Travelling disc valve apparatus

Abstract

A travelling disc valve assembly, comprising a length of tubing lowered down a cased wellbore; a crossover tool secured to the lower end of the length of tubing; a length of wash pipe secured to the lower end of the crossover tool; a disc valve assembly secured to the wash pipe and positioned to a lower circulation position in the well bore; a disc valve secured in a bore of the assembly; in the upper, portion of the assembly for shearing off the connection between the wash pipe and the disc valve assembly, when the disc valve assembly is in an upper position, providing to prevent fluid from flowing into the formation below the disc valve and to prevent production flow to the surface; and a to rupture the disc valve at a predetermined time so that the production within the formation is allowed to flow through the assembly bore to the surface.

What is claimed as the invention is: 
     
       1. A travelling disc valve assembly, comprising: a) a length of tubing lowered down a cased wellbore;   b) a crossover tool secured to the lower end of the length of tubing;   c) a disc valve assembly secured to the crossover tool and positioned to a lower circulation position in the well bore, said assembly further comprising a disc valve secured in a bore of the assembly;   d) means interconnecting the crossover tool with the disc valve assembly;   e) means in the upper portion of the disc valve assembly for disconnecting the disc valve assembly, from the crossover tool when the disc valve assembly is an upper position, providing means to prevent fluid from flowing into the formation below the disc valve and to prevent production flow to the surface; and   f) means to rupture the disc valve so that the production within the formation is allowed to flow through the assembly bore to the surface.   
     
     
       2. The disc valve assembly in claim 1, wherein the assembly is positioned below the packer extension in the well bore. 
     
     
       3. The disc valve assembly in claim 1, wherein there is further provided a telltale screen for allowing initial circulation of gravel pack slurry. 
     
     
       4. The disc valve assembly in claim 1, wherein there is further provided a production screen for allowing production to flow into the assembly during recovery of hydrocarbons from the formation. 
     
     
       5. The disc valve assembly in claim 1, wherein the crossover tool and the wash pipe are raised until a top seal ring is retrieved from a bottom seal bore to permit circulation through the production screen. 
     
     
       6. The disc valve assembly in claim 1, wherein the means for shearing the crossover tool from the disc valve assembly further comprises a shear joint above a collet, wherein shear screws in the shear joint shear maintaining the disc valve assembly locked in position so that the disc valve may seal against upward or downward flow in the bore of the assembly. 
     
     
       7. A valve assembly positionable in a wellbore to prevent flow of fluids above or below the position of the valve, comprising: a) an assembly means positioned without a cased borehole, extending from a length of wash pipe, the assembly means having a continuous bore therethrough;   b) substantially circular, rupturable valving member secured within the bore of the assembly means, and lowered to a first position adjacent a telltale screen;   c) a crossover tool and wash pipe positioned between the lower end of the tubing string and the assembly means;   d) means for moving the assembly means to a second position until ports in the crossover tool are positioned above a packer, so that sand slurry may be circulated back to the well surface;   e) a joint positioned between the wash pipe and the assembly means, for defining a means to disconnect the connection between the wash pipe and the assembly means, when the wash pipe is raised so that the assembly means, together with the disc valveing member is secured in place with the bottom seal rings and the disc valve member further defining a barrier for preventing fluid flow into the formation below the valve member and for preventing hydrocarbon flow from the formation to a point above the valving member; and   f) means, after the valving member is in position, to rupture the valving member for allowing the hydrocarbon flow from the formation to flow up to the surface during production.   
     
     
       8. The valve assembly in claim 7, wherein the valving member is preferably a glass disc. 
     
     
       9. The valve assembly in claim 7, wherein there is further comprises bottom seal rings and top seal rings for sealing against fluid flow during the operation of the assembly. 
     
     
       10. The valve assembly in claim 9, wherein the bottom seal rings against in sealing against fluid flow after the valve assembly has been sheared from the crossover tool. 
     
     
       11. The valve assembly in claim 7, wherein the crossover tool and wash pipe are withdrawn from the wellbore after the valve assembly has been sheared therefrom. 
     
     
       12. The valve assembly in claim 7, wherein the means to rupture the valving member is a tool lowered into the hole. 
     
     
       13. The valve assembly in claim 7, wherein the means to rupture the valve member is fluid pressure. 
     
     
       14. The valve assembly in claim 7, wherein the joint to disconnect the assembly means comprises a shear joint. 
     
     
       15. A travelling disc valve assembly, comprising: a) a continuous casing within a wellbore, the, casing having a plurality of perforations in the wall for allowing formation flow thereinto;   b) a tubing string lowered into the casing, including a packer assembly and at least having a production screen and a telltale screen along its length;   c) a travelling disc valve assembly positioned within the production casing, further comprising: i) an upper length of wash pipe;   ii) a crossover tool engaged to an upper end of the length of wash pipe;   iii) a travelling disc valve assembly, including a rupturable disc valve locked in the assembly bore, top and bottom seal rings, and a shear joint between the disc valve assembly and the wash pipe;     d) means for positioning the disc valve at the position of the telltale screen for allowing circulation through the assembly bore to the surface;   e) means for positioning the disc valve at a second position between the production screen and the telltale screen for allowing fluid flow through the production screen;   f) means for disconnecting the disc valve assembly from the wash pipe after the disc valve has been moved to a position above the production screen and locking the valve in place; and   g) means for rupturing the disc valve to allow fluid to flow from the formation through the production screen and up to the surface through the bore in the assembly; .Iadd.   
     
     
       16.  A traveling valve assembly, comprising: a) a length of tubing lowered down a cased wellbore;   b) a crossover tool secured to the lower end of the length of tubing;   c) valving means secured to the crossover tool and positioned to a lower circulation position in the well bore;   d) means interconnecting the crossover tool with the valving means; and   e) means in the upper portion of the valving means for disconnecting the valving means from the crossover tool when the valving means is an upper position, providing means to prevent fluid from flowing into the formation below the valving means and to prevent production flow to the surface. .Iaddend. .Iadd.17. The valve assembly in claim 16, further comprising means to open the valving means so that the production within the formation is allowed to flow through the valving means to the surface. .Iaddend. .Iadd.18. The valve assembly in claim 16 wherein the valving means is a rupturable disc valve member. .Iaddend. .Iadd.19. A valve assembly, comprising:   a) a length of tubing lowered down a cased wellbore;   b) a crossover tool secured to the lower end of the length of tubing;   c) a valving assembly secured to the crossover tool and positioned to a lower circulation position in the well bore and including a bore through the assembly;   d) means interconnecting the crossover tool with the valving assembly;   e) means in the upper portion of the valving assembly for disconnecting the valving assembly from the crossover tool when the valving assembly is an upper position, further providing means to prevent fluid from flowing into the formation below the valving assembly and to prevent production flow to the surface; and   f) means to open a valve in the valving assembly so that the production within the formation is allowed to flow through the valving assembly to the surface. .Iaddend. .Iadd.20. The valve assembly in claim 19, wherein the valving means is a rupturable disc valve member.