Wellbore casing and method of forming same

Abstract

A method of forming a well bore casing for insertion in a well bore, according to which a first casing section is coupled to a second casing section and a seal is provided between the coupled portions of the sections.

1 . A well bore casing for insertion in a well bore, the casing comprising: 
 a first casing section;    a second casing section coupled to the first casing section; and    a sleeve extending in a coaxial relationship with the coupled sections and in an overlapping relation to at least a portion of the sections,    the sleeve adapted to melt in response to the application of energy to the sleeve and flow around the joint between the coupled sections to produce a surface-to-surface air tight metallic seal.    
   
   
       2 . The casing of  claim 1  further comprising threads provided on the first casing section, and threads provided on the second casing section that engage the threads on the first casing section to couple the sections, and wherein the melted sleeve flows around at least a portion of the threaded sections.  
   
   
       3 . The casing of  claim 1 , wherein the sleeve extends around the casing sections, and wherein the energy causes the sleeve to collapse against the sections before it melts.  
   
   
       4 . The casing of  claim 1 , wherein the sleeve extends within the casing sections and wherein the energy causes the sleeve to expand against the casing sections before it melts.  
   
   
       5 . The casing of  claim 1  wherein a portion of the first casing section is coupled to a portion of the second casing section, and wherein at least a portion of the sleeve extends in an overlapping relation to the coupled portions of the casing sections.  
   
   
       6 . The casing of  claim 1  wherein a channel is defined between the casing sections and wherein a portion of the melted sleeve flows into the channel.  
   
   
       7 . The casing of  claim 1  further comprising an apparatus disposed proximate to the casing sections for producing the energy in the form of a magnetic impulse.  
   
   
       8 . The casing of  claim 1  wherein the diameter of an end portion of one casing section is less that that of the remaining portion of the one casing, and wherein the diameter of an end portion of the other casing section is greater than that of the remaining portion of the other casing section and interlocks with the end portion of the one casing section to couple the sections.  
   
   
       9 . The casing of  claim 8  further comprising at least one raised ridge ring extending radially from the end portion of one casing section and into a groove formed in the end portion of the other casing section.  
   
   
       10 . A well bore casing for insertion in a well bore, the casing comprising: 
 a first casing section having a threaded portion;    a second casing section having a threaded portion threadedly engaging the threaded portion of the first casing section to couple the sections;    a space defined between the coupled threaded portions; and    an insert disposed in the space for providing a seal between the coupled threaded portions.    
   
   
       11 . The casing of  claim 10 , wherein the insert comprises a metallic material  
   
   
       12 . The casing of  claim 10  wherein the insert comprises a first layer having a first modulus of elasticity; and at least one additional layer having a second modulus of elasticity that is different from the first modulus of elasticity.  
   
   
       13 . The casing of  claim 12 , wherein one of the layers comprises copper; and wherein the other layer comprises cadmium.  
   
   
       14 . The casing of  claim 12 , wherein the modulus of elasticities of the layers are less than the modulus of elasticities of the casing sections.  
   
   
       15 . The casing of  claim 12  wherein one of the layers provides a fluidic seal; and wherein the other layer provides a micro fluidic seal.  
   
   
       16 . The casing of  claim 10  further comprising a sleeve extending in a coaxial relationship with the casing sections and in an overlapping relation to at least a portion of the threaded portions of the sections; the sleeve adapted to melt in response to the application of external energy to the sleeve and flow around the joint between the threaded portions to produce a surface-to-surface air tight metallic seal over the threaded portions.  
   
   
       17 . A well bore casing for insertion in a well bore, the casing comprising: 
 a first casing section having a tapered end portion; and    a second casing section having a flared end portion extending over the tapered end portion; and a material extending between the tapered end portion and the flared end portion to couple the casing sections.    
   
   
       18 . The casing of  claim 17  wherein the material flashes in response to it increasing in temperature caused by rotation of at least one casing section.  
   
   
       19 . The casing of  claim 17  further threads formed on the tapered end portion, and threads formed on the flared end portion and in engagement with the threads on the tapered end portion.  
   
   
       20 . A method of forming a well bore casing for insertion in a well bore, the method comprising: 
 coupling a first casing section to a second casing section;    positioning a sleeve extending in an overlapping relation to at least a portion of the sections; and    melting the sleeve so that it flows around the joint between the coupled sections to produce a surface-to-surface air tight metallic seal.    
   
   
       21 . The method of  claim 20  wherein the step of coupling comprises placing the sections in a threaded engagement, and flowing the melted sleeve around at least a portion of the threaded sections.  
   
   
       22 . The method of  claim 20 , wherein the sleeve extends around the casing sections, and further comprising collapsing the sleeve against the sections before the step of melting.  
   
   
       23 . The method of  claim 20 , wherein the sleeve extends within the casing sections and further comprising expanding the sleeve against the sections before the step of melting.  
   
   
       24 . The method of  claim 20  wherein a portion of the first casing section is coupled to a portion of the second casing section, and wherein at least a portion of the sleeve extends in an overlapping relation to the coupled portions of the casing sections.  
   
   
       25 . The method of  claim 20  further comprising forming a channel between the casing sections, and wherein a portion of the melted sleeve flows into the channel.  
   
   
       26 . The method of  claim 20  further comprising applying energy, in the form of a magnetic impulse, to the sleeve to melt it.  
   
   
       27 . The method of  claim 20  wherein the diameter of an end portion of one casing section is less that that of the remaining portion of the one casing, and the diameter of an end portion of the other casing section is greater than that of the remaining portion of the other casing section, and wherein the step of coupling comprises interlocking the end portions.  
   
   
       28 . The method of  claim 20  further comprising inserting at least one raised ridge ring extending radially from the end portion of one casing section and into a groove formed in the end portion of the other casing section.  
   
   
       29 . The method of  claim 20  further comprising the step of expanding the casing sections radially outwardly towards the wall of the well bore.  
   
   
       30 . A method of forming a well bore casing, the method casing comprising: 
 providing threads on a portion of a first casing section;    providing threads on a portion of a second casing section;    engaging the threads on the first casing section portion with the threads on the second casing section portion to couple the sections; the threads being sized so as to form a gap between the engaged threads; and    disposing an insert in the gap for providing a seal between the engaged threads.    
   
   
       31 . The method of  claim 30  wherein the insert is a metallic material.  
   
   
       32 . The method of  claim 30  wherein the insert is formed by a first layer having a first modulus of elasticity; and at least one additional layer having a second modulus of elasticity that is different from the first modulus of elasticity.  
   
   
       33 . The method of  claim 32  wherein one of the layers is copper; and wherein the other layer is cadmium.  
   
   
       34 . The method of  claim 32  wherein the modulus of elasticities of the layers are less than the modulus of elasticities of the casing sections.  
   
   
       35 . The method of  claim 32  wherein one of the layers provides a fluidic seal; and wherein the other layer provides a micro fluidic seal.  
   
   
       36 . The method of  claim 30  further comprising disposing a sleeve in a coaxial relationship with the casing sections and in an overlapping relation to at least a portion of the threads; and melting the sleeve so that it flows around the joint between the threaded portions to produce a surface-to-surface air tight metallic seal over the threaded portions.  
   
   
       37 . The method of  claim 36  wherein the step of melting comprises applying energy to the sleeve.  
   
   
       38 . The method of  claim 36  wherein the step of melting comprises applying magnetic impulses to the sleeve.  
   
   
       39 . The method of  claim 30  further comprising the step of expanding the casing sections radially outwardly towards the wall of the well bore.  
   
   
       40 . A method of forming a well bore casing, the casing comprising: 
 positioning a tapered end portion of a first casing section over a flared end portion of a second casing section; and    providing a material between the end portions; and    increasing the temperature of the material to flash the material and couple the sections.    
   
   
       41 . The method of  claim 40  further comprising rotating at least one of the casing sections to increase the temperature of the material and flash the material.  
   
   
       42 . The method of  claim 40  wherein threads are formed on the tapered end portion and threads are formed on the flared end portion, and further comprising engaging the threads.  
   
   
       43 . The method of  claim 40  further comprising the step of expanding the casing sections radially outwardly towards the wall of the well bore.