US 4,133,460 A · Apparatus embodying explosively removable sleeve

Abstract

A housing for an elongated opening such as a cylindrical passage which has a portion subject to severe conditions such as abrasion, heat, pressure, wear or corrosion which tend to deteriorate the wall of said opening, has a replaceable sleeve in the opening only at the portion exposed to such severe conditions. The housing, illustrated as a metal barrel for a plastic injection molding apparatus, has an elongated aperture or bore having a cross section larger than the desired cross section of the passage. A metal tubular inner sleeve defining the passage is held in the bore of the housing by a tight fit. The sleeve has at least one groove extending longitudinally on the exterior of the sleeve which forms a cavity with the housing wall. The end of the groove at at least the exposed end of the sleeve is closed by a closure portion or ridge. The sleeve can be removed by drilling a hole through the closure portion to permit access to the groove cavity and permit introduction of explosive material into the cavity. Detonating of the explosive material causes the sleeve to collapse, as by fracture into a plurality of pieces, internally of the bore, permitting the sleeve to be easily removed from the housing bore. A replacement sleeve can then be inserted without machining of the housing of the sleeve. Various types of sleeves, and methods of removing and replacing the sleeve are disclosed.

Claims23

Dependent claims

In combination, a rigid housing for receiving a sleeve having an elongated opening the surface of which is subject to severe conditions in use, a portion of the housing having an elongated aperture surrounded by a substantially thick wall, said aperture having a cross section larger than the cross section of said sleeve opening;

said sleeve having the surface of said opening formed of material resistant to said severe conditions, said sleeve being inserted and fixed without bonding within said aperture of said housing and having at least one groove formed in and extending uninterruptedly along the exterior of the sleeve substantially throughout its length but terminating short of an end thereof to form an ungrooved end portion, said groove defining with the adjacent portion of said aperture wall an elongated cavity between said sleeve and said aperture wall that is closed throughout the length of the groove and that is capable of having explosive material inserted into said cavity substantially throughout its length, the relative strengths of said sleeve and said housing and the cross section of said groove being such that when said explosive material in said cavity is detonated said sleeve fractures at said groove and collapses inwardly of said aperture without injury to said housing to permit ready removal of the collapsed sleeve from said aperture in said housing.

In combination, a rigid housing for receiving a tubular sleeve having an elongated cylindrical opening subject to abrasion or wear, which housing has a portion having an elongated cylindrical aperture surrounded by a substantially thick wall, said aperture having a diameter larger than the diameter of said opening;

said tubular sleeve having an external cylindrical surface of a size and shape such that it fits tightly within said cylindrical aperture without bonding, said sleeve having at least one groove formed in and extending uninterruptedly along the exterior of said sleeve substantially throughout its length but terminating short of an end thereof to provide a closure portion between said end of the groove and the associated end of the sleeve accessible from an exterior end of said housing, said groove and the adjacent inner wall of said aperture forming an elongated cavity between said sleeve and said aperture wall that is closed throughout the length of the groove and that is capable of having explosive material inserted into the cavity substantially throughout its length after an opening has been formed through said closure portion, the relative strengths of said sleeve and said housing and the cross section of said groove being such that when said explosive material in said cavity is detonated said sleeve fractures at said groove and collapses inwardly of said aperture without injury to said housing to permit ready removal of the collapsed sleeve from said aperture in said housing.

Dependencies are inferred from the claim text.

Apparatus embodying explosively removable sleeve

Life of this patent

Apparatus embodying explosively removable sleeve

Life of this patent

Abstract

Claims23