Magnetic pulse welding method and apparatus for sealing a vessel and a sealed vessel

Abstract

A method and a welding induction coil for sealing a vessel are provided. The method includes providing a vessel's body having an open end a cover including a welding part and a brim part. A diameter of the cover at the welding part is less than the inner diameter of the vessel's body for providing an air gap between the vessel's body and the welding part. The cover is placed within said open end of the vessel's body. A welding induction coil is provided around the vessel's body at the place where the welding part of the cover is located. The welding induction coil is energized to generate a pulsed magnetic force sufficient to cause bending a portion of the vessel's body in a radially inward direction around the cover in the air gap. The pulsed magnetic force has such a value so to provide mutual diffusion of atoms of the vessel's body and the cover at their impact, thereby to weld the vessel's body and the cover to each other.

1 . A method of sealing a vessel, comprising: 
 (a) providing a vessel's body having at least one an open end;    (b) providing a cover having a welding part, where said welding part has a diameter less than the inner diameter of the vessel's body;    (c) placing the cover within said at least one an open end of the vessel's body, thereby an air gap is formed between said vessel's body and the welding part of said cover;    (d) providing a welding induction coil around said vessel's body at the place where the welding part of the cover is located; and    (e) energizing said welding induction coil to generate a pulsed magnetic force sufficient to cause bending a portion of the vessel's body in a radially inward direction around the cover in said air gap, wherein said pulsed magnetic force has such a value so that (i) said portion of the vessel's body during its movement towards the cover's welding part attains at the impact a speed value in the inward direction in the range of about 250 m/sec to 500 m/sec and (ii) a contact front line attains at the impact a tangential speed value in the range of about 1000 m/sec to 2500 m/sec, thereby welding said vessel's body and the cover to each other.    
   
   
       2 . The method of  claim 1  comprising expanding the vessel's body at the open end before said placing of the cover within said open end of the vessel's body, thereby providing enhanced holding the cover within the vessel's body.  
   
   
       3 . The method of  claim 1  comprising forming an undulated zone on the vessel's body before said placing of the cover within the open end of the vessel's body, said undulated zone begins at a distance equal to the size of the cover's welding part, thereby providing enhanced holding the cover within the vessel's body.  
   
   
       4 . The method of  claim 1  wherein said cover includes at least one opening suitable for inserting a pipe therein.  
   
   
       5 . The method of  claim 4  comprising: 
 providing a technological plug having at least one pin conforming with said at least one opening; and    inserting the technological plug into said at least one opening of the cover before the energizing of the coil, thereby.    
   
   
       6 . The method of  claim 5  wherein pins are made of a material as hard as the material of the cover.  
   
   
       7 . The method of  claim 5  wherein pins are made of a material harder than the material of the cover.  
   
   
       8 . The method of  claim 7  wherein pins are made of hardened steel.  
   
   
       9 . The method of  claim 1  wherein said vessel's body and said cover are made of the same material.  
   
   
       10 . The method of  claim 1  wherein said vessel's body and said cover are made of different materials.  
   
   
       11 . The method of  claim 1  wherein said vessel's body and said cover are made of a material selected from aluminum, low carbon steel, brass, copper and their alloys.  
   
   
       12 . The method of  claim 1  comprising putting on an insulated cylinder on the vessels body during the energizing said welding induction coil.  
   
   
       13 . A sealed vessel comprising: 
 a vessel's body, where said vessel's body had at least one open end before the vessel was sealed;    a cover having a welding part, where said welding part has a diameter less than the inner diameter of the vessel's body, thereby an air gap was provided between said vessel's body and the welding part of said cover placed within the said at least one open end of the vessel's body before the vessel was sealed,    wherein said cover being welded to the vessel's body by a pulsed magnetic force causing bending a portion of the vessel's body in a radially inward direction around the cover in said air gap, said pulsed magnetic force has such a value so that (i) said portion of the vessel's body during its movement towards the cover's welding part attains at the impact a speed value in the inward direction in the range of about 250 m/sec to 500 m/sec and (ii) a contact front line attains at the impact a tangential speed value in the range of about 1000 m/sec to 2500 m/sec, thereby providing mutual diffusion of atoms of the vessels body and the cover at their impact.    
   
   
       14 . The sealed vessel of  claim 13  wherein said cover further includes a brim part, where a value of a diameter of the cover at the brim part is about the value of an inner diameter of the vessel's body, thereby to provide holding the cover within the vessel's body before the vessel have been sealed.  
   
   
       15 . The sealed vessel of  claim 13  wherein said cover includes at least one opening suitable for inserting a pipe therein.  
   
   
       16 . The sealed vessel of  claim 13  wherein a portion of the vessel's body at the open end is expanded.  
   
   
       17 . The sealed vessel of  claim 13  wherein the vessel's body is undulated at the distance equal to the size of the cover welding part from the open end.  
   
   
       18 . The sealed vessel of  claim 13  wherein said vessel's body and said cover are made of the same material.  
   
   
       19 . The sealed vessel of  claim 13  wherein said vessel's body and said cover are made of different materials.  
   
   
       20 . The sealed vessel of  claim 13  wherein said vessel's body and said cover are made of a material selected from aluminum, low carbon steel, brass, copper and their alloys.  
   
   
       21 . A welding induction coil comprising at least a one-turn coil having two electrodes configured for applying pulsed high voltage thereacross, 
 wherein said welding induction coil is configured for use with an apparatus for sealing a vessel including: 
 a vessel's body having at least one open end, and  
 a cover having a welding part, where said welding part has a diameter less than the inner diameter of the vessel's body, thereby providing an air gap between said vessel's body and the welding part of said cover when the cover is placed within said at least one open end of the vessel's body;  
 wherein said welding induction coil is configured for and operable to generate a pulsed magnetic force causing bending a portion of the vessel's body, placed within a working zone of said welding induction coil, in a radially inward direction around the cover in said air gap, said pulsed magnetic force has such a value so that (i) said portion of the vessel's body during its movement towards the cover's welding part attains at the impact a speed value in the inward direction in the range of about 250 m/sec to 500 m/sec and (ii) a contact front line attains at the impact a tangential speed value in the range of about 1000 m/sec to 2500 m/sec, and thereby to weld said cover to the vessel's body.  
   
   
   
       22 . The welding induction coil of  claim 21  wherein a canal is formed into a body of the coil for providing a passage of cooling liquid therethrough.  
   
   
       23 . The welding induction coil of  claim 22  wherein said liquid is water.  
   
   
       24 . The welding induction coil of  claim 21  wherein said pulsed high voltage is in the range of about 3 kV to 10 kV.  
   
   
       25 . (canceled)