A casing head device with multiple structures

Abstract

The invention relates to a multi-structure casing head device, comprising: a lifting chassis, a casing head shell, a grease injection valve, a BT sealing ring, a threaded flange, a metal sealing ring, an "O"-shaped sealing ring, a mandrel hanger, a pointed top screw, an extended single male short joint, a flat top screw, a pressure gauge assembly, an instrument flange, a flat gate valve, a pressure relief valve, a slip hanger, a rectangular sealing ring, an inverted slip device, and bolts; the characteristic is that: a taper sealing surface is processed inside the casing head shell, a top screw groove is added to the upper end flange, a taper sealing internal thread and a BT sealing ring groove are processed in sequence on the inner side of the lower end, the grease injection valve and the pressure relief valve are respectively installed on the periphery of the BT sealing ring groove, the BT sealing ring groove is placed in the BT sealing ring groove, the surface casing is connected to the taper sealing internal thread of the casing head shell, and the lifting chassis is welded to the lower end of the casing head shell; flow channel holes are processed on both sides of the casing head shell, one side is connected to the threaded flange, and the other side is connected to the flat gate valve, the instrument flange, and the pressure gauge assembly in sequence.

Description

Technical Field

[0001] The invention belongs to the field of petroleum machinery, and in particular relates to a casing head device with multiple structures. Background Art

[0002] At present, in the actual production process of oil fields, the casing and the mandrel type casing head are connected by a tapered sealing thread. However, when the casing taper sealing thread is damaged and cannot be sealed, or the surface casing is not lowered to the predetermined position at the well site, the slip type casing head can only be replaced, using slips and hanging casing; thus, a variety of casing heads need to be spared on site, which increases the cost of the operating unit, prolongs the operation time, delays the construction period, and has the disadvantages of cumbersome disassembly and replacement, which are problems that production and use units need to solve together. Summary of the invention

[0003] The present invention provides a casing head device with multiple structures in order to solve the technical problems of the existing casing head having a single connection structure, high production cost, long operation time, and complicated disassembly and replacement.

[0004] In order to achieve the above object, the present invention is implemented by the following technical solutions:

[0005] A multi-structure casing head device comprises: a lifting chassis, a casing head shell, a grease injection valve, a BT sealing ring, a threaded flange, a metal sealing ring, an "O" type sealing ring, a mandrel hanger, a pointed top screw, an extended single male short joint, a flat top screw, a pressure gauge assembly, an instrument flange, a flat gate valve, a pressure relief valve, a slip hanger, a rectangular sealing ring, an inverted slip device, and bolts; characterized in that: a tapered sealing surface is processed inside the casing head shell, a top screw groove is added to the upper end flange, and a tapered sealing internal thread and a BT sealing ring groove are processed in sequence on the inner side of the lower end; the grease injection valve and the pressure relief valve are respectively installed on the periphery of the BT sealing ring groove, the BT sealing ring groove is placed in the BT sealing ring groove, the surface casing is connected to the tapered sealing internal thread of the casing head shell, and the lifting chassis is welded to the lower end of the casing head shell for adjusting the level and height of the casing head; flow channel holes are processed on both sides of the casing head shell, one side is connected to the threaded flange, and the other side is connected to the flat gate valve, the instrument flange, and the pressure gauge assembly in sequence for observing the changes in the internal pressure of the casing head.

[0006] As a further improvement of the present invention, two internal threads and a gasket groove are designed on the upper end of the core shaft hanger. The upper thread is processed with a reverse trapezoidal internal thread to facilitate the lifting of the tool. The lower thread is processed with a tapered sealing internal thread to connect the extended single male short section. The metal gasket installed in the gasket groove is used to connect the seal of the high-pressure wellhead device. The lower end of the core shaft hanger is designed as an integrated unit with the double male short section, and the lower end is processed with a tapered sealing external thread to connect with the oil layer casing.

[0007] As a further improvement of the present invention, the core shaft hanger is placed inside the casing head shell, and a double sealing form of a metal sealing ring and an "O"-ring is adopted between them. The metal seal deforms and expands under the deadweight of the hanging casing to achieve a sealing effect.

[0008] As a further improvement of the present invention, the pointed top screw and the flat head top screw are tightened in the top screw groove under the action of external force, the upper end of the core shaft hanger is processed with a 45° chamfer, and the pointed top screw is tightened so that the pointed corner of the pointed top screw is pressed tightly against the outer chamfer of the upper end of the casing hanger, which can prevent the casing hanger from moving up and down longitudinally. A stop groove is designed on the periphery of the core shaft hanger, and the flat head top screw is tightened so that the flat head of the flat head top screw is pressed tightly against the stop groove of the casing hanger, which prevents the casing hanger from moving laterally left and right.

[0009] As a further improvement of the present invention, when the tapered sealing thread of the casing is damaged, or the surface casing is not installed in place, a cava hanger and an inverted cava device can be used. The cava hanger is placed inside the casing head shell and sealed with a rectangular rubber ring. The pointed top screw is tightened to press the cava hanger to expand the rectangular rubber ring to achieve a sealing effect. The oil layer casing passes through the cava hanger, and the cava teeth are in close contact with the oil layer casing. Under the weight of the oil layer casing, the cava teeth are stimulated to clamp the casing to complete the function of hanging the oil layer casing.

[0010] As a further improvement of the present invention, the inverted cava device is connected to the lower part of the casing head shell with bolts, the surface casing passes through the inverted cava device and the BT sealing ring, the cava teeth are in close contact with the surface casing, and the connecting bolts are tightened to cause the cava teeth to bite the surface casing to achieve the purpose of hanging the surface casing. Sealing grease is injected into the BT sealing groove in the casing head shell through the grease injection valve, so that the BT sealing ring hugs the outer wall of the casing to form a sealing structure.

[0011] The advantages of the present invention are that the inside of the casing head shell can use the threaded connection casing of the core shaft hanger or the casing can be hung by a slip type hanger. The bottom of the casing head shell can also be directly connected to the casing with a thread, or the casing can be hung by an inverted slip device. In emergency situations, it can meet the various connection methods of the on-site casing of the oil field, so that the casing head shell can be reused, reducing production and maintenance costs, avoiding safety hazards, saving energy, simplifying on-site construction and installation, shortening working time, and improving work efficiency. In short, the multi-structure casing head device is novel in design and reasonable in structure, and plays a positive role in the safe production, increased production, and stable production of the oil field. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Attached Figure 1 The figure is an overall schematic diagram of installing the mandrel hanger of the present invention.

[0013] Attached Figure 2 The present invention is an overall schematic diagram of installing a slip hanger and an inverted slip device.

[0014] Attached Figure 3 Schematic diagram of the structure of the mandrel tube hanger.

[0015] Attached Figure 4 Schematic diagram of the structure of the slip tube hanger.

[0016] Attached Figure 5 It is a schematic diagram of the structure of the inverted slip device.

[0017] Attached Figure 1 and attached Figure 2 The utility model comprises: a lifting base frame 1, a casing head housing 2, a grease injection valve 3, a BT sealing ring 4, a threaded flange 5, a metal sealing ring 6, an "O" type sealing ring 7, a core shaft hanger 8, a pointed top screw 9, an extended single male short joint 10, a flat head top screw 11, a pressure gauge assembly 12, an instrument flange 13, a flat gate valve 14, a pressure relief valve 15, a slip hanger 16, a rectangular sealing ring 17, an inverted slip device 18, and a bolt 19. DETAILED DESCRIPTION

[0018] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

[0019] A tapered sealing surface is machined inside the casing head shell 2, a top thread groove is added to the upper flange, and a tapered sealing internal thread and a BT sealing ring groove are machined on the inner side of the lower end in sequence. The grease injection valve 3 and the pressure relief valve 15 are respectively installed on the periphery of the BT sealing ring groove, and the BT sealing ring groove 4 is placed in the BT sealing ring groove. The surface casing is connected to the tapered sealing internal thread of the casing head shell 2, and the lifting base 1 is welded to the lower end of the casing head shell to adjust the level and height of the casing head; flow channel holes are machined on both sides of the casing head shell 2, one side is connected to the threaded flange 5, and the other side is connected to the flat gate valve 14, the instrument flange 13, and the pressure gauge assembly 12 in sequence to observe the changes in the internal pressure of the casing head; two holes are designed on the upper end of the core shaft hanger 8 The upper thread is processed with a reverse trapezoidal internal thread, which is convenient for picking up and lifting tools, and the lower thread is processed with a tapered sealing internal thread, which is connected to the extended single male short section 10. The metal gasket installed in the gasket groove is used to connect the seal of the high-pressure wellhead device. The lower end of the mandrel hanger 8 adopts an integrated design with the double male short section, and the lower end is processed with a tapered sealing external thread to connect the oil layer casing; the mandrel hanger 8 is placed inside the casing head shell 2, and a double sealing form of a metal sealing ring 6 and an "O" type sealing ring 7 is adopted between them. The metal seal 6 is deformed and expanded under the deadweight of the hanging casing to achieve a sealing effect; the pointed top screw 9 and the flat top screw 11 are tightened in the top screw groove under the action of external force. The upper end of the mandrel hanger 8 is processed with a 45° chamfer, and the pointed top screw 9 is tightened so that the pointed corner of the pointed top screw 9 is pressed tightly against the outer chamfer of the upper end of the casing hanger 8 to prevent the casing hanger 8 from moving up and down longitudinally. A stop groove is designed on the periphery of the mandrel hanger 8, and the flat head top screw 11 is tightened so that the flat head of the flat head top screw 11 is pressed tightly against the stop groove of the casing hanger 8 to prevent the casing hanger 8 from moving left and right laterally. When the casing taper sealing thread is damaged or the surface casing is not installed in place, the slip hanger 16 and the inverted slip device 17 can be used. The slip hanger 16 is placed inside the casing head housing 8, and a rectangular rubber ring 17 is used to seal it. The pointed top screw 9 is tightened to press The slip hanger 16 expands the rectangular rubber ring 17 to achieve a sealing effect. The oil layer casing passes through the slip hanger 16, and the slip teeth are in close contact with the oil layer casing. Under the weight of the oil layer casing, the slip teeth are stimulated to clamp the casing to complete the function of hanging the oil layer casing; the inverted slip device 18 is connected to the lower part of the casing head shell with bolts 19, and the surface casing passes through the inverted slip device 18 and the BT sealing ring 4. The slip teeth are in close contact with the surface casing, and tightening the connecting bolts 19 causes the slip teeth to bite the surface casing to achieve the purpose of hanging the surface casing. Sealing grease is injected into the BT sealing groove in the casing head shell through the grease injection valve 3, so that the BT sealing ring 4 hugs the outer wall of the casing to form a sealing structure.

[0020] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A casing head device with multiple structures, comprising: Lifting chassis, casing head housing, grease injection valve, BT sealing ring, threaded flange, metal sealing ring, "O" type sealing ring, mandrel hanger, pointed top screw, extended single male short joint, flat top screw, pressure gauge assembly, instrument flange, flat gate valve, pressure relief valve, slip hanger, rectangular sealing ring, inverted slip device, bolt; characterized in that: the casing head housing is processed with a tapered sealing surface, the upper flange is added with a top screw groove, the inner side of the lower end is processed with a tapered sealing internal thread and a BT sealing ring groove in sequence, the grease injection valve and the pressure relief valve are respectively installed on the periphery of the BT sealing ring groove, the BT sealing ring groove is placed in the BT sealing ring groove, the surface casing is connected to the tapered sealing internal thread of the casing head housing, and the lifting chassis is welded to the lower end of the casing head housing to adjust the level and height of the casing head; flow channel holes are processed on both sides of the casing head housing, one side is connected to the threaded flange, and the other side is connected to the flat gate valve, the instrument flange, and the pressure gauge assembly in sequence to observe the changes in the internal pressure of the casing head.

2. A multi-structure casing head device as claimed in claim 1, characterized in that: Two internal threads and a gasket groove are designed on the upper end of the mandrel hanger. The upper thread is processed with a reverse trapezoidal internal thread to facilitate the lifting of the tool. The lower thread is processed with a tapered sealing internal thread to connect the extended single male short joint. The metal gasket installed in the gasket groove is used to connect the seal of the high-pressure wellhead device. The lower end of the mandrel hanger is designed as an integrated unit with the double male short joint, and the lower end is processed with a tapered sealing external thread to connect with the oil layer casing.

3. A multi-structure casing head device as claimed in claim 1, characterized in that: The mandrel hanger is placed inside the casing head shell, and a double sealing form of metal sealing ring and "O" type sealing ring is adopted between them. The metal seal deforms and expands under the dead weight of the hanging casing to achieve a sealing effect.

4. A multi-structure casing head device as claimed in claim 1, characterized in that: The pointed top screw and the flat top screw are tightened in the top screw groove under the action of external force. The upper end of the mandrel hanger is processed with a 45° chamfer. The pointed top screw is tightened so that the tip of the pointed top screw is pressed tightly against the upper outer chamfer of the casing hanger to prevent the casing hanger from moving vertically up and down. A stop groove is designed on the periphery of the mandrel hanger. The flat top screw is tightened so that the flat head of the flat top screw is pressed tightly against the stop groove of the casing hanger to prevent the casing hanger from moving horizontally left and right.

5. A multi-structure casing head device as claimed in claim 1, characterized in that: When the casing taper sealing thread is damaged, or the surface casing is not installed in place, the slip hanger and the inverted slip device can be used. The slip hanger is placed inside the casing head shell and sealed with a rectangular rubber ring. Tighten the pointed top screw and press the slip hanger to expand the rectangular rubber ring to achieve a sealing effect. The oil layer casing passes through the slip hanger, and the slip teeth are in close contact with the oil layer casing. Under the weight of the oil layer casing, the slip teeth are activated to clamp the casing to complete the function of hanging the oil layer casing.

6. A multi-structure casing head device as claimed in claim 1, characterized in that: The inverted slip device is connected to the lower part of the casing head shell with bolts. The surface casing passes through the inverted slip device and the BT sealing ring. The slip teeth are in close contact with the surface casing. Tightening the connecting bolts causes the slip teeth to bite the surface casing to achieve the purpose of hanging the surface casing. Sealing grease is injected into the BT sealing groove in the casing head shell through the grease injection valve, so that the BT sealing ring holds the outer wall of the casing to form a sealing structure.

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