Unlimited Downhole Fracture Zone System

Abstract

Apparatus and method are provided for diverting treatment fluids in wells. Sliding sleeves or valves are sequentially opened by dropping balls that may be of uniform size. Opening of one valve moves a collet into position such that the same size ball can be used to open a second valve. Any selected number of valves can be opened with the same size balls. Systems using the valves are also disclosed, along with methods for operating.

1 . A diverter valve for releasing fluid from a tubular string located within a well to a selected zone or segments of formations to be treated comprising:
 a housing having upper and lower connections and having a flow-through fluid passageway;   a collet having a plurality of flexible fingers positioned within the flow-through fluid passageway and axially moveable therein;   at least one outlet formed in the periphery of the housing;   a valve sleeve positioned within the flow-through fluid passageway and axially moveable therein, said valve sleeve having at least one outlet port; and   a connector sleeve slidably receiving an upper end of the collet and a lower end of the valve sleeve.   
     
     
         2 . The valve of  claim 1  further including:
 a chamber positioned between the housing and collet; 
 a hydraulic logic piston slidably mounted on the collet in the chamber; and 
 an outlet passageway between the chamber and the exterior surface of the housing. 
 
     
     
         3 . The valve of  claim 1  wherein the flow through fluid passageway includes a first beveled surface and a second beveled surface downstream of the first beveled surface. 
     
     
         4 . The valve as claimed in  claim 2  wherein the hydraulic logic piston is connected to the collet by shear pins. 
     
     
         5 . The diverter valve of  claim 1  further including a spring in the housing resisting axial movement of the collet and valve sleeve. 
     
     
         6 . The diverter valve of  claim 3  further including an annular chamber located between an upper portion of the valve sleeve and the valve body and an outlet vent communicating with the annular chamber. 
     
     
         7 . The diverter valve of  claim 1  further including first and second shoulders located on the valve sleeve and a plurality of ports in the circumference of the valve sleeve between the first and second shoulders. 
     
     
         8 . The diverter valve of  claim 1  further including a plurality of shear pins extending between the collet and valve sleeve, a snap ring carried by the valve sleeve and a snap ring recess in the flow through passageway of the valve body. 
     
     
         9 . The diverter sleeve of  claim 1  wherein the connector sleeve is of the lost motion type whereby one of the valve sleeve and collet can move axially with respect to each other. 
     
     
         10 . Apparatus for fracturing a plurality of selected zones or segments of formations extending outwardly from an oil or gas well comprising:
 a tubular string;   at least one packer mounted on the tubular string; and   a plurality of diverter valves according to  claim 1  connected in the tubular string.   
     
     
         11 . Apparatus according to  claim 10  further including a plurality of balls of similar diameter. 
     
     
         12 . A lower initiation tool for use in apparatus for hydraulic fracturing comprising:
 a valve housing having upper and lower connection portions for connecting the tool to a tubular;   a flow-through fluid passageway;   a valve sleeve positioned within the flow-through passageway having at least one side outlet port and a ball valve seat;   at least one outlet provided on the wall of the housing adapted to align with the outlet port in the valve sleeve when the valve sleeve moves a selected distance within the valve housing;   an annular chamber formed between the valve sleeve and the valve housing; and   a fluid passageway in the valve housing connectable to a jumper conduit at one end and extending to an interior surface of the flow through passageway.   
     
     
         13 . A lower initiation tool according to  claim 12  further including shear pins extending between the valve housing and valve sleeve,
 a snap ring carried by the valve sleeve, and 
 a snap ring recess on an interior surface of the valve housing. 
 
     
     
         14 . A method for treating selected zones or segments of formations extending outwardly from an oil or gas well comprising:
 positioning a tubular string within a bore of the well, said tubular string comprising tubulars, at least one packer on the tubulars, and a plurality diverter valves according to  claim 1 ,   initiating a flow of treating fluid within the tubular string;   diverting the treating fluid flow at the last diverter valve to the zone or segment to be treated by dropping a ball of a selected size into the tubular string;   causing the next upstream diverter valve to be placed in a set position; and   dropping a second ball of the same diameter into the tubular string to terminate treating of the first zone or segment and simultaneously diverting treating fluid from the next diverter valve into the next zone or segment to be treated.   
     
     
         15 . The method according to  claim 14  further including terminating the flow of treating fluid and recovering the balls from the tubular string. 
     
     
         16 . A method of treating selected zones or segments of formations extending outwardly from an oil or gas well comprising:
 isolating a plurality of zones or segments;   directing treating fluid into the well;   injecting treating fluid into a first one of the zones or segments to be treated;   terminating the flow of treating fluid to the first one of the zones or segments and concurrently diverting the flow of treating fluid into a second zone or segment to be treated by introducing a ball of a selected size; and   terminating the flow of treating fluid to the second zone or segment while concurrently diverting the flow of treating fluid to a third zone or segment by introducing a second ball of the same size as the first ball into the tubular string.   
     
     
         17 . A diverter valve for releasing fluid from a tubular string located within a well to a selected zone or segments of formations to be treated comprising:
 a housing having upper and lower connections and having a flow-through fluid passageway;   the flow-through fluid passageway having a variable size diameter portion;   at least one outlet formed in the periphery of the housing; and   a valve sleeve positioned within the flow-through fluid passageway and axially moveable therein in response to a change in diameter of the flow-through fluid passageway, said valve sleeve having at least one outlet port.   
     
     
         18 . A diverter valve according to  claim 17  wherein the variable size diameter portion of the flow-through fluid passageway comprises a collet having a plurality of flexible fingers at one end thereof and axially movable within the flow-through fluid passageway. 
     
     
         19 . A diverter valve as claimed in  claim 18  and further comprising a connector sleeve slidably receiving an upper end of the collet and a lower end of the valve sleeve. 
     
     
         20 . A diverter valve as claimed in  claim 18  wherein the flow-through fluid passageway includes first and second frustoconical portions, a downstream portion of the second frustoconical portion being of less diameter than a downstream portion of the first frustoconical portion.