Stage cementing tool

Abstract

A stage cementing tool for use in cementing a casing in the well is disclosed. The stage cementing tool includes a housing with a mechanically set packer to seal against the well. A hydraulically actuated opening sleeve will move in the housing to uncover flow ports in the housing, and allow flow therethrough into the well.

1 . A cementing tool for use in a well comprising:
 a housing defining a longitudinal flow passage therethrough, and having at least one flow port disposed in a wall thereof;   a mechanically set packer connected to the housing for sealing against a well; and   a hydraulically actuated opening sleeve disposed in the housing, the opening sleeve being movable from a closed position covering the at least one flow port to an open position wherein the at least one flow port is uncovered and communicates the longitudinal flow passage with the well.   
   
   
       2 . The cementing tool of  claim 1 , the mechanically set packer comprising:
 a packer sub connected to the housing;   a radially expandable packer element supported by the packer sub and disposed about the housing; and   a packer ring slidable on the housing and positioned so that movement of the packer ring in a first direction will cause the packer element to move to a set position wherein the packer element sealingly engages the well.   
   
   
       3 . The tool of  claim 2  further comprising a packer setting sleeve disposed in the housing and connected to the movable packer ring, wherein movement of the setting sleeve in the first direction moves the packer ring in the first direction. 
   
   
       4 . The tool of  claim 3 , the housing having packer setting slots in the wall thereof, the setting sleeve being connected to the packer ring with connectors extending through the packer setting slots and movable therein. 
   
   
       5 . The tool of  claim 4  wherein the packer setting sleeve completely covers the setting packer slots in the set and unset positions of the packer. 
   
   
       6 . The tool of  claim 3  wherein the packer setting sleeve includes a seat for receiving a setting plug and wherein the setting sleeve will move the packer ring to expand the packer element to the set position when the setting plug is engaged with the seat and pressure in the longitudinal flow passage is increased. 
   
   
       7 . The cementing tool of  claim 1 , wherein the hydraulic setting sleeve has an upper portion with a first outer diameter and a lower portion with a second outer diameter smaller in magnitude than the first outer diameter. 
   
   
       8 . The cementing tool of  claim 7 , further comprising a closing sleeve disposed about the housing and detachably connected thereto for covering the flow ports after the opening sleeve has moved to the open position and cement has been flowed through the flow ports. 
   
   
       9 . A cementing tool for use in a well comprising:
 a housing defining a flow passage;   a packer element disposed about the housing and movable from an unset to a set position wherein the packer element engages the well;   a hydraulically actuated opening sleeve movable from a closed to an open position, wherein in the open position the opening sleeve uncovers circulating ports in the housing for communicating cement from the flow passage into the well.   
   
   
       10 . The cementing tool of  claim 9  further comprising a closing sleeve disposed about the housing and positioned above the opening sleeve for covering the circulating ports after cement has been communicated therethrough. 
   
   
       11 . The cementing tool of  claim 10 , further comprising an operating sleeve detachably connected in the housing, the closing sleeve being connected to and movable with the operating sleeve. 
   
   
       12 . The cementing tool of  claim 11  further comprising a packer setting sleeve disposed in the housing, wherein the packer setting sleeve is adapted to move the packer element to the set position. 
   
   
       13 . The cementing tool of  claim 12  wherein a first plug is displaced into the tool to move the packer setting sleeve and a second plug is displaced in the tool to move the operating sleeve. 
   
   
       14 . The cementing tool of  claim 9  the hydraulically actuated opening sleeve comprising an upper portion having a first outer diameter, and a lower portion with a second, smaller diameter, wherein the opening sleeve is detachably connected to the housing in the closed position in which the opening sleeve prevents communication through the circulating ports. 
   
   
       15 . A cementing tool for use in a wellbore comprising:
 a housing, the housing and the wellbore defining an annulus therebetween;   a packer element disposed about the housing for engaging the wellbore;   a packer setting sleeve for expanding the packer element to engage the wellbore;   an opening sleeve movable relative to the housing and the packer setting sleeve, wherein in a closed position the opening sleeve blocks communication into the annulus and in the open position permits flow into the annulus through circulation ports in the housing.   
   
   
       16 . The cementing tool of  claim 15  wherein the opening sleeve is disposed in the housing and movable solely upon the application of hydraulic pressure in the housing. 
   
   
       17 . The cementing tool of  claim 15 , further comprising a packer end ring at the upper end of the packer element wherein the packer setting sleeve is connected to the packer end ring. 
   
   
       18 . The cementing tool of  claim 17 , wherein the housing has slots defined therein, and where connectors extend through the slots to connect the packer setting sleeve to the packer end ring, the packer setting sleeve completely covering the slots.