Autofrettage process and autofrettage apparatus
AssigneeMaximator GmbH
InventorsBernd Kampmann, Jochen Diemer
Life of this patent
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Abstract
In the autofrettage process, a thick-walled workpiece (2) to undergo autofrettage is positioned in an autofrettage apparatus (1). The interior space (5) of the workpiece (2) is filled with a fluid and closed so as to be pressure-tight. The volume available to the fluid in the interior space (5) of the workpiece (2) is reduced by a displacement piston (19) which is moved into the interior space (5) of the workpiece (2) through a displacement piston opening (6) of the workpiece (2). The pressure is therefore generated in the interior space (5) of the workpiece (2).
Claims7
An autofrettage process, wherein interior regions of a workpiece are permanently plastically deformed under high pressure, whereas exterior regions of the workpiece are only elastically deformed, the process comprising the steps of:
- placing a workpiece having an interior space and a displacement piston opening in an autofrettage apparatus,
- filling the interior space of the workpiece from below with a fluid through a pre-fill opening,
- closing the pre-fill opening with a closure piston,
- venting air from a region of the displacement piston opening, until the fluid flows out of the displacement piston opening of the workpiece disposed at a top of the workpiece,
- sealing the interior space of the workpiece by pressing a sealing sleeve surrounding the closure piston against a flange face of the workpiece so as to be pressure-tight, and
- advancing a displacement piston through the displacement piston opening into the interior space of the workpiece to reduce a volume available to the fluid in the interior space.
Dependencies are inferred from the claim text.