Locking apparatus with packoff capability

Abstract

A well tool locking apparatus compatible with high temperature, high pressure well conditions comprises a packing ring mandrel that carries a sliding locking dog cage. The locking dogs are expanded radially into a tubing nipple channel by the axial translation of a ramped step on the mandrel surface. Chevron ring packing seals are positioned between the locking dog cage and an abutment shoulder around the mandrel. Translation of the mandrel against the locking dog cage engages the tool locking dogs and expands the chevron ring seal against the inside bore surface of the tubing nipple. The locked and sealed position is held by buttress threads on the mandrel engaged with a body lock ring

1 . A locking apparatus that is releasably securable within a landing nipple of a tubing string, the locking apparatus comprising: 
 a tool housing with an associated inner mandrel;    a locking member that is radially moveable with respect to the tool housing, the locking member being selectively disposable into a landing nipple receptacle to secure the locking apparatus within the tubing string;    a packing seal retained upon the inner mandrel, the packing seal being axially compressible; and    a compression member associated with the tool housing for selective axial compression of the packing seal to urge the packing seal into sealing engagement with the tubing string.    
     
     
         2 . The locking apparatus of  claim 1  wherein the tool housing is interconnectable with well control tools.  
     
     
         3 . The locking apparatus of  claim 1  wherein the compression member is actuated to compress the packing seal by axially translating the inner mandrel with respect to the tool housing.  
     
     
         4 . The locking apparatus of  claim 1  wherein the packing seal comprises a chevron packing seal member.  
     
     
         5 . The locking apparatus of  claim 1  wherein the packing seal comprises a multiple chevron seal members in a stacked configuration.  
     
     
         6 . The locking apparatus of  claim 1  further comprising a locking dog cage and wherein the locking member comprises a locking dog that is urged radially outwardly through a slot in the locking dog cage.  
     
     
         7 . The locking apparatus of  claim 6  wherein the compression member comprises a ram end of the locking dog cage.  
     
     
         8 . The locking apparatus of  claim 1  wherein the packing seal comprises a dynamic seal assembly.  
     
     
         9 . A locking apparatus that is releasably securable within a landing nipple of a tubing string, the locking apparatus comprising: 
 a tool housing with an associated inner mandrel;    a locking member that is radially moveable with respect to the tool housing, the locking member being selectively disposable into a landing nipple receptacle to secure the locking apparatus within the tubing string;    a packing seal retained upon the inner mandrel, the packing seal being axially compressible;    a compression member associated with the tool housing for selective axial compression of the packing seal to urge the packing seal into sealing engagement with the tubing string; and    a locking dog cage and wherein the locking member comprises a locking dog that is urged radially outwardly through a slot in the locking dog cage.    
     
     
         10 . The locking apparatus of  claim 9  wherein the compression member is actuated to compress the packing seal by axially translating the inner mandrel with respect to the tool housing.  
     
     
         11 . The locking apparatus of  claim 9  wherein the packing seal comprises a chevron packing seal member.  
     
     
         12 . The locking apparatus of  claim 9  wherein the packing seal comprises a multiple chevron seal members in a stacked configuration.  
     
     
         13 . The locking apparatus of  claim 9  wherein the packing seal comprises a dynamic seal assembly.  
     
     
         14 . The locking apparatus of  claim 9  wherein the compression member comprises a ram end of the locking dog cage.  
     
     
         15 . A method of securing a locking apparatus within a tubing string comprising the steps of: 
 disposing the locking apparatus within a tubing string to a location adjacent a landing nipple;    moving a locking member radially outwardly from the locking apparatus and into locking engagement with a landing nipple receptacle; and    axially compressing a packing seal on the locking apparatus to urge the packing seal radially outwardly into sealing engagement with the tubing string.    
     
     
         16 . The method of  claim 15  further comprising the step of securing the locking apparatus to at least one well control tool prior to disposing the locking apparatus in the tubing string.