Core Release System and Method

Abstract

A core release system 10 has a housing 28 provided with an impact member 30 arranged to impact a core sample 16 gripped in a core tube 12. The housing 10 can be fitted over an end of the core tube 12 in which a core sample is gripped. The impact member is arranged to deform in preference to the core sample 16. By applying a force to the housing 28 or the tube 12 which causes impact of the core sample 16 on the impact member 28 the core sample is displaced relative to, and released from the grip of, the tube 12.

What is claimed is: 
     
         1 . A core release system comprising: a housing provided with an impact member, the housing capable of receiving an end of a tube in which a core sample is gripped, the system arranged so that on applying a force to cause impact between the core sample and the impact member the core sample is displaced relative to the tube. 
     
     
         2 . The system according to  claim 1  wherein the impact member is arranged to deform in preference to the core sample. 
     
     
         3 . The system according to  claim 1  wherein the impact member is configured to fit within the tube. 
     
     
         4 . The system according to  claim 1  wherein the impact member is provided with an impact face configured to impact with the core sample at a location inboard of a circumferential peripheral edge of the core sample. 
     
     
         5 . The system according to  claim 1  wherein the impact member comprises a shock absorbing mechanism. 
     
     
         6 . The system according to  claim 1  wherein the impact member is movably mounted on the housing wherein the force displaces the impact member relative to the housing. 
     
     
         7 . The system according to  claim 1  wherein the housing is arranged to enable self-supported coupling to the tube. 
     
     
         8 . The system according to  claim 7  comprising a coupling mechanism arranged to facilitate coupling of the housing with the tube enabling the housing to be self-supported on the tube. 
     
     
         9 . The system according to  claim 8  wherein the coupling mechanism is arranged to allow the housing to move relative to the tube in response to application of the force. 
     
     
         10 . The system according to  claim 8  wherein the coupling mechanism comprises:
 (a) one or more magnets provided on one or both of the housing and the tube; or (b) a resilient member configured to act between an inside surface of the housing and an outer surface of the tube; or (c) a cam lock mechanism arranged to operate by relative rotation between the housing and the core lifter case. 
 
     
     
         11 . The system according to  claim 10  wherein the resilient member comprises an O-ring supported inside of the housing. 
     
     
         12 . The system according to  claim 1  comprising a visual indicator arranged to provide a visual indication to a user of the system of an amount of displacement of a core sample into the tube subsequent to being impacted with the impact member. 
     
     
         13 . The system according to  claim 12  wherein the visual indicator comprises a window formed in the housing at a location enabling viewing of the impact member. 
     
     
         14 . The system according to  claim 13  wherein the window is further configured to enable visualisation of the tube at least when impact between the core sample and the impact member has displaced the core sample into the tube a distance sufficient to release sample from the grip of the tube. 
     
     
         15 . The system according to  claim 14  wherein the window and the impact member are arranged so that when the core sample has been displaced the sufficient distance only the core tube is visible through the window. 
     
     
         16 . The system according to  claim 1  wherein the housing comprises a sleeve and a cap demountably coupled to an end of the sleeve, the impact member being coupled to the cap. 
     
     
         17 . The system according to  claim 1  wherein the tube comprises: a core lifter case; or, a core tube; or a core tube to which a core lifter case is attached. 
     
     
         18 . A method of releasing a core sample from a tube, the method comprising:
 locating a housing over an end of the tube in which a core sample is gripped; and   impacting the core sample with an impact member carried by the housing.   
     
     
         19 . The method according to  claim 18  comprising arranging the impact member to deform when impacted by the core sample. 
     
     
         20 . The method according to  claim 19  comprising configuring the impact member to fit inside of the tube. 
     
     
         21 . The method according to of  claim 18  comprising impacting the core sample with the impact member at a location inboard of a circumferential peripheral edge of the core sample. 
     
     
         22 . The method according to  claim 18  wherein locating the housing over an end of the tube comprising coupling the housing to the tube in a self-supporting manner. 
     
     
         23 . The method according to  claim 22  wherein coupling the housing comprises (a) magnetically coupling the housing to the tube; or (b) mechanically coupling the housing to the tube. 
     
     
         24 . The method according to  claim 18  comprising providing a visual indicator indicative of an amount of displacement of the core sample into the tube as a result of the impacting. 
     
     
         25 . The method according to  claim 24  wherein the impacting comprising repeatedly impacting the core sample with the impact member until the visual indicator provides an indication that the core sample has been displaced a distance sufficient to release the core sample from the grip of the tube. 
     
     
         26 . The method according to  claim 18  wherein the tube comprises: a core lifter case; or, a core tube; or a core tube to which a core lifter case is attached.