A liquid loading and unloading crane pipe for preventing residual liquid from accumulating

Abstract

A liquid loading and unloading crane pipe for preventing residual liquid from accumulating, comprising a liquid phase arm pipe and a liquid phase vertical pipe for conveying liquid, wherein the inlet end of the liquid phase arm pipe is connected to a vertically arranged liquid phase inlet flange pipe through a first rotating joint, and the outlet end of the liquid phase arm pipe is connected to the liquid phase vertical pipe, and a residual liquid suction straw is passed through the liquid phase arm pipe and the liquid phase vertical pipe, wherein the inlet end of the residual liquid suction straw is arranged in the liquid phase inlet flange pipe and communicated with the inner cavity of the liquid phase inlet flange pipe; the residual liquid suction straw extends through the liquid phase arm pipe to the lower part of the liquid phase vertical pipe, and the horizontal position height of the outlet end of the residual liquid suction straw is lower than the height of its inlet end. The residual liquid suction straw can form a siphon effect to suck out the liquid retained in the crane pipe. This structure can automatically discharge the liquid retained in the crane pipe after loading and unloading is completed, without the need for manual or electronic system control. The added residual liquid suction straw basically does not affect the original structure of the crane pipe, and the added cost is very low, which is suitable for popularization and use.

Description

Technical Field

[0001] The invention relates to a liquid loading and unloading crane pipe, in particular to a liquid loading and unloading crane pipe which can prevent residual liquid from accumulating. Background Art

[0002] The crane pipe is a special equipment used in the fluid loading and unloading process of the petrochemical industry, also known as the fluid loading and unloading arm. It uses a rotating joint to connect with a rigid pipe and an elbow to realize the mobile equipment for transmitting liquid media between trains, tank cars and trestle storage and transportation pipelines. It has the characteristics of high safety, flexibility and long life. Common crane pipes include pipelines such as liquid phase arm pipes and liquid phase vertical pipes. The liquid phase arm pipe is connected to a liquid phase inlet flange pipe for connecting storage equipment such as oil removal tanks, and the liquid phase vertical pipe is used to insert the tank car to output liquid. At present, the liquid loading and unloading crane pipes are either pumped for loading and unloading, or siphon gravity loading and unloading. During the siphon gravity loading and unloading process, the liquid is first pumped into the crane pipe by a vacuum pump, and then the siphon effect is used to realize liquid transportation. In either case, after the loading and unloading is completed and the valve at the input end of the crane pipe is closed, some liquid will remain in the liquid phase inlet flange pipe. For volatile liquids such as gasoline and benzene, it is easy to spread into the air if they remain in the crane pipe, which poses a safety hazard. If there is too much liquid left, it is easy to overflow after expansion due to heat and cause pollution. In winter when the temperature is low, the remaining liquids such as benzene are easy to freeze and affect the pipeline. In order to solve the problem of liquid remaining in the crane pipe, some people propose to use nitrogen or other gases to purge and remove the residual liquid inside after loading and unloading, but the structure and operation of this equipment are too complicated and the cost is high. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the defect that liquid is easily retained in a crane pipe after loading and unloading, and to provide a liquid loading and unloading crane pipe which prevents the accumulation of residual liquid.

[0004] The technical solution adopted by the present invention to solve the above-mentioned technical problems is: a liquid loading and unloading crane pipe that prevents residual liquid accumulation, including a liquid phase arm pipe and a liquid phase vertical pipe for conveying liquid, the inlet end of the liquid phase arm pipe is connected to a vertically arranged liquid phase inlet flange pipe through a first rotating joint, the outlet end of the liquid phase arm pipe is connected to the liquid phase vertical pipe, a residual liquid suction pipe is passed through the liquid phase arm pipe and the liquid phase vertical pipe, the inlet end of the residual liquid suction pipe is arranged in the liquid phase inlet flange pipe and is connected to the inner cavity of the liquid phase inlet flange pipe; the residual liquid suction pipe passes through the liquid phase arm pipe and extends to the lower part of the liquid phase vertical pipe, and the horizontal position height of the residual liquid suction pipe outlet end is lower than the height of its inlet end.

[0005] The liquid phase arm pipe is composed of a liquid phase inner arm pipe and a liquid phase outer arm pipe. The inlet end of the liquid phase inner arm pipe is connected to a vertically arranged liquid phase inlet flange pipe through a first rotating joint, the outlet end of the liquid phase inner arm pipe is connected to one end of the liquid phase outer arm pipe through a second rotating joint, and the other end of the liquid phase outer arm pipe is connected to the liquid phase vertical pipe.

[0006] The residual liquid suction pipe extends from the inlet end of the liquid phase inlet flange pipe to the outlet end of the lower part of the liquid phase vertical pipe.

[0007] The horizontal position height of the outlet end of the residual liquid suction pipe is higher than the outlet end pipe opening of the lower part of the liquid phase vertical pipe.

[0008] The liquid phase vertical tube is also sleeved with a liquid phase outward extension tube that can extend downward, and the horizontal position height of the outlet end of the residual liquid suction tube is higher than the outlet end pipe opening at the lower part of the liquid phase vertical tube.

[0009] The residual liquid suction pipe is a hose which is passed through the liquid phase arm pipe and the liquid phase vertical pipe.

[0010] The residual liquid suction pipe is composed of multiple branch pipes connected together, and two branch pipes located at the connection between the liquid phase inner arm pipe and the liquid phase outer arm pipe are connected through a rotating pipe joint.

[0011] The rotating pipe joint is coaxially arranged with the rotating axis of the second rotating joint.

[0012] The inlet end of the lower part of the liquid phase inlet flange pipe is provided with an inlet flange for connecting to a liquid output valve.

[0013] A transmission mechanism for driving rotation is provided at both the first rotary joint and the second rotary joint.

[0014] A gas phase vertical pipe is sleeved on the outside of the liquid phase vertical pipe, and the gas phase vertical pipe is connected with a gas phase arm pipe.

[0015] The beneficial effects of the present invention are as follows: a residual liquid suction pipe is provided in the liquid phase arm pipe and the liquid phase vertical pipe, and the crane pipe and the residual liquid suction pipe jointly transport liquid during loading and unloading. After loading and unloading are completed and the output valve is closed, the residual liquid suction pipe can form a siphon effect to suck out the liquid retained in the crane pipe. This structure can automatically discharge the liquid retained in the crane pipe after loading and unloading is completed, without the need for manual or electronic system control. The added residual liquid suction pipe basically does not affect the original structure of the crane pipe, and the added cost is very low, which is suitable for popularization and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the liquid loading and unloading crane pipe of the present invention.

[0017] Figure 2 It is a structural schematic diagram of the inlet end portion of the crane pipe of the present invention.

[0018] Figure 3 It is a structural schematic diagram of the outlet end portion of the crane pipe of the present invention.

[0019] Figure 4 It is a structural schematic diagram of another embodiment of the residual liquid suction pipe.

[0020] Markings in the figure: 1. liquid phase arm pipe, 101. liquid phase inner arm pipe, 102. liquid phase outer arm pipe, 2. liquid phase vertical pipe, 3. first rotary joint, 4. liquid phase inlet flange pipe, 5. residual liquid suction pipe, 501. vertical hard pipe, 502. first interface flange, 503. intermediate connecting pipe, 504. sealing flange, 505. second interface flange, 6. second rotary joint, 7. inlet flange, 8. transmission mechanism, 9. column, 10. liquid phase extension pipe, 11. chain. DETAILED DESCRIPTION

[0021] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0022] like Figure 1 As shown, the liquid loading and unloading crane pipe of the present invention comprises a liquid phase arm pipe 1 and a liquid phase vertical pipe 2. The inlet end of the liquid phase arm pipe 1 is connected to a vertically arranged liquid phase inlet flange pipe 4 through a first rotary joint 3. The liquid phase inlet flange pipe 4 is connected to a storage device such as an oil removal tank. An inlet flange 7 for connecting a liquid output valve is provided at the inlet end of the lower part of the liquid phase inlet flange pipe 4. The outlet end of the liquid phase arm pipe 1 is connected to the liquid phase vertical pipe 2, and the liquid phase vertical pipe can be inserted into a tank truck to output liquid.

[0023] like Figure 1 As shown in FIG. 3 , a residual liquid suction pipe 5 is provided in the liquid phase arm pipe 1 and the liquid phase vertical pipe 2. The inlet end of the residual liquid suction pipe 5 is provided in the liquid phase inlet flange pipe 4 and communicated with the inner cavity of the liquid phase inlet flange pipe 4. The residual liquid suction pipe 5 extends through the liquid phase arm pipe 1 to the lower part of the liquid phase vertical pipe 2. During loading and unloading, the liquid is drawn into the liquid phase inlet flange pipe 4 and the liquid phase arm pipe 1, and is also drawn into the residual liquid suction pipe 5. At this time, the liquid is transported by the crane pipe and the residual night suction pipe inside it.

[0024] In the present invention, a residual liquid suction pipe is added in the crane pipe, and the horizontal position height of the residual liquid suction pipe outlet end is set to be lower than the height of its inlet end. After the conveying passage composed of the liquid phase arm pipe 1 and the liquid phase vertical pipe 2 stops conveying, the residual liquid suction pipe 5 continues to use the siphon effect to extract the liquid retained in the liquid phase inlet flange pipe 4. At this time, the gas can enter from the outlet end of the liquid phase vertical pipe 2, and flow to the liquid phase inlet flange pipe 4 through the liquid phase vertical pipe 2 and the liquid phase arm pipe 1, thereby compensating for the pressure reduction caused by the outflow of liquid from the liquid phase inlet flange pipe 4.

[0025] like Figure 1As shown, the liquid phase arm pipe 1 can be composed of a liquid phase inner arm pipe 101 and a liquid phase outer arm pipe 102. The inlet end of the liquid phase inner arm pipe 101 is connected to a vertically arranged liquid phase inlet flange pipe 4 through a first rotary joint 3, and the outlet end of the liquid phase inner arm pipe 101 is connected to one end of the liquid phase outer arm pipe 102 through a second rotary joint 6, and the other end of the liquid phase outer arm pipe 102 is connected to the liquid phase vertical pipe 2. A transmission mechanism 8 for driving rotation is provided at both the first rotary joint 3 and the second rotary joint 6. In order to adapt to the rotation between different sections of the liquid phase arm pipe 1, the residual liquid suction pipe 5 can be set as a hose, such as a rubber hose, that is inserted into the liquid phase arm pipe 1 and the liquid phase vertical pipe 2. When the liquid phase inner arm pipe 101 and the liquid phase outer arm pipe 102 rotate relative to each other, the residual liquid suction pipe 5 in the form of a hose can be bent arbitrarily without hindering the relative movement of the liquid phase inner arm pipe 101 and the liquid phase outer arm pipe 102. In this way, the residual liquid suction pipette 5 in the form of a hose only needs to ensure that it is inserted into the liquid phase arm pipe 1 and the liquid phase vertical pipe 2, and the approximate positions of its two ends are defined. Therefore, the residual liquid suction pipette 5 and the liquid phase arm pipe 1 and the liquid phase vertical pipe 2 basically do not need to be specially fixed. If necessary, it is only necessary to simply fix the two ends of the residual liquid suction pipette 5.

[0026] In the embodiment shown in the accompanying drawings, the residual liquid suction pipe 5 can also be a rigid pipe. In this embodiment, the residual liquid suction pipe 5 is composed of multiple sections of branch pipes, and the two branch pipes located at the connection between the liquid phase inner arm pipe 101 and the liquid phase outer arm pipe 102 are connected by a rotating pipe joint. The rotating pipe joint is coaxially arranged with the rotation axis of the second rotating joint, so as to ensure that the two sections of the residual liquid suction pipe 5 and the liquid phase inner arm pipe 101 and the liquid phase outer arm pipe 102 rotate coaxially without interfering with each other. In this embodiment, the residual liquid suction pipe 5 or its rotating pipe joint can be fixed by a bracket arranged inside the liquid phase inner arm pipe 101 or the liquid phase outer arm pipe 102, which ensures that its position is fixed.

[0027] like Figure 1 As shown in FIG. 3 , the inlet end of the residual liquid suction pipe 5 is as close as possible to the inlet end of the liquid phase inlet flange pipe 4 to ensure that after loading and unloading, the liquid in the liquid phase inlet flange pipe 4 can be completely extracted as much as possible through the residual liquid suction pipe 5. The residual liquid suction pipe 5 extends from the inlet end of the liquid phase inlet flange pipe 4 to the lower part of the liquid phase vertical pipe 2, and the outlet end of the residual liquid suction pipe 5 must have a sufficient height difference with its inlet end to ensure that the siphon effect can be smoothly formed.

[0028] like Figure 1 and 3As shown, the horizontal position height of the outlet end of the residual liquid suction pipe 5 is higher than the outlet end pipe opening of the lower part of the liquid phase vertical pipe 2. In this way, the height difference between the outlet end and the inlet end of the residual liquid suction pipe 5 is smaller than the height difference between the outlet end of the liquid phase vertical pipe 2 and the inlet end of the liquid phase inlet flange pipe 4, and the outlet end of the residual liquid suction pipe 5 is located inside the liquid phase vertical pipe 2. For the crane pipe without a gas phase recovery pipe or other devices such as a gas pressure balance valve, in the initial stage after the liquid output valve is closed after loading and unloading, as the liquid flows out through the crane pipe, the pressure in the liquid phase inlet flange pipe 4 will gradually decrease and form a negative pressure. Due to the negative pressure formed in the liquid phase inlet flange pipe 4, part of the liquid in the liquid phase vertical pipe 2 will enter from the outlet end of the residual liquid suction pipe 5 and reflux through the residual liquid suction pipe 5, so that the residual liquid suction pipe 5 is always full of liquid. When the liquid in the liquid phase vertical pipe 2 is discharged to a certain extent, the residual liquid suction pipe 5 begins to discharge liquid and forms a siphon effect to discharge all the liquid in the liquid phase inlet flange pipe 4. For the crane pipe connected with the gas phase recovery pipe or other devices such as the air pressure balance valve, after the loading and unloading is completed and the liquid output valve is closed, the shut-off valve or other air pressure balance valve between the reflux pipe of the gas phase recovery pipe and the liquid phase arm pipe 1 can be opened to destroy the negative pressure formed by the discharge of liquid from the liquid phase arm pipe 1, and the residual liquid suction pipe 5 can directly discharge all the liquid in the liquid phase inlet flange pipe 4 through the siphon action.

[0029] exist Figure 3 In the embodiment shown, the liquid phase vertical pipe 2 is also provided with a liquid phase external extension pipe 10 that can extend downward, and the liquid phase external extension pipe 10 can extend downward and deep into the tank car. In this embodiment, the horizontal position height of the outlet end of the residual liquid suction pipe 5 is still higher than the outlet end pipe opening at the lower part of the liquid phase vertical pipe, so as to prevent the lower end of the residual liquid suction pipe 5 from being exposed when the liquid phase external extension pipe 10 is retracted upward.

[0030] In such Figure 4In the illustrated embodiment, the residual liquid pipette 5 is in the form of a combination of a rigid pipeline and a flexible hose. The portion of the residual liquid pipette 5 that is inserted into the liquid phase vertical pipe 2 is a vertical hard pipe 501, which can maintain a vertical state and avoid friction or mutual entanglement with the chain 11 that controls the liquid phase external extension pipe 10 in the liquid phase vertical pipe 2. The other portions of the residual liquid pipette 5 are flexible hoses, which are convenient for inserting into the liquid phase arm pipe 1 with many bends and do not affect its rotation. In order to facilitate replacement of the residual liquid pipette 5 after loss, the elbow at the top of the vertical hard pipe 501 is inserted through the opening of the side wall of the liquid phase vertical pipe 2 and sealed and fixed, and the elbow that is inserted is provided with a first interface flange 502 so as to be connected with the other portions of the residual liquid pipette 5. An opening for the flexible hose of the residual liquid pipette 5 to pass through is provided on the side wall of the liquid phase external arm pipe 102 of the liquid phase arm pipe 1, and a second interface flange 505 is provided at the opening. The end of the residual liquid suction pipe 5 flexible hose exposed outside the opening is provided with a sealing flange 504, which can be sealed and fixedly connected with the second interface flange 505, so that the internal space of the liquid phase outer arm pipe 102 is kept in a closed state at the opening. While the sealing flange 504 is fixedly connected with the second interface flange 505, it can be connected with the first interface flange 502 through the intermediate pipe 503.

[0031] Other components of the liquid loading and unloading crane, such as the gas phase pipeline, the driving device, etc., can be referred to the prior art and will not be described in detail in this article.

Claims

1. A liquid loading and unloading crane pipe for preventing residual liquid from accumulating, comprising a liquid phase arm pipe (1) and a liquid phase vertical pipe (2) for conveying liquid, wherein the inlet end of the liquid phase arm pipe (1) is connected to a vertically arranged liquid phase inlet flange pipe (4) through a first rotating joint (3), and the outlet end of the liquid phase arm pipe (1) is connected to the liquid phase vertical pipe (2), characterized in that: A residual liquid suction pipe (5) is provided in the liquid phase arm pipe (1) and the liquid phase vertical pipe (2); the inlet end of the residual liquid suction pipe (5) is arranged in the liquid phase inlet flange pipe (4) and is communicated with the inner cavity of the liquid phase inlet flange pipe (4); the residual liquid suction pipe (5) passes through the liquid phase arm pipe (1) and extends to the lower part of the liquid phase vertical pipe (2), and the horizontal position height of the residual liquid suction pipe outlet end is lower than the height of its inlet end; the residual liquid suction pipe (5) extends from the inlet end of the liquid phase inlet flange pipe (4) to the lower part of the liquid phase vertical pipe (2); the horizontal position height of the outlet end of the residual liquid suction pipe (5) is higher than the outlet end pipe opening of the lower part of the liquid phase vertical pipe (2).

2. A liquid loading and unloading crane for preventing residual liquid accumulation as claimed in claim 1, characterized in that: The liquid phase arm pipe (1) is composed of a liquid phase inner arm pipe (101) and a liquid phase outer arm pipe (102); the inlet end of the liquid phase inner arm pipe (101) is connected to a vertically arranged liquid phase inlet flange pipe (4) via a first rotating joint (3); the outlet end of the liquid phase inner arm pipe (101) is connected to one end of the liquid phase outer arm pipe (102) via a second rotating joint (6); and the other end of the liquid phase outer arm pipe (102) is connected to the liquid phase vertical pipe (2).

3. A liquid loading and unloading crane for preventing residual liquid accumulation as claimed in claim 1, characterized in that: The liquid phase vertical tube (2) is also sleeved with a liquid phase external extension tube (10) that can extend downward, and the horizontal position of the outlet end of the residual liquid suction tube (5) is higher than the outlet end pipe opening at the bottom of the liquid phase vertical tube.

4. A liquid loading and unloading crane for preventing residual liquid accumulation as claimed in claim 1 or 2, characterized in that: The residual liquid suction pipe (5) is a hose that is inserted into the liquid phase arm pipe (1) and the liquid phase vertical pipe (2).

5. A liquid loading and unloading crane for preventing residual liquid accumulation as claimed in claim 2, characterized in that: The residual liquid suction pipe (5) is composed of a plurality of branch pipes connected together, and two branch pipes located at the connection between the liquid phase inner arm pipe (101) and the liquid phase outer arm pipe (102) are connected via a rotating pipe joint.

6. A liquid loading and unloading crane pipe for preventing residual liquid accumulation as claimed in claim 5, characterized in that: The rotating pipe joint is coaxially arranged with the rotating axis of the second rotating joint.

7. A liquid loading and unloading crane for preventing residual liquid accumulation as claimed in claim 1, characterized in that: An inlet flange (7) for connecting to a liquid output valve is provided at the inlet end of the lower portion of the liquid phase inlet flange pipe (4).

8. A liquid loading and unloading crane for preventing residual liquid accumulation as claimed in claim 2, characterized in that: A transmission mechanism (8) for driving rotation is provided at both the first rotating joint (3) and the second rotating joint (6).

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