Snubber for Downhole Tool

Abstract

An apparatus for reducing mechanical shock and vibration in a downhole tool includes a frustum-shaped sleeve configured to be disposed between the downhole tool and another downhole component. The frustum-shaped sleeve is made of a mechanical shock absorbing material and includes a central axis, a radially inner surface, and a radially outer surface. The radially inner surface or the radially outer surface of the frustum-shaped sleeve includes a pyramidal frustum-shaped surface with four or more circumferentially adjacent sides. The downhole tool or the downhole component has a pyramidal frustum-shaped surface configured to mate with the pyramidal frustum-shaped surface of the frustum-shaped sleeve.

What is claimed is: 
     
         1 . An apparatus for reducing mechanical shock and vibration in a downhole tool configured to be disposed in a borehole, the apparatus comprising:
 a frustum-shaped sleeve configured to be disposed between a downhole tool and another downhole component;   wherein the downhole tool and the downhole component are configured to mate with each other; and   wherein the frustum-shaped sleeve is made of a mechanical shock absorbing material and comprises:
 a central axis; 
 a radially inner surface; and 
 a radially outer surface; 
 wherein the radially inner surface or the radially outer surface of the frustum-shaped sleeve comprises a pyramidal frustum-shaped surface with four or more circumferentially adjacent sides; 
 wherein the downhole tool or the downhole component has a pyramidal frustum-shaped surface configured to mate with the pyramidal frustum-shaped surface of the frustum-shaped sleeve. 
   
     
     
         2 . The apparatus of  claim 1 , wherein the downhole component or the downhole tool has a frustum-shaped plug with an outer surface comprising the pyramidal frustum-shaped surface configured to receive the frustum-shaped sleeve and mate with the pyramidal frustum-shaped surface of the frustum-shaped sleeve. 
     
     
         3 . The apparatus of  claim 1 , wherein the downhole component comprises one of: another downhole tool and a centralizer. 
     
     
         4 . The apparatus of  claim 2 , wherein the mechanical shock absorbing material comprises a metal. 
     
     
         5 . The apparatus of  claim 1 ,
 wherein the frustum-shaped sleeve includes a first end and a second end opposite the first end;   wherein each of the plurality of sides of the pyramidal frustum-shaped surface of the frustum-shaped sleeve extends linearly from the first end to the second end.   
     
     
         6 . The apparatus of  claim 4 , wherein frustum-shaped plug is made of the same metal as the frustum-shaped sleeve. 
     
     
         7 . The apparatus of  claim 4 , wherein the mechanical shock absorbing material is selected to retain its temper in a temperature range of −50° C. to 175° C. 
     
     
         8 . The apparatus of  claim 1 , wherein the radially inner surface of the frustum-shaped sleeve comprises the pyramidal frustum-shaped surface of the frustum-shaped sleeve and the radially outer surface of the frustum-shaped sleeve is a conical frustum-shaped surface; or
 wherein the radially outer surface of the frustum-shaped sleeve comprises the pyramidal frustum-shaped surface of the frustum-shaped sleeve and the radially inner surface of the frustum-shaped sleeve is a conical frustum-shaped surface.   
     
     
         9 . The apparatus of  claim 1 , the frustum-shaped sleeve having an interior angle in a range of 5° to 80°. 
     
     
         10 . The apparatus of  claim 9 , the frustum-shaped sleeve having an interior angle in a range of 5° to 35°. 
     
     
         11 . The apparatus of  claim 10 , the frustum-shaped sleeve having an interior angle in a range of 8° to 28°. 
     
     
         12 . The apparatus of  claim 1 , wherein the downhole component or the downhole tool has a frustum-shaped receptacle with an inner surface comprising the pyramidal frustum-shaped surface configured to receive the frustum-shaped sleeve and mate with the pyramidal frustum-shaped surface of the frustum-shaped sleeve. 
     
     
         13 . The apparatus of  claim 1 , wherein the radially inner surface of the frustum-shaped sleeve comprises the pyramidal frustum-shaped surface and the radially outer surface of the frustum-shaped sleeve comprises a pyramidal frustum-shaped surface with four or more circumferentially adjacent sides;
 wherein the downhole tool or the downhole component has a pyramidal frustum-shaped surface configured to mate with the pyramidal frustum-shaped surface of the radially inner surface of the frustum-shaped sleeve; and   wherein the other of the downhole tool or the downhole component has a pyramidal frustum-shaped surface configured to mate with the pyramidal frustum-shaped surface of the radially outer surface of the frustum-shaped sleeve.   
     
     
         14 . An apparatus for operating in a borehole, the apparatus comprising:
 a downhole tool configured to perform an electronic operation;   a downhole component configured to interconnect with the downhole tool; and
 a frustum-shaped sleeve disposed between the downhole tool and the downhole component at the interconnection and comprising a mechanical shock absorbing material; 
   wherein one of the downhole tool and the downhole component has a frustum-shaped mating plug and the other one of the downhole tool and the downhole component has a mating receptacle configured to receive the mating plug, wherein the receptacle includes a first opening and a second opening; and   wherein the frustum-shaped mating plug is hollow and includes with an outer surface configured to receive the frustum-shaped sleeve;   a preload retainer configured to be partially inserted into a smaller of the first opening and the second opening of the mating receptacle, wherein the preload retainer comprises:
 a boss dimensioned to be larger than an inner diameter of the smaller of the first opening and the second opening, and 
 a tube with an outer diameter that is smaller than the inner diameter of the smaller of the first opening and the second opening. 
   
     
     
         15 . The apparatus of  claim 14 , wherein the mating plug includes an outer surface that further includes a plurality of separate axially spaced ridges and a plurality of axially spaced grooves interspaced between the plurality of ridges; and
 wherein each of the ridges and each of the grooves extend circumferentially about a central axis of the mating plug.   
     
     
         16 . The apparatus of  claim 14 , wherein the mating plug includes an outer surface that is smooth. 
     
     
         17 . The apparatus of  claim 14 , wherein the downhole component comprises one of: another downhole tool and a centralizer. 
     
     
         18 . The apparatus of  claim 14 , wherein the mechanical shock absorbing material comprises an elastomeric material. 
     
     
         19 . The apparatus of  claim 18 , wherein the elastomeric material has a durometer value between 10 A and 60 A. 
     
     
         20 . The apparatus of  claim 19 , wherein the elastomeric material has a durometer value of between 20 A and 40 A. 
     
     
         21 . The apparatus of  claim 19 , wherein the elastomeric material has a deformation point above 260° C. 
     
     
         22 . The apparatus of  claim 19 , wherein the elastomeric material retains is durometer value over a temperature range of −50° C. to 175° C. 
     
     
         23 . The apparatus of  claim 18 , wherein the elastomeric material is silicone. 
     
     
         24 . The apparatus of  claim 14 ,
 wherein the mechanical shock absorbing material of the frustum-shaped sleeve comprises a corrugated metal;   wherein the frustum-shaped sleeve has an axis; and   wherein the corrugated metal is one of:
 corrugated radially relative to the axis; and 
 corrugated longitudinally relative to the axis. 
   
     
     
         25 . The apparatus of  claim 24 , wherein the mechanical shock absorbing material is selected to retain its temper in a temperature range of −50° C. to 175° C. 
     
     
         26 . The apparatus of  claim 14 , wherein the frustum-shaped mating plug and the mating receptacle are configured to slidingly engage to form the interconnection.