Abstract A method for carrying out underwater demolition work with a hollow charge constituted as a hollow body with a front, a back, an outer shell of frusto-conical shape and an inner shell of conical shape. The shells diverge toward the front of the body with the ends of said shells being joined at the front to define a space between the shells containing an explosive charge. A cover is mounted on the back of the body, and a base is mounted on the front of the body. The hollow charge is placed underwater on the submerged surface to be blasted and the explosive charge in the hollow body is detonated to cause the inner metal shell to be melted and a part thereof formed into a thin metal jet which is propelled through the front of the body to produce vaporization of the surrounding water.
Inventors
👤 R Levamaki
👤 M Vehvilainen
👤 T Suhonen
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-05 19:50
CPC Classifications
F; F42; F42B; F42B3/00; F42B3/08
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
187 words
A method for carrying out underwater demolition work comprising forming a hollow charge constituted as a hollow body with a front, a back, an outer shell of frustoconical shape And an inner metal shell of conical shape, mounting the shells so that they diverge towards the front and define a space between the shells containing an explosive charge, mounting a cover of flexible plastic material on the outer shell on the back of the body, mounting a base of flexible plastic material on the front of the body, forming said base with a U-shaped rim which joins the shells at the front of the body and is flexed in place thereat, mounting in said cover a detonator which extends in the space between the shells, placing the hollow charge underwater on the submerged surface to be blasted and igniting the detonator to effect detonation of the explosive charge in the hollow body to cause the inner metal shell to be melted and a part thereof formed into a thin metal jet which is propelled through the front of the body to produce vaporization of the surrounding water.
Claim 2
Independent Claim
187 words
A method for carrying out underwater demolition work comprising forming a hollow charge constituted as a hollow body with a front, a back, an outer shell of frustoconical shape And an inner metal shell of conical shape, mounting the shells so that they diverge towards the front and define a space between the shells containing an explosive charge, mounting a cover of flexible plastic material on the outer shell on the back of the body, mounting a base of flexible plastic material on the front of the body, forming said base with a U-shaped rim which joins the shells at the front of the body and is flexed in place thereat, mounting in said cover a detonator which extends in the space between the shells, placing the hollow charge underwater on the submerged surface to be blasted and igniting the detonator to effect detonation of the explosive charge in the hollow body to cause the inner metal shell to be melted and a part thereof formed into a thin metal jet which is propelled through the front of the body to produce vaporization of the surrounding water.
Claim 3
Dependent Claim
14 words
A method as claimed in claim 1 wherein the explosive charge is ammonium nitrate.
Claim 4
Dependent Claim
20 words
A method as claimed in claim 1 wherein said explosive has a detonation wave speed of less than 5,000 m/s.
Claim 5
Dependent Claim
17 words
A method as claimed in claim 1 wherein the inner metal shell is made of steel plate.