced chip grooves along a cutting face of the tungsten carbide sampling cutting head
and a plurality of air holes formed through a flank face of the tungsten carbide sampling cutting head, in communication with the airflow passage,
wherein the plurality of cutting arms are spaced apart radially about a central axis of the tungsten carbide sampling cutting head; and
at least one particulate air guide behind the plurality of cutting arms operable to guide air and particulate forward to behind the tungsten carbide sampling cutting head;
taking an incremental sample at a predetermined increment by rotationally cutting into a metal alloy object or metal component of the core to produce one or more of metal chips, filings, and dust; and
collecting the one or more of metal chips, filings, and dust within a filter
which is located within a hermetically sealed containment glove box in hermetic communication with the airflow passage,
wherein said collecting is performed by creating a vacuumed airflow through the airflow passage and at the tungsten carbide sampling cutting head
causing the one or more of metal chips, filings, and dust to be pulled through the plurality of air holes and into the airflow passage and ultimately into the filter.