Method for the development and quality control of flow-optimized shaped charges
View Patent ↗An improved test setup facility, referred to as a “Quick Development Cell” (QDC), which allows for rapid turnaround testing with valuable feedback to a design engineer. Because the QDC allows for quick and efficient testing at a sufficient frequency, QDC tests are compatible with production quality control. In addition to fostering improvement of the API's Section 2 type tests using stressed natural rock for benchmark experiments, the QDC tests allow for progress to be made towards the development of a flow-optimized shape charge and superior well performance.
1. An apparatus for the rapid testing of shaped charges on a rock target, the apparatus comprising:
a) an overburdening chamber having an open end for accepting a rock target;
b) a retractable ejector located within the overburdening chamber at an end opposite to the open end, the ejector retracting to create a space for receiving of a rock target into the overburdening chamber;
c) a casing plate and a cement plate configured to cover the open end of the overburdening chamber; and
d) a charge stack mounted to the overburdening chamber and creating a pressure seal for the overburdening chamber, wherein said charge stack comprises a clearance ring simulating gun-to-casing clearance and a standoff ring simulating charge-to-gun clearance;
whereby rapid removal of a rock target from the overburdening chamber is facilitated by the retractable ejector.
2. The apparatus of claim 1 , wherein the rock target comprises natural rock.
3. The apparatus of claim 1 , wherein the rock target comprises stressed rock.
4. The apparatus of claim 1 , wherein the rock target comprises Berea sandstone.
5. The apparatus of claim 1 further comprising a sleeve for accepting the rock target.
6. The apparatus of claim 5 wherein the sleeve is flexible.
7. The apparatus of claim 1 further comprising a retaining ring for securing the cement plate and casing plate to the open end of the overburdening chamber.
8. A simulation method for the development of flow-optimized shaped charges and perforation geometry to maximize flow performance, said simulation method comprising the steps of:
retracting an ejector located within an overburdening chamber to create a space for insertion of a rock target within the overburdening chamber;
loading a rock target into the created space in the overburdening chamber;
sealing an open end of the overburdening chamber with a casing plate and a cement plate;
mounting a charge stack comprising a charge on an opposite side of the casing plate from the rock target;
pressurizing said overburdening chamber to simulate downhole conditions; and
detonating the charge;
depressurizing said overburdening chamber; and
ejecting the rock target with the ejector.
9. The method of claim 8 , further comprising the step of:
collecting data from the detonation of said charge.
10. The method of claim 8 , further comprising the step of:
unloading said rock target and repeating said method steps commencing with retracting the ejector to create a space for insertion of another rock target within the overburdening chamber.
11. The method of claim 8 , wherein the pressurizing of said overburdening chamber occurs at approximately 6,000 psi.
12. The method of claim 8 , further comprising surrounding the loaded rock target and said cement plate by a flexible sleeve.
13. An apparatus for the rapid testing of shaped charges on a rock target, the apparatus comprising:
a first chamber sized to receive a rock target therein, the first chamber having a first end sized for accepting a rock target;
a retractable ejector located within the first chamber at an end opposite the first end, the ejector retracting to create a space to receive a rock target into the first chamber;
a cement plate configured to face a contained rock target and seal off the first end of the first chamber;
a casing plate backing the cement plate;
a second chamber mounted to the first chamber around the casing plate, the second chamber creating a pressure seal for the first chamber, the second chamber comprising a charge stack, the charge stack having a first clearance ring simulating gun-to-casing clearance, and a second clearance ring simulating charge-to-gun clearance; and
a sleeve configured to surround a rock target and to extend to the casing plate;
whereby rapid removal of a rock target after testing is facilitated by the retractable ejector.