Drill barrel with gas-liquid two-phase interface pressure balanced sealing rotary joint

Abstract

A kind of drill cylinder with gas-liquid two-phase interface pressure balance sealing rotary joint, annular water chamber of rotary joint in the drill cylinder is provided with annular gas chamber on both sides, annular gas chamber can form two gas seals after being connected with compressed gas on both sides of annular water chamber, gas seal ring can provide high-pressure gas from the contact surface of inner fixed ring and outer rotating ring to annular water chamber of rotary joint, annular water chamber is formed on both sides to form gas-liquid two-phase interface pressure balance sealing, to avoid internal sealing structure being damaged by sand in water, so as to ensure the high-pressure supply of cooling water at drill bit, ensure cooling effect, protect drill bit, further by setting two groups of humidity sensors, whether gas-liquid balance is realized, whether water supply is normal, and whether sealing structure is damaged and other problems can be accurately judged.

Description

Technical Field

[0001] This invention relates to the field of engineering pile foundation construction equipment technology, and in particular to a drill barrel with a gas-liquid two-phase interface pressure balance sealing rotary joint. Background Technology

[0002] During the construction of pile holes, existing rotary drilling rigs encounter rock strata at a certain depth. The cutting teeth or rollers at the lower end of the drill barrel of the rotary drilling rig have difficulty drilling. Furthermore, as the pile hole is drilled, mud, sand and fine rock fragments inside the pile hole will continuously coat the cutting teeth or rollers at the lower end of the drill barrel, causing the cutting teeth or rollers to heat up rapidly. This requires the drill barrel to be lifted frequently for cleaning, which not only causes rapid wear of the cutting teeth or rollers, high consumption, and high construction costs, but also seriously restricts the construction efficiency of pile holes.

[0003] To address this, Chinese invention patent number 202111516180.5 proposes an adaptive water pipe feeding and unloading drilling system. This system has pipe feeding and unloading devices and traction positioning devices on both sides of the upper end of the pile hole. When the drill barrel drills downwards into the pile hole, the outer rotating ring of the upper rotating joint of the drill barrel pulls down the water supply pipe inside the pipe feeding and unloading device. The downward pull causes the water supply pipe to tighten and press down on the roller-type pressure sensor A. A closed-loop control system is formed through sensor A, a motor, and an encoder, enabling the motor to control the speed of the pipe reel's rotation and unloading, adaptively matching the drilling speed of the drill barrel. The water supply pipe moves up and down synchronously with the drill barrel, continuously injecting water into the rotating joint. Furthermore, during the process of water supplying water into the rotating joint, the traction rope of the traction positioning device is also pulled downwards by the outer rotating ring of the upper rotating joint of the drill barrel. The tension of the traction rope overcomes the rotational force of the outer rotating ring as the inner fixed ring rotates, causing the outer... The rotating ring is in a relatively stationary state, ensuring a continuous and safe supply of water to the rotating joint. A water injection pipe is installed on the inner wall of the drill barrel's inner cylinder. This pipe sprays cooling water through the jacketed cylinder onto the sidewalls of the lower cutting teeth for flushing, slag removal, and cooling, addressing the aforementioned cutting tooth cooling issue. However, during drilling, as the depth increases and the drilling target changes (e.g., from mud to sand), a higher water pressure is needed for flushing the lower part. This increased pressure causes cooling water (which also contains a small amount of sand) to seep into the rotating joint from the contact surface between the inner fixed ring and the outer rotating ring. The sand in the cooling water causes severe wear between the inner fixed ring and the outer rotating ring, damaging the seals and weakening the rotating joint's sealing performance. This further leads to high-pressure water leakage, resulting in insufficient water supply to the lower cutting teeth, affecting their lifespan and operational efficiency. In actual drilling operations, the conventionally designed sealing structure between the inner fixed ring and the outer rotating ring has a short lifespan and poor sealing effect, seriously affecting the drilling operation. Furthermore, the rough mating surface of the rotating pair increases friction, causing excessive resistance during the rotation of the outer rotating ring, resulting in uneven rotation. This leads to increased tension on the surface high-pressure water supply pipe and its traction rope, making the high-pressure water supply pipe prone to entanglement. Therefore, it is necessary to invent a new type of rotary joint suitable for this drilling pipe to solve the sealing and leakage problems, further ensuring that the traction rope can effectively traction and suppress rotation. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a drill barrel with a gas-liquid two-phase interface pressure-balanced sealing rotary joint.

[0005] The technical solution of this invention is: a drill barrel with a gas-liquid two-phase interface pressure balance sealing rotary joint, comprising a drill barrel body, a rotary joint mounted on a drill barrel body support, and a water injection pipe installed inside the drill barrel body to provide cooling water to the cutting teeth at the lower end of the drill barrel body. The outer end of the water injection pipe is connected to a high-pressure water source. The rotary joint includes an inner fixing ring fixedly mounted on the drill barrel body support and an outer rotating ring matchedly mounted on the inner fixing ring. A rotary sealing structure is provided between the inner fixing ring and the outer rotating ring. An annular groove is provided in the middle of the side of the inner fixing ring along the circumferential direction. An annular water chamber is formed between the annular groove and the outer rotating ring. The rotating ring has a cooling water pipe connected to the annular water chamber in the middle of its side. The bottom surface of the inner fixed ring has a water outlet hole facing upwards. A through hole connects the water outlet hole and the annular water chamber, allowing cooling water to be introduced from the annular water chamber to the water outlet, and then from the water outlet into the water injection pipe. The lower end of the water outlet hole is connected to the upper end of the water injection pipe through a connector. The outer sides of the inner fixed ring on both sides of the annular water chamber have annular grooves along the circumference. These annular grooves and the outer rotating ring form an annular air chamber. A high-pressure air inlet pipe connected to the annular air chamber is provided on the side of the outer rotating ring, allowing gas to be introduced into the annular air chamber.

[0006] Preferably, a plurality of grooves are arranged around the outer side of the inner fixed ring in two layers between the annular water chamber and the annular air chamber. A plurality of humidity sensors A are arranged in the grooves of the layer near the annular water chamber, and a plurality of humidity sensors B are arranged in the grooves of the layer near the annular air chamber. Humidity sensors A and humidity sensors B are sensors with identical structures.

[0007] Preferably, the spacing between several humidity sensors A is the same, and the spacing between several humidity sensors B is the same.

[0008] Preferably, an annular groove is provided in the middle of the outer side of the inner fixing ring between the annular air chamber and the annular water chamber, and a sealing ring A is sleeved in the annular groove.

[0009] Preferably, an annular groove is provided in the middle of the inner side of the outer rotating ring between the annular air chamber and the end face of the outer rotating ring, and a sealing ring B is fitted inside the annular groove.

[0010] Preferably, flow meters are installed on the cooling water pipe and the high-pressure air intake pipe respectively.

[0011] Preferably, the outer end of the cooling water pipe is connected to a high-pressure water supply device and is equipped with a cooling water supply pressure adjustment unit; the outer end of the high-pressure air inlet pipe is connected to a high-pressure air supply device and is equipped with a high-pressure gas supply pressure adjustment unit; and a control module is also provided. Humidity sensor A and humidity sensor B transmit the acquired signals to the control module, and the control module sends adjustment signals to the two pressure adjustment units.

[0012] The beneficial technical effects of this invention are: (1) The rotary joint is equipped with humidity sensor A and humidity sensor B. Both are used to check the penetration of cooling water in the mating surface of the rotating joint. The detection signals of the two are used together to determine different working states. Then, based on this determination, the supply of high-pressure water source and high-pressure air source are adjusted to achieve balance and coordination between the two. It can keep the rotary joint in a state of pressure balance between the gas phase and liquid phase at all times, ensuring that the rotary joint is in the best sealing state during drilling, ensuring its rotation flexibility, and ensuring sufficient water supply at the lower cutting teeth, without affecting cooling and normal drilling, and ensuring the service life of the cutting teeth.

[0013] (2) Both sides of the annular water chamber of the rotary joint in the drill pipe are provided with annular air chambers. After compressed gas is introduced into the annular air chamber, two air-sealing rings can be formed on both sides of the annular water chamber. The air-sealing rings can push the gas into the annular water chamber from the contact surface of the inner fixed ring and the outer rotating ring, forming a balance between the gas phase and the liquid phase with the high-pressure water that permeates outward from the annular water chamber. This prevents the mud and sand from the cooling water from entering the mating surface of the rotating pair between the inner fixed ring and the outer rotating ring, ensuring its rotational flexibility. It can also prevent the outer rotating ring from being subjected to excessive resistance when rotating. Therefore, the high-pressure water supply pipe and traction rope on the ground surface will not be subjected to excessive tension, and the high-pressure water supply pipe will not be entangled, ensuring the continuous and efficient operation of the drill pipe.

[0014] (3) The rotary joint combines two sealing rings, plus the air seal between the inner fixed ring and the outer rotating ring, forming a special three-seal structure to ensure the sealing effect of the rotating pair and maximize the service life of the rotary joint. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a three-dimensional structural schematic diagram of the drill barrel of the present invention; Figure 3 This is a bottom-view structural diagram of the present invention; Figure 4 yes Figure 3 Sectional view along axis AA; Figure 5 yes Figure 4 A magnified view of a portion of the image; Figure 6 yes Figure 5 BB-direction sectional view; Figure 7 yes Figure 5 CC-direction sectional view; Figure 8 This is a flowchart illustrating the process of using the drill barrel of the present invention on a drilling rig.

[0016] In the diagram, 01. Drill barrel body, 11. Drill barrel body support, 02. Rotary joint, 21. Inner fixed ring, 22. Outer rotating ring, 23. Annular water chamber, 231. Cooling water pipe, 232. Water outlet, 233. Through hole, 234. Joint, 24. Annular air chamber, 241. High-pressure air inlet pipe, 25. Sealing ring A, 251. Sealing ring B, 26. Humidity sensor A, 261. Humidity sensor B, 27. Water injection pipe, 28. High-pressure air source, 29. High-pressure water source, 30. Flow meter. Detailed Implementation

[0017] Example 1, referring to Figures 1-8 in the specification, is a drill barrel with a gas-liquid two-phase interface pressure balance sealing rotary joint, including a drill barrel body, a rotary joint installed on a drill barrel body support, and a water injection pipe installed inside the drill barrel body to provide cooling water to the cutting teeth at the lower end of the drill barrel body. The specific structure and function of the drill barrel and its drilling system can be found in Chinese Invention Patent No. 202111516180.5.

[0018] The rotary joint includes an inner fixed ring fixedly fitted onto the drill barrel support and an outer rotating ring fitted onto the inner fixed ring. The inner fixed ring has an annular groove along its circumferential direction in the middle of its side surface, forming an annular water chamber between the groove and the outer rotating ring. A cooling water pipe communicating with the annular water chamber is located in the middle of the side surface of the outer rotating ring. The outer end of the cooling water pipe is connected to a high-pressure water source via a high-pressure water supply pipe, which supplies cooling water into the annular water chamber. The bottom surface of the inner fixed ring has an outlet hole facing upwards, and a through hole connects the outlet hole to the annular water chamber, allowing cooling water to enter through the through hole. The lower end of the outlet hole is connected to the upper end of a water injection pipe via a connector, allowing cooling water in the annular water chamber to flow into the water injection pipe. Inside the pipe; the outer sides of the inner fixed rings on both sides of the annular water chamber are provided with annular grooves along the circumference. An annular air chamber is formed between the annular grooves and the outer rotating ring. A high-pressure air inlet pipe communicating with the annular air chamber is provided on the side of the outer rotating ring. The cooling water pipe and the two high-pressure air inlet pipes are arranged adjacent to each other vertically. The air inlet pipes are connected to a high-pressure air source through high-pressure air pipes. After high-pressure gas is introduced into the annular air chamber, two air-sealing rings can be formed on both sides of the annular water chamber. The air-sealing rings can apply gas pressure outward from the contact surface of the inner fixed ring and the outer rotating ring for pushing. A gas phase and liquid phase balance is formed between the gas and liquid phases and the high-pressure water that permeates outward from the annular water chamber, ensuring that the cooling water does not enter the mating surface of the rotating pair and ensuring the flexible rotation of the rotating pair.

[0019] Between the annular water chamber and the annular air chamber, there are several grooves arranged around the outer side of the inner fixed ring in two layers. Several humidity sensors (Type A) are installed in the grooves of the layer closest to the annular water chamber, and several humidity sensors (Type B) are installed in the grooves of the layer closest to the annular air chamber. Humidity sensors A and B work together, and their combined detection signals are used to determine the degree of cooling water penetration, providing guidance for the specific pressure control of the high-pressure air and high-pressure water sources.

[0020] The spacing between several humidity sensors A is the same, and the spacing between several humidity sensors B is the same.

[0021] An annular groove is provided in the middle of the outer side of the inner fixed ring between the annular air chamber and the annular water chamber, and a sealing ring A is fitted inside the annular groove; an annular groove is provided in the middle of the inner side of the outer rotating ring between the annular air chamber and the end face of the outer rotating ring, and a sealing ring B is fitted inside the annular groove. The sealing rings A and B provide secondary protection to prevent cooling water from entering between the inner fixed ring and the outer rotating ring.

[0022] The cooling water pipe is connected to a high-pressure water supply device at its outer end and is equipped with a cooling water supply pressure adjustment unit. The high-pressure air intake pipe is connected to a high-pressure air supply device at its outer end and is equipped with a high-pressure gas supply pressure adjustment unit. A control module is also provided. Humidity sensors A and B transmit acquired signals to the control module, which then sends adjustment signals to the two pressure adjustment units. The high-pressure air intake pipe, along with the cooling water pipe, is attached to the traction rope of the adaptive water pipe retraction drilling system described in Chinese Patent 202111516180.5. It is retracted and extended along with the traction rope; the specific retraction and extension process is detailed in the specification of that patent.

[0023] The working process and principle of this invention are as follows: First, the drill barrel is installed at the lower end of the drill rod of the rotary drilling rig, and two high-pressure air inlet pipes are connected to the high-pressure air source respectively. The cooling water pipe on the rotary joint is connected to the high-pressure water source. Second, the rotary drilling rig is started, and the drill barrel rotates downward to drill a hole. The high-pressure water source injects cooling water into the annular water chamber inside the rotary joint through the cooling water pipe. The annular water chamber then supplies cooling water to the water injection pipe through the joint, thus rinsing and cooling the drill bit while it is drilling. Third, as the drilling depth increases, the drilling object encountered at the lower end of the drill bit changes, the rinsing difficulty gradually increases, and the water pressure in the cooling water pipe gradually increases. At this time, the airtight ring... Air pressure is applied from the contact surface between the inner fixed ring and the outer rotating ring towards the annular water chamber in the center of the rotary joint. The high-pressure gas can form a gas-liquid two-phase equilibrium interface with the cooling water, which can effectively prevent the cooling water from seeping into the space between the inner fixed ring and the outer rotating ring from the contact surface. In the fourth step, during the drilling process, humidity sensor A and humidity sensor B can transmit the signal of cooling water seepage to the control unit of the high-pressure water source in a timely manner. With the cooperation of the signals from sensor A and sensor B, by controlling the supply pressure of the external high-pressure water source and high-pressure gas source, the rotary joint can be kept in a gas-liquid balance state at all times, ensuring that the rotary joint is in the best sealing state during the drilling process.

[0024] The combination of humidity sensors A and B can also achieve the following functions: 1. Inspection during drill barrel startup: By observing the ebb and flow of the supply pressures of the high-pressure air source and the high-pressure water source, and combining this with the humidity signal changes from humidity sensors A and B, it is determined whether the cooling water pipes and air pipes can supply the rotary joint, which is used for the detection process when the drill barrel is started.

[0025] 1.1 First, run the cooling water supply at high pressure and the high-pressure air supply at low pressure for a period of time. If the humidity sensor A can detect the humidity signal, it means that the high-pressure water supply pipeline of the drill barrel is unobstructed and can supply water to the rotary joint. Otherwise, it is not unobstructed and the water pipe needs to be repaired.

[0026] 1.2 After completing 1.1 and confirming that the high-pressure water supply pipeline is unobstructed, reduce the cooling water supply pressure and simultaneously increase the high-pressure air supply pressure. After running in this state for a period of time, if humidity sensor A can continuously detect a humidity signal, it indicates that the air pipe is blocked and needs to be repaired; if humidity sensor A changes from having a humidity signal to not having a humidity signal, it indicates that the air pipe is unobstructed and can supply air to the rotary joint.

[0027] 2. During normal drilling, the high-pressure supply of external cooling water is activated to flush the lower drill bit, and the gas supply of external high-pressure gas source is activated. The gas and cooling water form a gas-liquid two-phase interface pressure balance and sealing state in the rotary joint to protect the internal sealing structure of the rotary joint. 2.1. Increasing the water pressure causes an imbalance between gas and liquid. A new equilibrium is formed by subsequently increasing the air pressure. Of course, as the drilling target changes, the flushing difficulty and cooling requirements are different, which will require different cooling water supply pressure. This will require adjustment of the cooling water supply pressure. For example, as mentioned in the background technology, when the drilling speed, slag removal requirements and cooling requirements increase from mud to sand and gravel, the cooling water pressure needs to be increased. After running for a period of time with the cooling water supply pressure increased, humidity sensor B will detect a humidity signal, indicating that the gas-liquid balance has occurred. At this time, the supply pressure of high-pressure air is gradually increased. If humidity sensor B gradually becomes without a humidity signal, while humidity sensor A still maintains a humidity signal, it means that the high-pressure air and high-pressure cooling water have formed a new gas-liquid balance in the working surface of the rotating joint. 2.2. Lowering the water pressure causes an imbalance between gas and liquid; a new equilibrium is formed by lowering the air pressure accordingly. Of course, as the drilling target changes, the flushing difficulty and cooling requirements are different, which will require different cooling water supply pressures. This will lead to adjustments in the cooling water supply pressure. For example, if the drilling target changes from sand and gravel to soil, soil is relatively easier to remove slag and flush, so the cooling water pressure will be lowered accordingly. After running for a period of time with the cooling water supply pressure lowered, humidity sensors A and B will not detect any humidity signal, indicating that there is an imbalance between gas and liquid. At this time, the supply pressure of high-pressure air is gradually reduced. If humidity sensor A gradually becomes a humidity signal while humidity sensor B remains a no-humidity signal, it means that a new gas-liquid balance has been formed between high-pressure air and high-pressure cooling water in the working surface of the rotating joint. The above two gas-liquid imbalance adjustment processes are a gradual adjustment and adaptation process. Based on the signals from humidity sensors A and B and the supply pressure values, we can summarize the adaptation experience and rules between gas and liquid under different working conditions. In this way, we can form a suitable gas-liquid balance scheme based on the drill pipe depth, the material of the drilling object, the rotation speed, etc., which is beneficial for guiding other drilling projects in the later stage. If the adjustment processes in 2.1 and 2.2 still detect water by humidity sensors A and B no matter how they are adjusted, and increasing the air pressure cannot solve the problem, it means that the sealing structure has been damaged and the rotary joint needs to be repaired.

[0028] Example 2: Example 2 is basically the same as Example 1, and the similarities will not be repeated. The difference is that flow meters are installed on the cooling water pipe and the high-pressure air inlet pipe respectively, which are used to detect the flow in the two pipes in real time during the operation of the drill barrel, so as to determine whether the supply of the two is normal. Of course, the signals of humidity sensors A and B can also be combined to make a comprehensive judgment on the pipeline. The judgment process is similar to the start detection part of Example 1, and will not be described again.

Claims

1. A drill barrel with a gas-liquid two-phase interface pressure-balanced sealing rotary joint, comprising a drill barrel body, a rotary joint mounted on a drill barrel body support, and a water injection pipe installed inside the drill barrel body to provide cooling water to the cutting teeth at the lower end of the drill barrel body, characterized in that: The rotary joint includes an inner fixed ring fixedly mounted on the drill barrel support and an outer rotating ring matchedly mounted on the inner fixed ring. The inner fixed ring has an annular groove in the middle of its side surface along the circumferential direction, forming an annular water chamber between the annular groove and the outer rotating ring. The outer rotating ring has a cooling water pipe in the middle of its side surface that communicates with the annular water chamber. The bottom surface of the inner fixed ring has a water outlet hole facing upwards, and a through hole communicates with the annular water chamber. The lower end of the water outlet hole is connected to the upper end of the water injection pipe through a connector. The outer sides of the inner fixed ring on both sides of the annular water chamber have annular grooves in the circumferential direction, forming an annular air chamber between the annular groove and the outer rotating ring. A high-pressure air inlet pipe communicating with the annular air chamber is provided on the side of the outer rotating ring. Between the annular water chamber and the annular air chamber, there are several grooves arranged around the outer side of the inner fixed ring in two layers. Several humidity sensors A are installed in several grooves in the layer near the annular water chamber, and several humidity sensors B are installed in several grooves in the layer near the annular air chamber. The cooling water pipe is connected to a high-pressure water supply device at its outer end and is equipped with a cooling water supply pressure adjustment unit. The high-pressure air inlet pipe is connected to a high-pressure air supply device at its outer end and is equipped with a high-pressure gas supply pressure adjustment unit. A control module is also provided. Humidity sensor A and humidity sensor B will transmit the acquired signals to the control module, and the control module will send adjustment signals to the two pressure adjustment units.

2. A drill barrel with a gas-liquid two-phase interface pressure-balanced sealing rotary joint according to claim 1, characterized in that: The spacing between several humidity sensors A is the same, and the spacing between several humidity sensors B is the same.

3. A drill barrel with a gas-liquid two-phase interface pressure-balanced sealing rotary joint according to claim 1, characterized in that: An annular groove is provided in the middle of the outer side of the inner fixing ring between the annular air chamber and the annular water chamber, and a sealing ring A is fitted inside the annular groove.

4. A drill barrel with a gas-liquid two-phase interface pressure-balanced sealing rotary joint according to claim 1, characterized in that: An annular groove is provided in the middle of the inner side of the outer rotating ring between the annular air chamber and the end face of the outer rotating ring, and a sealing ring B is fitted inside the annular groove.

5. A drill barrel with a gas-liquid two-phase interface pressure-balanced sealing rotary joint according to claim 1, characterized in that: Flow meters are installed on the cooling water pipe and the high-pressure air inlet pipe, respectively.

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