CN114320275A - Emergency release working condition simulation test method - Google Patents
Emergency release working condition simulation test method Download PDFInfo
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- CN114320275A CN114320275A CN202210007883.3A CN202210007883A CN114320275A CN 114320275 A CN114320275 A CN 114320275A CN 202210007883 A CN202210007883 A CN 202210007883A CN 114320275 A CN114320275 A CN 114320275A
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- emergency release
- blowout preventer
- outer cylinder
- sealing outer
- simulation test
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- 238000004088 simulation Methods 0.000 title claims abstract description 22
- 238000010998 test method Methods 0.000 title claims abstract description 18
- 238000007789 sealing Methods 0.000 claims abstract description 64
- 238000000034 method Methods 0.000 claims abstract description 27
- 238000005553 drilling Methods 0.000 claims abstract description 23
- 238000012360 testing method Methods 0.000 claims abstract description 6
- 238000010008 shearing Methods 0.000 claims description 14
- 230000008569 process Effects 0.000 claims description 13
- 229910000831 Steel Inorganic materials 0.000 claims description 7
- 239000010959 steel Substances 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 5
- 230000000694 effects Effects 0.000 claims description 4
- 238000003825 pressing Methods 0.000 claims description 3
- 238000012544 monitoring process Methods 0.000 claims description 2
- 230000007246 mechanism Effects 0.000 abstract description 4
- 230000009471 action Effects 0.000 description 5
- 238000000926 separation method Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000013519 translation Methods 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
- 238000011179 visual inspection Methods 0.000 description 1
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Abstract
The invention relates to an emergency release working condition simulation test method. The invention relates to an emergency release working condition simulation test method, which is used for a simulation test of a riser emergency release device, wherein the emergency release device comprises a sealing outer cylinder, a body and a blowout preventer, the sealing outer cylinder is arranged on the periphery of the upper end of the body, and the blowout preventer is arranged at the lower end of the body, and the method comprises the following steps: providing a lifting force to a sealing outer cylinder of the emergency release device so as to simulate the dragging force of a drilling ship to a marine riser system in an emergency; connecting a blowout preventer of the riser emergency release device with a hydraulic station to provide power for the blowout preventer to close a well; when the sealing outer cylinder begins to be separated from the body of the riser emergency release device, hydraulic power connected with the blowout preventer is communicated, so that the blowout preventer begins to be closed, and the blowout preventer is closed before the sealing outer cylinder is completely separated. The invention has simple and convenient operation, can be completed without needing too many external mechanisms, and has great popularization and application values.
Description
Technical Field
The invention relates to the technical field of offshore oil drilling and production equipment, in particular to an emergency release working condition simulation test method.
Background
The marine drilling riser is a liquid conveying pipeline for communicating an underwater wellhead with a drilling platform, the riser emergency release device is arranged between the underwater wellhead and a single riser, and when a drilling well encounters extreme severe sea conditions or other emergency situations, in order to avoid serious damage to a riser system and the wellhead, at the moment, the drilling riser and the wellhead need to be released emergently so that the drilling platform (or a drilling ship) can be evacuated quickly. The emergency release device of the marine riser consists of a sealing outer cylinder, a shearing pin, a one-way valve, a blowout preventer and other components. The sealing outer cylinder can be separated from the riser emergency release device in emergency, and the well plugging device is closed and plugged when the sealing outer cylinder is separated. Although the emergency release failure of the drilling riser is rare, once the emergency release failure occurs, the drilling ship can not be evacuated in time, and the safety of human life, environment and property is seriously threatened, so the reliability of the emergency release failure is particularly important for the safety of drilling operation.
How to accurately and simply simulate the emergency release of the marine riser becomes a research problem in the field.
Disclosure of Invention
In view of the above, the present invention is directed to provide an emergency release condition simulation test method for verifying the reliability and integrity of a riser emergency release device.
The invention provides an emergency release working condition simulation test method, which is used for a simulation test of a riser emergency release device, wherein the emergency release device comprises a sealing outer cylinder, a body and a blowout preventer, the sealing outer cylinder is arranged on the periphery of the upper end of the body, the blowout preventer is arranged on the lower end of the body, and the method comprises the following steps:
providing a lifting force to a sealing outer cylinder of the emergency release device so as to simulate the dragging force of a drilling ship to a marine riser system in an emergency;
connecting a blowout preventer of the riser emergency release device with a hydraulic station to provide power for the blowout preventer to close a well;
when the sealing outer cylinder begins to be separated from the body of the riser emergency release device, hydraulic power connected with the blowout preventer is communicated, so that the blowout preventer begins to be closed, and the blowout preventer is closed before the sealing outer cylinder is completely separated.
According to an embodiment of the invention, the method further comprises: and (4) pressing the well sealer by a pressurizing device to check the well sealing effect.
According to an embodiment of the invention, the method further comprises: and hoisting the sealing outer cylinder by a crane or a crown block to provide lifting force for the sealing outer cylinder of the emergency release device.
According to one embodiment of the invention, the crane or crown block is on the same axis as the outer sealing cylinder or at a certain offset angle.
According to an embodiment of the invention, the method further comprises: and shearing the shear pin when the sealing outer cylinder is lifted up so that the sealing outer cylinder starts to be separated from the body of the riser emergency release device.
According to one embodiment of the invention, when the outer sealing cylinder starts to separate from the body of the riser emergency release device, the one-way valve connected with the blowout preventer is opened, the hydraulic power of the blowout preventer is communicated, and the blowout preventer starts to close.
According to one embodiment of the invention, the blowout preventer is adapted to verify the ability to shear the drill pipe during a shut-in by shearing a wire suspended inside the riser emergency release device simulating the drill pipe during the shut-in.
According to one embodiment of the invention, the method further comprises a tie-back procedure for driving another set of shear pins to extend by means of the hydraulic station to re-lock the emergency release device.
According to an embodiment of the invention, the method further comprises: and monitoring the completion of the shut-in of the blowout preventer within a specified time by observing the shut-in indication on the blowout preventer and timing.
According to one embodiment of the invention, the normally open overflow of the hydraulic station is used as an energy accumulator, so that the one-way valve is opened in the separation process of the sealing outer cylinder and the body, and the liquid of the hydraulic station can automatically trigger the action of the well sealer to realize the well sealing operation.
The invention simulates the damage tension force generated by the heave and drift of a drilling platform (or a drilling ship) on the marine riser through the lifting force, verifies the shearing performance of the shear pin of the emergency release device of the marine riser and enables the sealing outer cylinder to be separated from the emergency release device at the lower part of the marine riser. The invention has simple and convenient operation, can be completed without needing too many external mechanisms, and has great popularization and application values.
Drawings
Fig. 1 is a schematic structural view of a riser emergency release simulation according to an embodiment of the present invention;
reference numerals: 1. the device comprises a crane, a crown block, 2. a sealing outer cylinder, 3. a supercharging device, 4. a steel wire, 5. a shearing pin, 6. a test base, 7. an indicating rod, 8. a blowout preventer, 9. a one-way valve, 10. a marine riser emergency release device and 11. a hydraulic station.
Detailed Description
The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the objects, features and advantages of the invention can be more clearly understood. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the present invention, but are merely intended to illustrate the spirit of the technical solution of the present invention.
The invention verifies the shearing performance of the shear pin of the riser emergency release device by simulating the damage tension force generated by the heave and drift of a drilling platform (or a drilling ship) on the riser, so that the sealing outer cylinder is separated from the riser lower emergency release device. The hydraulic station is used as an energy accumulator, in the separation process of the sealed outer cylinder and the sealed inner cylinder, the reversing indication is released, the one-way valve is opened, the well sealer is automatically triggered to act, and the liquid of the hydraulic station can complete the well sealing operation. The tieback performance of the riser emergency release device is completed by tieback of the sealed outer cylinder and locking the shear pin by a simulated drilling platform (or a drilling ship).
The technical scheme adopted by one embodiment of the invention is as follows:
as shown in fig. 1, riser emergency release 10 is mounted on test bed 6 and fixed to the ground. The sealing outer cylinder 2 is hung on a lifting hook of the crane/overhead traveling crane 1 through a steel wire rope, and the crane/overhead traveling crane 1 provides lifting force of the sealing outer cylinder 2 to simulate dragging force of a drilling ship to a marine riser system in an emergency. The riser emergency release 10 is simultaneously connected to a hydraulic station 11 to power the blowout preventer 8. The hydraulic station 11 is opened and ready under pressure. The crane/overhead traveling crane 1 lifts the sealing outer cylinder 2, cuts off the shear pin 5 (the shear pin 5 is connected with the sealing outer cylinder 2 and the riser emergency release device 10), when the sealing outer cylinder 2 begins to be separated from the riser emergency release device 10, the one-way valve 9 is opened, hydraulic power is communicated, the well plugging device 8 begins to be closed, and the well plugging device 8 is closed before the sealing outer cylinder 2 is completely separated. And the blowout preventer 8 cuts off the steel wire 4 in the closing process, and then the well blowout preventer 8 is pressed through the pressurizing device 3, so that the well blowout preventer effect is checked. During the tie-back process, another set of shear pins can be driven out by the hydraulic station 11, locking the emergency release 10 again.
The lifting force of the sealing outer cylinder 2 is provided by a crane/overhead traveling crane 1, and the crane/overhead traveling crane 1 and the sealing outer cylinder 2 can be on the same axis or have a certain deflection angle.
When the crane/overhead traveling crane 1 lifts the sealing outer cylinder 2 to begin to separate from the riser emergency release device 10, the blowout preventer 8 is started and begins to be closed, and the blowout preventer 8 is closed before the sealing outer cylinder 2 is completely separated; the completion of the shut-in of the blowout preventer within a specified time is monitored by visual inspection of the indicator rod 7 on the blowout preventer 8 and timing.
The invention has the technical characteristics that:
1. the lifting and translation of the crane/overhead traveling crane simulate the heaving and drifting movements of the drilling ship under sea waves and ocean currents, and the shearing and the releasing of the shear pin on the sealing outer cylinder of the riser emergency releasing device are simply and conveniently realized.
2. Normally open overflow is used as an energy accumulator through the hydraulic station, in the separation process of the sealed outer cylinder and the sealed inner cylinder, the one-way valve is opened, and liquid of the hydraulic station can automatically trigger the action of the well plugging device, so that well plugging operation is realized.
3. The drilling rod is simulated by shearing the steel wire suspended in the riser emergency release device, and the drilling rod shearing capacity in the well sealing process is verified.
4. And (4) pressing the lower part of the emergency release device of the marine riser through an external pressure enhancement device, and verifying the well sealing performance after the emergency release device is released.
5. The required closing time of the blowout preventer can be obtained by observing the indicating rod of the blowout preventer through visual observation, so that whether the blowout preventer is closed or not is verified when the sealing outer cylinder is completely separated.
The method has the advantages that the release process of the riser emergency release device under the emergency condition can be simulated in a factory, and whether the well plugging operation can be completed or not when the riser emergency release device is completely released is detected, so that the functional integrity and the reliability of the riser emergency release device are verified, the operation is simple and convenient, the release can be completed without using too many external mechanisms, and the method has great popularization and application values.
Examples
As shown in fig. 1, riser emergency release 10 is connected to test bed 6 and fixed to the ground. The pipeline of the hydraulic station 11 is connected to the riser emergency release device 10. The outer sealing cylinder 2 of the riser emergency release device 10 is hung from the crane 1 by a wire rope.
When the hydraulic station works, the hydraulic station 11 is started and is reserved for pressure. The crane/overhead traveling crane 1 lifts the sealing outer cylinder 2, the sealing outer cylinder 2 pulls the shearing pin to cut the shearing pin 5, and the sealing outer cylinder 2 starts to be separated from the riser emergency release device 10; at the same time, it is confirmed that the blowout preventer 8 starts to close by observing the external indicating mechanism of the blowout preventer 8. The crane/overhead traveling crane 1 continues to slowly lift the sealing outer cylinder 2, or the crane/overhead traveling crane 1 slowly lifts the sealing outer cylinder 2 after deviating for a certain distance until the sealing outer cylinder 2 is completely separated from the riser emergency release device 10. When the sealing outer cylinder 2 is separated, the blowout preventer 8 is completely closed. The well plugging device is provided with a pressurizing device 3, the well plugging device 8 cuts off a steel wire 4 (the steel wire 4 penetrates through the well plugging device) in the closing process, and then the well plugging device 8 is pressed through the pressurizing device 3, so that the well plugging effect is checked. During the tie-back process, another set of shear pins can be driven out by the hydraulic station 11, locking the emergency release 10 again.
The implementation mode can also be as follows: the crane/overhead traveling crane 1 lifts the outer sealing cylinder 2, so that the outer sealing cylinder 2 starts to be separated from the riser emergency release device 10, and meanwhile, the blowout preventer 8 is confirmed to start to be closed; and simultaneously, timing is started until the blowout preventer 8 is completely closed, and the integrity and the efficiency of the closed blowout preventer are checked.
It should be noted that, in this document, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the system or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention; relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
In addition, in the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The foregoing embodiments are merely illustrative of the present invention, and various components and devices of the embodiments may be changed or eliminated as desired, not all components shown in the drawings are necessarily required, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments described herein, and all equivalent changes and modifications based on the technical solutions of the present invention should not be excluded from the scope of the present invention.
Claims (10)
1. The emergency release working condition simulation test method is used for simulation test of a riser emergency release device, the emergency release device comprises a sealing outer barrel, a body and a blowout preventer, the sealing outer barrel is arranged on the periphery of the upper end of the body, and the blowout preventer is arranged at the lower end of the body, and the emergency release working condition simulation test method is characterized by comprising the following steps of:
providing a lifting force to a sealing outer cylinder of the emergency release device so as to simulate the dragging force of a drilling ship to a marine riser system in an emergency;
connecting a blowout preventer of the riser emergency release device with a hydraulic station to provide power for the blowout preventer to close a well;
when the sealing outer cylinder begins to be separated from the body of the riser emergency release device, hydraulic power connected with the blowout preventer is communicated, so that the blowout preventer begins to be closed, and the blowout preventer is closed before the sealing outer cylinder is completely separated.
2. The emergency release condition simulation test method according to claim 1, further comprising: and (4) pressing the well sealer by a pressurizing device to check the well sealing effect.
3. The emergency release condition simulation test method according to claim 1 or 2, further comprising: and hoisting the sealing outer cylinder by a crane or a crown block to provide lifting force for the sealing outer cylinder of the emergency release device.
4. The emergency release working condition simulation test method according to claim 3, wherein the crane or the crown block and the sealing outer cylinder are on the same axis or have a certain deflection angle.
5. The emergency release condition simulation test method according to claim 1, 2 or 4, further comprising: and shearing the shear pin when the sealing outer cylinder is lifted up so that the sealing outer cylinder starts to be separated from the body of the riser emergency release device.
6. The emergency release condition simulation test method according to claim 1, 2 or 4, wherein when the sealing outer cylinder starts to separate from the body of the riser emergency release device, the one-way valve connected with the blowout preventer is opened, hydraulic power of the blowout preventer is communicated, and the blowout preventer starts to close.
7. The emergency release condition simulation test method of claim 1, 2 or 4, wherein the blowout preventer is used for verifying the capability of shearing the drill pipe during the shut-in process by shearing a steel wire of the simulated drill pipe suspended inside the riser emergency release device during the shut-in process.
8. The emergency release condition simulation test method according to claim 1, 2 or 4, wherein the method further comprises a tie-back process of driving another set of shear pins to extend through a hydraulic station to re-lock the emergency release device.
9. The emergency release condition simulation test method according to claim 1, 2 or 4, further comprising: and monitoring the completion of the shut-in of the blowout preventer within a specified time by observing the shut-in indication on the blowout preventer and timing.
10. The emergency release working condition simulation test method according to claim 1, 2 or 4, wherein a normally open overflow of a hydraulic station is used as an energy accumulator, so that in the process of releasing the sealing outer cylinder from the body, a one-way valve is opened, and the liquid of the hydraulic station can automatically trigger a well sealer to act, so that well sealing operation is realized.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202210007883.3A CN114320275A (en) | 2022-01-05 | 2022-01-05 | Emergency release working condition simulation test method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210007883.3A CN114320275A (en) | 2022-01-05 | 2022-01-05 | Emergency release working condition simulation test method |
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2022
- 2022-01-05 CN CN202210007883.3A patent/CN114320275A/en active Pending
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