US 12,188,318 B2
Tool
Martin Derrick Innes, Aberdeen (GB); and Simon McKay, Banchory (GB)
Assigned to SPEX GROUP HOLDINGS LIMITED, Aberdeen (GB)
Appl. No. 17/776,532
Filed by SPEX GROUP HOLDINGS LIMITED, Aberdeen (GB)
PCT Filed Nov. 13, 2020, PCT No. PCT/EP2020/082134
§ 371(c)(1), (2) Date May 12, 2022,
PCT Pub. No. WO2021/094582, PCT Pub. Date May 20, 2021.
Claims priority of application No. 1916511.7 (GB), filed on Nov. 13, 2019.
Prior Publication US 2022/0381102 A1, Dec. 1, 2022
Int. Cl. E21B 29/02 (2006.01); E21B 43/116 (2006.01); E21B 43/263 (2006.01)
CPC E21B 29/02 (2013.01) [E21B 43/116 (2013.01); E21B 43/263 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A downhole perforator tool comprising a housing, the housing comprising:
an inner surface configured for mounting to a tubular carrier in use;
an outer surface;
two or more chambers provided between the inner surface and the outer surface and containing at least one propellant source;
an ignition system for igniting propellant at the at least one propellant source; and
one or more outlets leading from the chambers to the outer surface, for combustion products from the at least one propellant source;
wherein the housing comprises cylindrical sleeves including the two or more chambers, and one or more circumferential rings including the one or more outlets, to provide a generally cylindrical housing with a bore therethrough;
wherein a cavity within the cylindrical sleeves is divided into the two or more chambers by blocks of a thermosetting resin or other polymer;
wherein the outer surface of the cylindrical sleeve or sleeves is of metal and the inner surface is of a thermosetting resin or other polymer;
wherein each outlet comprises one of more apertures which act as nozzles for jets of combustion products from the at least one propellant source; and
whereby the jets of combustion products are configured to produce access holes into a rock formation.