CN-121993096-A - Wellhead cement paste squeezing device and well drilling and cementing construction method

Abstract

The invention belongs to the technical field of well drilling and cementing, and discloses a well head cement paste extruding device, wherein an inner pipe and an outer pipe sleeved inside and outside are arranged on a well head, the well head cement paste extruding device comprises a grouting filling rubber block and a fixed frame, the grouting filling rubber block adopts a split structure, a secondary round platform is formed by splicing left and right, an expandable closed cavity is arranged on the outer wall of the grouting filling rubber block, a grouting channel is vertically inserted into an inner shell of the grouting filling rubber block, the grouting filling rubber block is fixedly arranged on a pipe orifice hoop of the outer pipe by the fixed frame, and the well drilling and cementing construction method is further adopted.

Inventors

• Zhang Zaimin
• ZHENG TAO
• YANG DUO
• ZHONG SHAN
• CHEN JUNSONG
• CHEN ZHIQIANG
• HU MINGJUN
• ZENG DEQIANG
• LIANG HAO
• HUANG YUNTAO
• ZHAI HUIQIONG

Assignees

• 重庆市二零八地质环境研究院有限公司

Dates

Publication Date

20260508

Application Date

20260402

Claims (10)

1. 1. A wellhead cement squeezing device is characterized in that an inner pipe (3) and an outer pipe (4) are arranged on the wellhead, the inner pipe (3) and the outer pipe (4) are sleeved inside and outside the wellhead, the wellhead cement squeezing device comprises a grouting filling rubber block (1) and a fixing frame (2), the grouting filling rubber block (1) adopts a split structure, a secondary round table with a large upper part and a small lower part and a vertically through middle part is formed by splicing left and right, an interface of the round table is placed on a pipe orifice hoop of the outer pipe (4), a bottom vertical end is inserted between the inner pipe (3) and the outer pipe (4), the grouting filling rubber block (1) is provided with an expandable sealing cavity (11) close to the outer wall, the round table is divided into two layers of shells with thin outer part and thick inner part, an inlet (111) is formed at the top of the expandable sealing cavity (11), the grouting filling rubber block (1) can be tightly attached to the contact surface of the inner pipe (3) and the outer pipe (4) through injection medium expansion, a grouting channel (12) is vertically inserted in the inner shell of the grouting filling rubber block (1), the fixing frame (2) adopts a split structure, the left and right splicing frame forms a cylinder frame, the top (2) is sealed up against the pipe orifice hoop (4) to the top of the grouting filling rubber block (1) to form a sealing block (21), and through holes are reserved on the upper baffle plate (21) corresponding to the top end of the grouting channel (12) and the inlet (111).
2. 2. A wellhead cement paste device as claimed in claim 1 and characterised in that the medium injected into the inflatable closed cavity (11) is air or oil.
3. 3. A wellhead cement paste device as claimed in claim 1, wherein the grouting channel (12) is a stainless steel tube.
4. 4. The wellhead cement paste squeezing device according to claim 1, wherein the fixing frame (2) is made of metal.
5. 5. The wellhead cement paste squeezing device according to claim 1, wherein the top closing-in diameter of the combined fixing frame (2) is matched with the outer diameter size of the inner pipe (3), and the bottom closing-in diameter is matched with the outer diameter size of the outer pipe (4).
6. 6. The wellhead cement paste squeezing device according to claim 1, wherein the sum of the height of the horizontal end of the grouting filling rubber block (1) and the height of the pipe orifice joint hoop of the outer pipe (4) is matched with the height dimension in the fixed frame (2).
7. 7. A well drilling and cementing construction method is characterized by comprising the following steps: Step S1, firstly drilling holes corresponding to the well head design position, arranging temporary sleeves, taking the temporary sleeves as outer pipes (4), drilling deeper and smaller holes, and lowering an open sleeve, taking the open sleeve as an inner pipe (3), and then adopting any one of the well head cement paste squeezing devices as claimed in claims 1-6 for installation; S2, injecting a medium from an inlet (111) to expand the grouting filling rubber block (1) to tightly press against the outer wall of the inner pipe (3) and the inner wall of the outer pipe (4), injecting cement slurry from a grouting channel (12) to fill annular gaps between an open sleeve and a temporary sleeve as well as the wall of a drilling hole, and immediately removing a wellhead cement squeezing device before cement slurry is solidified after filling; And S3, taking the first casing as an outer pipe (4), continuously drilling a well corresponding to the first casing, lowering the second casing, taking the second casing as an inner pipe (3), then installing a detached wellhead cement paste squeezing device, and repeating the step S2 to finish the installation of the second casing.
8. 8. The method of well drilling and cementing according to claim 7, wherein in the step S1, a first casing is connected with a plurality of sections of first casing through pipe orifice hoops end to end and is lowered section by section.
9. 9. The method of well drilling and cementing according to claim 7, wherein in the step S3, the two split casings are connected end to end through pipe orifice hoops and lowered section by section.
10. 10. The well drilling and cementing construction method according to claim 7, wherein the top nozzles of the inner pipe (3) and the outer pipe (4) after the installation are higher than the ground.

Description

Wellhead cement paste squeezing device and well drilling and cementing construction method Technical Field The invention belongs to the technical field of well drilling and well cementation, and particularly relates to a well head cement paste squeezing device and a well drilling and well cementation construction method. Background Well cementing is a critical step in the oil and gas drilling process, the purpose of which is to seal the wellbore, support the casing, isolate the different formation pressures and prevent fluid channeling by injecting cement slurry (forming a cement sheath) between the wellbore and the casing. If the annulus cement slurry is not filled, it can pose various serious hazards to the long-term safety and production of the well. At present, cement slurry is directly injected from a first casing or a second casing, the cement slurry is injected, the cement slurry is changed into clear water to replace the cement slurry after reaching a theoretical calculation value, the residual cement slurry in the casing is avoided, and then the cement slurry enters an annular gap between the casing and a well wall from bottom to top from the bottom of the first casing or the second casing, but the method has the following problems that 1) the cement slurry is slower in flow speed under the action of self gravity and is easy to be solidified in a half way to generate hollowness under the action of the self gravity from bottom to top, 2) the cement slurry can flow along the well wall and bottom cracks to cause insufficient filling of the cement slurry to still generate gaps, and 3) when the cement slurry is filled from bottom to top, the top part occupies a certain space due to mixed air to cause the fact that the cement slurry cannot be filled. Disclosure of Invention The invention aims to provide a wellhead cement paste squeezing device and a well drilling and cementing construction method, which are used for filling annular cement paste, improving the safety of a well and solving the problems that the annular gap is filled by directly injecting cement paste from a sleeve and then spreading the cement paste from the bottom of the sleeve, the flow speed is slow, half-way solidification is easy, the cement paste flows away from cracks and is not filled with air, and the annular gap cannot be filled. The wellhead cement paste extruding device comprises a grouting filling rubber block and a fixed frame, wherein the grouting filling rubber block adopts a split structure, a secondary round table with a large upper part and a small lower part and vertically penetrating through the middle is formed by splicing left and right, the interface of the round table is placed on an outer pipe orifice hoop, the vertical end of the bottom is inserted between the inner pipe and the outer pipe, an expandable closed cavity is arranged on the outer wall of the grouting filling rubber block, the round table is divided into two layers of shells with thin outer part and thick inner part, the top of the expandable closed cavity is provided with an inlet, the grouting filling rubber block can be closely attached to the contact surface of the inner pipe and the outer pipe through expansion of injection media, a grouting channel is vertically inserted in the inner shell of the grouting filling rubber block, the fixed frame adopts a split structure, a cylindrical frame is formed by splicing left and right, the top of the fixed frame is closed inwards to form an upper baffle on the top of the grouting filling rubber block, the bottom is closed inwards to form a lower baffle on the outer pipe orifice hoop, and accordingly the grouting filling rubber block is fixedly arranged on the outer pipe hoop, and the top of the grouting filling rubber block is arranged on the upper pipe orifice hoop corresponding to the upper baffle and the top of the grouting channel is reserved. As the scheme is preferable, the medium injected into the inflatable closed cavity adopts air or oil, so that the manufacturing cost is low, and the materials are reasonable. Further preferably, the grouting channel is made of stainless steel pipes, the materials are selected reasonably, and the grouting channel is prevented from being influenced by expansion of the expandable closed cavity. Further preferably, the fixing frame is made of metal, the material selection is reasonable, and the structure is stable. Further preferably, the top closing-in diameter of the combined fixing frame is matched with the outer diameter of the inner pipe, the bottom closing-in diameter is matched with the outer diameter of the outer pipe, and the combined fixing frame is reasonable in design, so that the installation of the wellhead cement paste squeezing device is not affected. And more preferably, the sum of the height of the horizontal end of the grouting filling rubber block and the height of the pipe orifice joint hoop of the outer pipe is matched with the height in the fix