US 7,600,476 B1
Geometric/mechanical apparatus to improve well perforator performance
Ernest L. Baker, Wantage, N.J. (US); and Arthur S. Daniels, Rockaway, N.J. (US)
Assigned to The United States of America as represented by the Secretary of the Army, Washington, D.C. (US)
Filed on Mar. 24, 2006, as Appl. No. 11/277,382.
Int. Cl. F42B 1/02 (2006.01)
U.S. Cl. 102—476  [102/306] 6 Claims
OG exemplary drawing
 
1. A shaped perforating charge for initiating flow from a well, comprising:
a case having a front portion with an open front end and a rear portion, an external surface and a longitudinal axis, all transverse cross-sections of the case being bi-symmetric;
said rear portion shaped in the form of a truncated cone with an open front, wherein the truncation of the cone forms said closed flat end of said case, said closed flat end being parallel to the open front end of said front portion, and wherein said closed flat end has a thickness greater than the thickness of the remainder of the cone;
said front portion being in the form of a cylinder, said cylinder having a front end and back end, said back end being continuously joined to the open front of said rear portion, wherein the cylinder has a thickness equal to the part of the front end of said rear portion to which it is joined;
said front end of said cylinder forming said open front end of said front portion, wherein said open front end is disposed in a plane which is substantially perpendicular to said longitudinal axis;
an explosive material disposed in the case, the case including a single ignition point formed by an opening within said closed flat end, extending from the external surface thereof to the explosive material for initiation of the explosive material, said opening being disposed symmetrically about said longitudinal axis; and
a liner disposed within said open front end, over the explosive material, the liner being conical in shape, wherein the apex of said conical shape is aligned with the longitudinal axis of said case and pointing towards said flat end of said case;
wherein a pair of substantially identical longitudinal slots are formed on the external surface, the longitudinal slots being about 180 degrees apart;
whereby when the explosion is initiated, a fan-like jet will result.