CN-121719489-B - Petroleum drilling casing head

CN121719489BCN 121719489 BCN121719489 BCN 121719489BCN-121719489-B

Abstract

The invention relates to the technical field of casing heads, in particular to an oil drilling casing head, which comprises a casing head body and a wellhead pipeline connected with the casing head body, wherein an external locking assembly is arranged on the wellhead pipeline, an internal locking assembly is arranged in the casing head body, and the casing head body and the wellhead pipeline are quickly locked and fixed through the external locking assembly and the internal locking assembly. According to the invention, the functions of quick locking and dynamic unlocking without bolts are realized through the arrangement of the internal locking assembly, the internal locking assembly adopts a staged locking design, when a wellhead pipeline is inserted into a casing head body, the internal locking assembly firstly enters an axial limiting stage, after the pipeline is completely positioned, the system is automatically switched to a longitudinal locking stage, and a plurality of groups of second wedge blocks which are symmetrically arranged are expanded in the radial direction under the downward movement action of the first wedge blocks, so that the second wedge blocks are inserted into the vertical sections of the locking grooves, and the insertion and fixation are realized.

Inventors

TANG MINGXING
LI JINGTAO
LI XIAOBO
ZHANG JUNXIA
YANG YANG
SUN FEI
YAO ZHENQING
CAO YANG

Assignees

江苏卫东机械有限公司

Dates

Publication Date: 20260508
Application Date: 20260225

Claims (8)

1. The petroleum drilling casing head comprises a casing head body (1) and a wellhead pipeline (2) connected with the casing head body (1), and is characterized in that an external locking assembly (3) is arranged on the wellhead pipeline (2), an internal locking assembly (4) is arranged in the casing head body (1), and the casing head body (1) and the wellhead pipeline (2) are quickly locked and fixed by the interaction of the external locking assembly (3) and the internal locking assembly (4); The casing head is characterized in that a diameter reducing section is arranged inside the casing head body (1), an inclined surface (12) is formed on the diameter reducing section, a limit groove (13) is formed in the upper surface of the inclined surface (12), an L-shaped groove (14) is formed in the inner bottom plate of the limit groove (13), and the bottom end of the wellhead pipeline (2) is provided with the diameter reducing section matched with the casing head body (1); The inner locking assembly (4) comprises locking blocks (41) arranged on the outer wall of the reducing section of the wellhead pipeline (2), a driving block (42) is arranged at the bottom end of each locking block (41), a limiting ring (43) is rotatably arranged at the bottom end of the wellhead pipeline (2), a plurality of locking grooves (44) are formed in the outer wall of each limiting ring (43), the locking grooves (44) are distributed in an annular equidistant mode and are of an inverted L-shaped structure, and spiral blades (45) are arranged on the inner wall of each limiting ring (43); a first wedge-shaped block (46) is movably arranged in the vertical section of the L-shaped groove (14), and a second wedge-shaped block (49) is movably arranged in the horizontal section of the L-shaped groove (14); The lower surface welding of second wedge (49) has second slider (410), and horizontal spout sliding connection that sets up on second slider (410) and L shape groove (14) inner wall, the lower surface welding of second slider (410) has second spring (411), and second spring (411) are the extension spring, and in the initial state, under the pulling force effect of second spring (411), promote second slider (410) and remove the middle part of horizontal spout for second wedge (49) with locking groove (44) separation.
2. The oil drilling casing head according to claim 1, wherein a lower fixing disc (11) is arranged on the outer wall of the casing head body (1), an upper fixing disc (21) is arranged on the outer wall of the wellhead pipeline (2), when the bottom end of the wellhead pipeline (2) is inserted into the casing head body (1) for connection, the upper fixing disc (21) and the lower fixing disc (11) are mutually matched in a fit mode, and an O-shaped sealing ring is arranged on the joint surface of the upper fixing disc (21) and the lower fixing disc (11).
3. The petroleum drilling casing head according to claim 1, wherein a first sliding block (47) is welded on the outer wall of the first wedge block (46), the first sliding block (47) is slidably connected with a vertical sliding groove formed in the inner wall of the L-shaped groove (14), and a first spring (48) is welded on the outer wall of the first sliding block (47).
4. The oil drilling casing head according to claim 1, wherein a plurality of arc-shaped sliding blocks (431) are welded at the top of the limiting ring (43), an arc-shaped sliding groove (433) matched with the arc-shaped sliding blocks (431) is formed in the lower surface of the wellhead pipeline (2), the arc-shaped sliding blocks (431) are in sliding connection with the arc-shaped sliding grooves (433), and an arc-shaped spring (432) is welded on one side wall of the arc-shaped sliding blocks (431).
5. An oil drilling casing head according to claim 2, characterized in that the external locking assembly (3) comprises a plurality of clamping seats (31) and connecting rods (39) circumferentially distributed around the outer side of the upper fixed disc (21), the clamping seats (31) are of concave structures, sliding seats (32) are welded on the clamping seats (31), strip-shaped sliding grooves (33) are formed in the upper fixed disc (21), the sliding seats (32) are in sliding connection with the strip-shaped sliding grooves (33), a rotating seat (34) is sleeved on the wellhead pipeline (2), one end of each connecting rod (39) is rotatably connected to the corresponding rotating seat (34), and the other end of each connecting rod (39) is rotatably connected with the corresponding clamping seat (31).
6. The oil drilling casing head according to claim 5, further comprising a driving mechanism, wherein the driving mechanism comprises a fixed ring (36), the fixed ring (36) is welded and fixed on the wellhead pipeline (2), a driving nut (35) is connected to the wellhead pipeline (2) above the fixed ring (36) in a threaded manner, a driving rod (38) is welded at the bottom end of the driving nut (35), and the bottom end of the driving rod (38) is fixedly connected with the rotating seat (34).
7. The petroleum drilling casing head according to claim 6, wherein a plurality of driving rods (38) are arranged, the driving rods (38) are circumferentially distributed around the outer side of the wellhead pipeline (2) at equal intervals, and the fixing ring (36) is provided with arc-shaped through holes (37) matched with the driving rods (38).
8. An oil drilling casing head according to claim 2, wherein the outer diameter of the lower fixed disc (11) is smaller than the outer diameter of the upper fixed disc (21).

Description

Petroleum drilling casing head Technical Field The invention relates to the technical field of casing heads, in particular to an oil drilling casing head. Background The well casing head is an important connecting piece between the casing and the wellhead device, is a device used for connecting among all layers of casings, between the casing and the blowout preventer and between the well casing and the oil extraction wellhead after well completion, is a core component of an oil and gas well wellhead system and has the triple functions of connection, bearing and sealing. The Chinese patent application with the publication number of CN118933641A discloses an opposite-plug installation type casing head for petroleum drilling, which comprises a casing head main body and a calibration sealing assembly, wherein the matched calibration sealing assembly is arranged between the casing head and a wellhead and between the casing head and a butt joint pipe body so as to ensure that when bolts are used for fixing, the installation jacks on the connecting disc body can be aligned, namely the connection fixing convenience of a first installation bolt is improved, and further the overall installation construction efficiency is positively influenced. As in the above application, the drilling casing head is used as a transition structure between the casing string and the wellhead device, and in the prior art, the connection with devices such as a blowout preventer, a christmas tree, a wellhead pipeline and the like is realized mostly through a standardized flange, and the drilling casing head is connected through a flange nut, so that the installation efficiency is low, and frequent disassembly or down-hole impact load may cause abrasion of threads of the nut, a bolt or a flange plate, so that the connection reliability is reduced. Disclosure of Invention In order to solve the problems, the invention provides an oil drilling casing head. The invention adopts the following technical scheme that the petroleum drilling casing head comprises a casing head body and a wellhead pipeline connected with the casing head body, wherein an external locking assembly is arranged on the wellhead pipeline, an internal locking assembly is arranged in the casing head body, and the casing head body and the wellhead pipeline are quickly locked and fixed by mutually matching the external locking assembly and the internal locking assembly. As the further description of the technical scheme, a lower fixing disc is arranged on the outer wall of the casing head body, an upper fixing disc is arranged on the outer wall of the wellhead pipeline, when the bottom end of the wellhead pipeline is inserted into the casing head body for connection, the upper fixing disc is arranged on the lower fixing disc in a laminating mode, and an O-shaped sealing ring is arranged on the joint surface of the upper fixing disc and the lower fixing disc. As further description of the technical scheme, the inside of the casing head body is provided with a diameter reducing section, an inclined surface is formed on the diameter reducing section, a limit groove is formed on the upper surface of the inclined surface, an L-shaped groove is formed on the inner bottom plate of the limit groove, and the bottom end of the wellhead pipeline is provided with the diameter reducing section matched with the casing head body for use; The inner locking assembly comprises a locking block arranged on the outer wall of the reducing section of the wellhead pipeline, a driving block is arranged at the bottom end of the locking block, a limiting ring is rotatably arranged at the bottom end of the wellhead pipeline, a plurality of locking grooves are formed in the outer wall of the limiting ring, the locking grooves are distributed in an annular equidistant manner and are of an inverted L-shaped structure, and spiral blades are arranged on the inner wall of the limiting ring; the vertical section of L-shaped groove is interior the activity is provided with first wedge, the horizontal section of L-shaped groove is interior the activity is provided with the second wedge. As further description of the technical scheme, the outer wall of the first wedge-shaped block is welded with the first sliding block, the first sliding block is in sliding connection with the vertical sliding groove formed in the inner wall of the L-shaped groove, the outer wall of the first sliding block is welded with the first spring, and in an initial state, the first sliding block is pushed to move at the bottom end of the vertical sliding groove under the action of the elastic force of the first spring. As further description of the technical scheme, the lower surface of the second wedge block is welded with a second sliding block, the second sliding block is in sliding connection with a horizontal sliding groove formed in the inner wall of the L-shaped groove, the lower surface of the second sliding block is welded with a s