Mechanically collapsible shell for long cylinder production
A system for removing a cured composite object from a mandrel is provided. The system includes a collapsible shell, wherein an inner surface of the shell is configured to slide over an outer surface of the mandrel and an outer surface of the shell is configured to have the composite object formed thereon. The system further includes an extractor comprising a first and second disk disposed along a rod, and an adjuster, wherein the second disk is configured to engage an end of the mandrel and the adjuster is configured to move the first disk along the rod relative to the second disk. The system further includes a spacer configured to fit between the first disk and a first end of the shell when the shell is placed on the mandrel. The spacer pushes the shell and the composite object formed thereon off of the mandrel when the adjuster moves the first disk towards the second disk.
1. A system for removing a cured composite object from a mandrel, the system comprising:
a collapsible shell, wherein an inner surface of the shell is configured to slide over an outer surface of the mandrel and an outer surface of the shell is configured to have the composite object formed thereon;
an extractor comprising a first and second disk disposed along a rod, and an adjuster, wherein the second disk is configured to engage an end of the mandrel and the adjuster is configured to move the first disk along the rod relative to the second disk; and
a spacer configured to fit between the first disk and a first end of the shell when the shell is placed on the mandrel, and to push the shell and the composite object formed thereon off of the mandrel when the adjuster moves the first disk towards the second disk.
2. The system of claim 1 , wherein the composite object comprises composite fabric and the outer surface of the shell comprises a mold surface for lay-up of the composite fabric.
3. The system of claim 2 , wherein the outer surface of the shell comprises a positive draft angle.
4. The system of claim 2 , wherein the outer surface of the shell comprises a protrusion.
5. The system of claim 1 , wherein the first disk has a diameter that is larger than an outer diameter of the mandrel.
6. The system of claim 1 , wherein the second disk has a diameter that is smaller than an outer diameter of the mandrel and larger than an inner diameter of the mandrel.
7. The system of claim 1 , wherein the adjuster has a threaded portion adapted to engage the first disk.
8. The system of claim 7 , wherein the shell has a longitudinal length and the threaded portion has a threaded length greater or equal to the longitudinal length of the shell.
9. The system of claim 1 , wherein an inner surface of the shell comprises channels configured to reduce a contact surface area between the shell and the mandrel.
10. The system of claim 1 , wherein the shell comprises at least two flexible longitudinal sections and two or more edges of each longitudinal section are beveled.
11. The system of claim 1 , further comprising a disassembly sleeve configured to remove the shell from the composite object as the shell and the composite object are pushed off of the mandrel by the spacer.
12. The system of claim 11 , wherein the disassembly sleeve comprises a first and second opening configured to receive a first and second longitudinal section of the shell, respectively.
13. The system of claim 12 , further comprising a disassembly ring disposed at a distal portion of the disassembly sleeve and configured to receive a third and fourth longitudinal section of the shell between the disassembly ring and the disassembly sleeve.
14. A method for removing a cured composite object from a mandrel, the method comprising:
disposing a collapsible shell on an outer surface of the mandrel;
forming the composite object on an outer surface of the shell;
inserting an extractor through the mandrel, wherein the extractor comprises a first and second disk disposed along a rod, and an adjuster, wherein the second disk is configured to engage an end of the mandrel, and the adjuster is configured to move the first disk along the rod relative to the second disk;
disposing a spacer between the first disk and a first end of a shell; and
moving the first disk towards the second disk using the adjuster such that the spacer pushes the shell and the composite object formed thereon off of the mandrel.
15. The method of claim 14 , wherein the composite object comprises a composite fabric and the outer surface of the shell comprises a mold surface for lay-up of the composite fabric.
16. The method of claim 15 , wherein the outer surface of the shell has a positive draft angle.
17. The method of claim 15 , wherein the outer surface of the shell has a protrusion.
18. The method of claim 14 , wherein the adjuster has a threaded portion adapted to engage the first disk.
19. The method of claim 18 , wherein the shell has a longitudinal length and the threaded portion has a threaded length greater or equal to the longitudinal length of the shell.
20. The method of claim 14 , further comprising guiding a first and second longitudinal section of the shell into a corresponding first and second opening of a disassembly sleeve, wherein the disassembly sleeve pulls the first and second longitudinal sections of the shell away from the composite object as the spacer pushes the shell and the composite object formed thereon off of the mandrel.