Modular Downhole Junk Basket Assembly

Abstract

A modular junk basket assembly adapted for attachment to a wellbore tubing string comprises a tubular body having a plurality of debris ports that feed into an integrally formed basket space. A baffle is slidably mounted on the tubular body which translates along the length of the tubular body to a position behind the debris ports, relative to the fluid pressure created on the baffle. The baffle has a plurality of fluid passageways which allow passage of drilling fluid and small debris as larger debris is diverted toward the debris ports and into the debris basket.

We claim: 
     
         1 . A modular junk basket assembly comprising:
 (a) a longitudinally extending tubular tool body having a central through-bore, an upper end, and a lower end;   (b) a debris basket within said tool body;   (c) a plurality of radially distributed debris ports in communication with said debris basket; and   (d) a ring-shaped baffle slidably mounted around said longitudinally extending tool body, said baffle slidably translatable along said longitudinally extending tool body across said plurality of debris ports.   
     
     
         2 . The modular junk basket assembly recited in  claim 1 , wherein said debris ports are positioned between a first shoulder positioned at the periphery of said tool body and a second shoulder positioned at the periphery of said tool body whereby said baffle is slidably translatable between said first and second shoulders. 
     
     
         3 . The modular junk basket assembly recited in  claim 2 , wherein said baffle has a plurality of flow slots. 
     
     
         4 . The modular junk basket assembly recited in  claim 3 , wherein said flow slots are radially spaced around the periphery of said baffle. 
     
     
         5 . The modular junk basket assembly recited in  claim 3 , wherein said flow slots are holes through said baffle. 
     
     
         6 . The modular junk basket assembly recited in  claim 4 , wherein said flow slots are U-shaped. 
     
     
         7 . The modular junk basket assembly recited in  claim 3 , wherein said baffle has an inwardly angled wall. 
     
     
         8 . A modular junk basket assembly comprising:
 (a) a longitudinally extending tubular tool body having a central through-bore, an upper end, and a lower end;   (b) a debris basket within said tool body;   (c) a plurality of radially distributed debris ports in communication with said debris basket;   (d) a first shoulder on the periphery of said tool body;   (e) a second shoulder on the periphery of said tool body;   (f) a retaining structure at the periphery of said tool body positioned between said first shoulder and said second shoulder; and   (g) a first ring-shaped baffle slidably mounted around said longitudinally extending tool body and a second ring-shaped baffle slidably mounted around said longitudinally extending tool body, said first and second baffles releasably restrained against said retaining structure.   
     
     
         9 . The modular junk basket assembly recited in  claim 8 , wherein said first and second baffles have a plurality of equally spaced flow gaps along the radial periphery of said baffles, said flow gaps providing a plurality of fluid flow space across each of said first and second baffles. 
     
     
         10 . The modular junk basket assembly recited in  claim 9 , wherein said first and said second ring-shaped baffles are oriented on said tool body to stagger said flow gaps and close said fluid flow space across each of said first and second baffles. 
     
     
         11 . The modular junk basket assembly recited in  claim 10 , wherein said first and second baffles are slideably retained on linear slides. 
     
     
         12 . The modular junk basket assembly recited in  claim 11 , wherein said first and second baffles are releasably restrained by shear screws or by shear pins. 
     
     
         13 . The modular junk basket assembly recited in  claim 11 , wherein said first and second baffles are releasably restrained by compression springs. 
     
     
         14 . A method of removing debris from fluid in a wellbore, comprising the steps of:
 (a) providing a junk basket assembly comprising:
 (i) a longitudinally extending tubular tool body having a central through-bore, an upper end, and a lower end; 
 (ii) a debris basket within said tool body; 
 (iii) a plurality of radially distributed debris ports in communication with said debris basket; and 
 (iv) a ring-shaped baffle slidably mounted around said longitudinally extending tool body, said baffle slidably translatable along said longitudinally extending tool body across said plurality of debris ports; 
   (b) attaching said junk basket assembly to a tubing string;   (c) inserting said tubing string with said attached junk basket assembly into a wellbore thereby creating a annular space for wellbore fluid between said wellbore and said junk basket assembly; and   (d) providing an upward flow of wellbore fluid in said annular space, said wellbore fluid carrying wellbore debris, whereby fluid pressure on said baffle slides said baffle to a position upward from said fluid ports thereby diverting at least some of said debris in said wellbore fluid through said plurality of debris ports and into said debris basket.   
     
     
         15 . The method of  claim 14 , further comprising the step of providing a downward flow of wellbore fluid in said annular space, said wellbore fluid carrying wellbore debris, whereby fluid pressure on said baffle slides said baffle to a position downward from said fluid ports thereby diverting at least some of said debris in said wellbore fluid through said plurality of debris ports and into said debris basket. 
     
     
         16 . The method as recited in  claim 15  further comprising the step of providing said baffle with a plurality of flow slots, said flow slots allowing said wellbore fluid and a least some wellbore debris to flow through said slots. 
     
     
         17 . A method of removing debris from fluid in a wellbore, comprising the steps of:
 (a) providing a junk basket assembly comprising:
 (i) a longitudinally extending tubular tool body having a central through-bore, an upper end, and a lower end; 
 (ii) a debris basket located within said tool body; 
 (iii) a plurality of radially distributed debris ports in communication with said debris basket; 
 (iv) a first shoulder extending radially around the periphery of said tool body; 
 (v) a second shoulder extending radially around the periphery of said tool body; 
 (vi) a first releasably restrained ring-shaped baffle slidably mounted around said longitudinally extending tool body and a second releasably restrained ring-shaped baffle slidably mounted around said longitudinally extending tool body; and 
 (vii) a retaining structure between said first shoulder and said second shoulder, said retaining structure sandwiched by said first and said second releasably restrained baffles; 
   (b) attaching said junk basket assembly to a tubing string;   (c) inserting said tubing string with said attached junk basket assembly into a wellbore thereby creating a annular space for wellbore fluid between said wellbore and said junk basket assembly;   (d) providing an upward flow of wellbore fluid in said annular space, said wellbore fluid carrying wellbore debris, whereby at least a portion of said wellbore debris is diverted by said first and second baffles into said debris basket; and   (e) wherein when fluid pressure of said upward flow of wellbore fluid on said first and second baffles reaches a predetermined pressure force, said releasably restrained first baffle is released to slidably translate away from said second baffle thereby creating a flow space between said first baffle and said second baffle.   
     
     
         18 . The method of  claim 17 , further comprising the step of providing a downward flow of wellbore fluid in said annular space, said wellbore fluid carrying wellbore debris, said wellbore fluid carrying wellbore debris, whereby at least a portion of said wellbore debris is diverted by said first and second baffles into said debris basket, wherein when fluid pressure on said first and second baffles reaches a predetermined pressure force, said releasably restrained second baffle is released to slidably translate away from said first baffle thereby creating a flow space between said first baffle and said second baffle. 
     
     
         19 . The method of  claim 18  wherein said first ring-shaped baffle and said second ring-shaped baffle have a plurality of flow gaps. 
     
     
         20 . The method as recited in  claim 19  wherein said first ring-shaped baffle and said second ring-shaped baffle are oriented on said tool body whereby said flow gaps of said first and said second baffles are closed.