Stepped supercharging system and method
By coordinating the stepped pressurization system with the combined valve, the problem of insufficient single pressurization of the hydraulic press was solved, enabling multiple pressurizations until the set pressure was reached, thereby improving production efficiency and reducing equipment costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-19
- Publication Date
- 2026-04-03
AI Technical Summary
Existing hydraulic presses suffer from insufficient hydraulic filling during pressurization due to the compressibility of air, resulting in insufficient capacity of the pressurizing cylinder and failure to reach the set pressure. This necessitates repressurization, leading to problems such as bulky equipment, high cost, and low efficiency.
A stepped pressurization system is adopted, which achieves stepped pressurization through the coordinated action of the pressurization unit and the combination valve. The system includes components such as pressurization cylinder, pressurization oil cylinder, and combination valve body. It uses a combination of high-pressure fluid replenishment and low-pressure fluid filling to achieve multiple pressurizations until the set pressure is reached.
This technology allows for continued pressurization without restarting if the pressure test fails to meet the target in a single test. This expands the testing range, reduces equipment costs and manufacturing difficulty, and improves production efficiency.
Smart Images
Figure CN121782220A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of equipment pressure testing, and specifically relates to a stepped pressurization system and method. Background Technology
[0002] In industrial production, pressure vessels, pipelines, valves, and other equipment must undergo pressure testing before leaving the factory to ensure their safety and compliance. Furthermore, high pressure is required for production in areas such as composite pipe molding and oil and gas well fracturing. Common pressure generation methods include air compressors and hydraulic presses. Due to the compressibility of air, air compressors are generally used in low-pressure applications, while incompressible hydraulic presses are typically used in high-pressure applications. Before pressurizing with a hydraulic press, the test object must be filled with a low-pressure liquid. However, in reality, a full liquid state is often impossible, as some air is present. Due to the compressibility of air, the amount of liquid required to pressurize using a hydraulic press increases. A single hydraulic press can only pressurize once; if the pressurizing cylinder capacity is insufficient, the test pressure will not reach the set value, and the entire pressurization process must be repeated. Currently, to solve these problems in engineering, most methods involve extending the filling time and multiplying the pressurizing cylinder capacity, resulting in excessively large equipment, increased manufacturing and operating costs, and low production efficiency. Summary of the Invention
[0003] To address the limitation of current hydraulic presses that can only perform single-stage pressurization, this invention proposes a stepped pressurization system and method.
[0004] This system utilizes a booster cylinder to drive a booster rod within the booster cylinder barrel, compressing liquid to pressurize the test element. Stepwise pressurization of the test element can be achieved through the control of a combination valve. This system significantly reduces the length of the booster cylinder and booster hydraulic cylinder, resulting in a compact structure and a wide testing range.
[0005] This invention is achieved through the following technical solution: A stepped pressurization system includes two main parts: a pressurization unit and a combined valve. The pressurization unit includes a pressurization cylinder, a pressurization oil cylinder connected to the right side of the pressurization cylinder, and a pressurization cylinder rod connected to the pressurization oil cylinder. The pressurization cylinder rod can reciprocate within the pressurization cylinder. The combined valve includes a combined valve body. A high-pressure replenishing oil cylinder is located on the upper right side of the combined valve body, and a high-pressure replenishing valve rod is connected to the high-pressure replenishing oil cylinder. A low-pressure filling oil cylinder is located on the upper left side of the combined valve body, and a low-pressure filling valve rod is connected to the low-pressure filling oil cylinder. A pressure relief oil cylinder is located on the lower left side of the combined valve body, and a pressure relief valve rod is connected to the pressure relief oil cylinder. A shut-off oil cylinder is located on the lower right side of the combined valve body, and a shut-off oil cylinder is connected to the shut-off valve rod. The combined valve body has multiple channels, including a pressurization channel, a high-pressure replenishing channel, a low-pressure inlet channel, a pressure relief channel, a pressure testing channel, and a shut-off channel, and all channels are interconnected.
[0006] Furthermore, the combined valve body is provided with a total of five liquid interfaces, namely: a pressure boosting interface, a high-pressure replenishment port, a low-pressure inlet port, a pressure testing element interface, and a residual pressure relief port. The pressure boosting interface is located on the right side of the combined valve body, the pressure testing element interface is located on the left side of the combined valve body, a low-pressure inlet port is provided vertically in the low-pressure inlet channel at the upper left of the combined valve body, and the low-pressure inlet port is opened and closed by the movement of the low-pressure filling valve rod. A high-pressure replenishment port is provided vertically in the high-pressure replenishment channel at the upper right of the combined valve body, and the high-pressure replenishment port is opened and closed by the movement of the high-pressure replenishment valve rod. A residual pressure relief port is provided vertically in the pressure relief channel at the lower left of the combined valve body, and the residual pressure relief port is opened and closed by the movement of the pressure relief valve rod.
[0007] Furthermore, the pressurization channel is connected to the pressurization cylinder via a pressurization interface; the high-pressure replenishment channel is connected to the high-pressure replenishment cylinder via a high-pressure replenishment port; the low-pressure inlet channel is connected to the low-pressure filling cylinder via a low-pressure inlet port; the pressure relief channel is connected to the pressure relief cylinder via a residual pressure relief port; the cut-off channel is connected to the cut-off cylinder; the pressure test channel is connected to both the pressure relief channel and the high-pressure replenishment channel; the pressurization channel is connected to the high-pressure replenishment channel; and the pressurization channel is connected to the pressure test channel via the cut-off channel.
[0008] Furthermore, the shut-off valve stem is disposed in the shut-off channel to control the opening and closing of the pressurization channel and the test channel.
[0009] Furthermore, the pressure testing channel is connected to a pressure testing element via a pressure testing element interface.
[0010] Furthermore, the combined valve body is made of alloy steel or stainless steel.
[0011] Furthermore, the present invention also provides a stepped turbocharging method, which is based on any of the stepped turbocharging systems described above, and the specific steps are as follows: S1: Use the low-pressure filling cylinder to lower the low-pressure filling valve rod to close the low-pressure inlet. Use the boosting cylinder to pull the boosting cylinder rod to the far right. Use the high-pressure replenishing cylinder to lower the high-pressure replenishing valve rod to close the high-pressure replenishing port. Use the pressure relief cylinder to push out the pressure relief valve rod to close the residual pressure relief port. Use the shut-off cylinder to pull back the shut-off valve rod to open the shut-off channel and connect the pressure testing element. S2: Use the low-pressure filling cylinder to pull back the low-pressure filling valve rod, open the low-pressure inlet, and the low-pressure liquid basically fills the entire test element, the combined valve body channel and the booster cylinder. Use the low-pressure filling cylinder to lower the low-pressure filling valve rod, close the low-pressure inlet, and use the booster cylinder to push the booster cylinder rod to the left inside the booster cylinder to start boosting. S3: When the pressure reaches the set value, stop pressurizing and maintain the pressure. Then, use the pressurizing cylinder to pull the pressurizing cylinder rod back to the right inside the pressurizing cylinder. Next, use the pressure relief cylinder to pull back the pressure relief valve rod to open the residual pressure relief port, thus completing the pressure relief and the entire test is completed. S4: If the pressure in the pressure testing element does not reach the set value after step S2 is completed, use the shut-off cylinder to push the shut-off valve rod upward to isolate the high pressure. Then, use the high-pressure replenishment cylinder to pull back the high-pressure replenishment valve rod to open the high-pressure replenishment port. Next, use the booster cylinder to pull the booster cylinder rod back to the right inside the booster cylinder to replenish the booster cylinder. After replenishment, use the high-pressure replenishment cylinder to lower the high-pressure replenishment valve rod to close the high-pressure replenishment port. Then, use the shut-off cylinder to pull the shut-off valve rod downward to open the booster channel. Use the booster cylinder to push the booster cylinder rod to the left inside the booster cylinder to continue boosting the pressure. Repeat the above process until the pressure reaches the set value. After the pressure is maintained, the final pressure relief process is the same as in S3.
[0012] The beneficial effects of this invention are as follows: This invention combines a pressure boosting unit and a combined valve, wherein the combined valve body includes components such as a high-pressure replenishing cylinder, a low-pressure filling cylinder, a shut-off cylinder, and a pressure relief cylinder. Through the coordinated action of these cylinders, a stepped pressure boosting effect can be achieved on the testing element. Compared to traditional hydraulic presses that can only perform single-stage pressure boosting, this invention does not require starting from scratch if a single boosting fails to reach the target pressure; it simply continues boosting based on the previous boosting by controlling the combined valve. This invention has a wide testing range, broad application scope, compact structure, and can significantly reduce manufacturing and production costs, possessing immense socio-economic value. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the structure of a stepped booster system according to the present invention; In the diagram: 1. Booster cylinder; 2. Booster cylinder rod; 3. Booster cylinder barrel; 4. Combined valve body; 5. High-pressure replenishing valve rod; 6. High-pressure replenishing cylinder; 7. Low-pressure filling cylinder; 8. Low-pressure filling valve rod; 9. Pressure relief valve rod; 10. Pressure relief cylinder; 11. Shut-off cylinder; 12. Shut-off valve rod; 13. Pressure testing element; 4-1. Pressure boosting interface; 4-2. High-pressure replenishment port; 4-3. Low-pressure inlet port; 4-4. Pressure testing element interface; 4-5. Residual pressure relief port; 4-6. Pressure boosting channel; 4-7. High-pressure replenishment channel; 4-8. Low-pressure inlet channel; 4-9. Pressure relief channel; 4-10. Pressure testing channel; 4-11. Cut-off channel. Detailed Implementation
[0014] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. However, the scope of protection of the present invention is not limited to these embodiments. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0015] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The invention will be further described in detail below with reference to the accompanying drawings.
[0016] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0017] Example like Figure 1As shown, a stepped booster system includes two main parts: a booster unit and a combination valve. The booster unit includes a booster cylinder 3, with a booster oil cylinder 1 connected to the right side of the booster cylinder 3. A booster cylinder rod 2 is connected to the booster oil cylinder 1, and the booster cylinder rod 2 can reciprocate within the booster cylinder 3. The combination valve includes a combination valve body 4, with a high-pressure replenishing oil cylinder 6 located on the upper right side of the combination valve body 4. The high-pressure replenishing oil cylinder 6 is connected to a high-pressure replenishing valve rod 5, and a low-pressure filling oil cylinder 7 is located on the upper left side of the combination valve body 4. The filling cylinder 7 is connected to a low-pressure filling valve stem 8. The lower left of the combined valve body 4 is provided with a pressure relief cylinder 10, which is connected to a pressure relief valve stem 9. The lower right of the combined valve body 4 is provided with a shut-off cylinder 11, which is connected to a shut-off valve stem 12. The combined valve body 4 is provided with multiple channels, including a pressurization channel 4-6, a high-pressure replenishment channel 4-7, a low-pressure inlet channel 4-8, a pressure relief channel 4-9, a pressure testing channel 4-10, and a shut-off channel 4-11, and all channels are interconnected.
[0018] Furthermore, the combined valve body 4 is provided with five liquid interfaces, namely: a pressure boosting interface 4-1, a high-pressure replenishment port 4-2, a low-pressure inlet port 4-3, a pressure testing element interface 4-4, and a residual pressure relief port 4-5. The pressure boosting interface 4-1 is located on the right side of the combined valve body 4, the pressure testing element interface 4-4 is located on the left side of the combined valve body 4, and the low-pressure inlet port 4-3 is located vertically to the low-pressure inlet channel 4-8 on the upper left side of the combined valve body 4. The low-pressure inlet port 4-3 is opened and closed by the movement of the low-pressure filling valve rod 8. The high-pressure replenishment port 4-2 is located vertically to the high-pressure replenishment channel 4-7 on the upper right side of the combined valve body 4. The high-pressure replenishment port 4-2 is opened and closed by the movement of the high-pressure replenishment valve rod 5. The residual pressure relief port 4-5 is located vertically to the pressure relief channel 4-9 on the lower left side of the combined valve body 4. The residual pressure relief port 4-5 is opened and closed by the movement of the pressure relief valve rod 9.
[0019] Furthermore, the pressurization channel 4-6 is connected to the pressurization cylinder 3 via the pressurization port 4-1; the high-pressure replenishment channel 4-7 is connected to the high-pressure replenishment cylinder 6 via the high-pressure replenishment port 4-2; the low-pressure inlet channel 4-8 is connected to the low-pressure filling cylinder 7 via the low-pressure inlet port 4-3; the pressure relief channel 4-9 is connected to the pressure relief cylinder 10 via the residual pressure relief port 4-5; the cut-off channel 4-11 is connected to the cut-off cylinder 11; the pressure test channel 4-10 is connected to both the pressure relief channel 4-9 and the high-pressure replenishment channel 4-7; the pressurization channel 4-6 is connected to the high-pressure replenishment channel 4-7; and the pressurization channel 4-6 is connected to the pressure test channel 4-10 via the cut-off channel 4-11.
[0020] Furthermore, the shut-off valve stem 12 is disposed in the shut-off channel 4-11 and is used to control the opening and closing of the pressurization channel 4-6 and the test pressure channel 4-10.
[0021] Furthermore, the pressure testing channel is connected to the pressure testing element 13 via the pressure testing element interface 4-4.
[0022] Preferably, the combined valve body 4 is made of alloy steel or stainless steel.
[0023] Preferably, the alloy steel is a high-strength alloy steel. Preferably, the high-strength alloy steel is 42CrMo high-strength alloy steel. This high-strength alloy steel, after quenching and tempering, possesses excellent comprehensive mechanical properties, can withstand the system's highest working pressure (e.g., 100 MPa), and exhibits good fatigue resistance.
[0024] Furthermore, the pressure value borne by the pressure testing element 13 can be read from the pressure sensor built into the pressure testing element 13, or a pressure sensor can be installed at the pressure testing element interface 4-4.
[0025] Based on the aforementioned stepped supercharging system, this invention also provides a stepped supercharging method, the specific steps of which are as follows: S1: Use the low-pressure filling cylinder 7 to lower the low-pressure filling valve rod 8 to close the low-pressure inlet 4-3. Use the boosting cylinder 1 to pull the boosting cylinder rod 2 to the far right. Use the high-pressure replenishing cylinder 6 to lower the high-pressure replenishing valve rod 5 to close the high-pressure replenishing port 4-2. Use the pressure relief cylinder 10 to push out the pressure relief valve rod 9 to close the residual pressure relief port 4-5. Use the shut-off cylinder 11 to pull back the shut-off valve rod 12 to open the shut-off channel and connect the test pressure element 13. S2: Use the low-pressure filling cylinder 7 to pull back the low-pressure filling valve rod 8, open the low-pressure inlet port 4-3, and the low-pressure liquid basically fills the entire test element 13, the passage of the combined valve body 4 and the booster cylinder 3. After the low-pressure liquid is basically filled, use the low-pressure filling cylinder 7 to drop the low-pressure filling valve rod 8, close the low-pressure inlet port 4-3, and use the booster cylinder 1 to push the booster cylinder rod 2 to the left in the booster cylinder 3 to start boosting. S3: When the pressure reaches the set value (which can be monitored by the pressure sensor), stop pressurization and maintain pressure. Then, use the pressurization cylinder 1 to pull the pressurization cylinder rod 2 back to the right inside the pressurization cylinder 3. Next, use the pressure relief cylinder 10 to pull back the pressure relief valve rod 9 to open the residual pressure relief port 4-5, thus completing the pressure relief. The entire test is now complete. S4: If, after step S2, there is a possibility of micro-leakage, or the low-pressure liquid fails to fill the cylinder when it flows in (e.g., air bubbles are present), resulting in the pressure in the pressure testing element 13 not reaching the set value even when the pressure boosting cylinder 3 reaches the top left, then the shut-off cylinder 11 pushes the shut-off valve rod 12 upward to isolate the high pressure. After that, the high-pressure replenishing cylinder 6 pulls back the high-pressure replenishing valve rod 5 to open the high-pressure replenishing port 4-2. Then, the boosting cylinder 1 pulls the boosting cylinder rod 2 back to the right inside the boosting cylinder 3 to replenish the pressure boosting cylinder 3. After replenishing the liquid, the high-pressure replenishing cylinder 6 lowers the high-pressure replenishing valve rod 5 to close the high-pressure replenishing port 4-2. Next, the shut-off cylinder 11 pulls the shut-off valve rod 12 downward to open the boosting channel. The boosting cylinder 1 pushes the boosting cylinder rod 2 to the left inside the boosting cylinder 3 to continue boosting the pressure. The above process is repeated until the pressure reaches the set value. After the pressure is maintained, the final depressurization process is the same as in S3.
[0026] This system can perform stepped pressurization of the pressure testing element 13 through the coordinated operation of the pressurization unit and the combination valve. If a single pressurization fails to reach the target pressure, the system does not need to start pressurization from scratch; it can simply continue pressurization based on the previous pressurization by controlling the valve assembly. The system of this invention features a wide testing range, broad application scope, compact structure, and low manufacturing and production costs.
[0027] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A stepped booster system, characterized in that: The system comprises two main parts: a booster unit and a combination valve. The booster unit includes a booster cylinder (3), with a booster oil cylinder (1) connected to the right side of the booster cylinder (3). A booster cylinder rod (2) is connected to the booster oil cylinder (1), and the booster cylinder rod (2) can reciprocate within the booster cylinder (3). The combination valve includes a combination valve body (4), with a high-pressure replenishing oil cylinder (6) located on the upper right side of the combination valve body (4). The high-pressure replenishing oil cylinder (6) is connected to a high-pressure replenishing valve rod (5). A low-pressure filling oil cylinder (7) is located on the upper left side of the combination valve body (4). The low-pressure filling oil cylinder (7) is connected to a... The combined valve body (4) has a low-pressure filling valve stem (8), a pressure relief cylinder (10) is provided on the lower left side of the combined valve body (4), the pressure relief cylinder (10) is connected to a pressure relief valve stem (9), and a shut-off cylinder (11) is provided on the lower right side of the combined valve body (4), the shut-off cylinder (11) is connected to a shut-off valve stem (12). The combined valve body (4) has multiple channels, including a pressure boosting channel (4-6), a high-pressure replenishment channel (4-7), a low-pressure inlet channel (4-8), a pressure relief channel (4-9), a pressure testing channel (4-10), and a shut-off channel (4-11), and all channels are interconnected.
2. The stepped booster system according to claim 1, characterized in that: The combined valve body (4) is provided with a total of five liquid interfaces, namely: a pressure boosting interface (4-1), a high-pressure replenishment port (4-2), a low-pressure inlet port (4-3), a pressure testing element interface (4-4), and a residual pressure relief port (4-5). The pressure boosting interface (4-1) is located on the right side of the combined valve body (4), the pressure testing element interface (4-4) is located on the left side of the combined valve body (4), and the low-pressure inlet port (4-3) is provided vertically to the low-pressure inlet channel (4-8) on the upper left of the combined valve body (4). The low-pressure inlet (4-3) is opened and closed by the movement of the low-pressure filling valve rod (8). The high-pressure filling port (4-2) is provided vertically in the high-pressure filling channel (4-7) on the upper right of the combined valve body (4). The high-pressure filling port (4-2) is opened and closed by the movement of the high-pressure filling valve rod (5). The residual pressure relief port (4-5) is provided vertically in the pressure relief channel (4-9) on the lower left of the combined valve body (4). The residual pressure relief port (4-5) is opened and closed by the movement of the pressure relief valve rod (9).
3. The stepped booster system according to claim 2, characterized in that: The pressurization channel (4-6) is connected to the pressurization cylinder (3) through the pressurization port (4-1), the high-pressure replenishment channel (4-7) is connected to the high-pressure replenishment cylinder (6) through the high-pressure replenishment port (4-2), the low-pressure inlet channel (4-8) is connected to the low-pressure filling cylinder (7) through the low-pressure inlet port (4-3), the pressure relief channel (4-9) is connected to the pressure relief cylinder (10) through the residual pressure relief port (4-5), the cut-off channel (4-11) is connected to the cut-off cylinder (11), the test pressure channel (4-10) is connected to the pressure relief channel (4-9) and the high-pressure replenishment channel (4-7) respectively, the pressurization channel (4-6) is connected to the high-pressure replenishment channel (4-7), and the pressurization channel (4-6) is connected to the test pressure channel (4-10) through the cut-off channel (4-11).
4. The stepped booster system according to claim 3, characterized in that: The shut-off valve stem (12) is located in the shut-off channel (4-11) and is used to control the opening and closing of the pressure boosting channel (4-6) and the pressure testing channel (4-10).
5. A stepped booster system according to claim 2, characterized in that: The pressure test channel is connected to the pressure test element (13) through the pressure test element interface (4-4).
6. A stepped booster system according to claim 2, characterized in that: The combined valve body (4) is made of alloy steel or stainless steel.
7. A stepped turbocharging method, based on the stepped turbocharging system according to any one of claims 2-6, characterized in that: The specific steps are as follows: S1: Use the low-pressure filling cylinder (7) to lower the low-pressure filling valve rod (8) to close the low-pressure inlet (4-3), use the boosting cylinder (1) to pull the boosting cylinder rod (2) to the far right, use the high-pressure replenishing cylinder (6) to lower the high-pressure replenishing valve rod (5) to close the high-pressure replenishing port (4-2), use the pressure relief cylinder (10) to push out the pressure relief valve rod (9) to close the residual pressure relief port (4-5), use the stop cylinder (11) to pull back the stop valve rod (12) to open the stop channel, and connect the pressure test element (13); S2: Use the low-pressure filling cylinder (7) to pull back the low-pressure filling valve rod (8), open the low-pressure inlet (4-3), and the low-pressure liquid basically fills the entire pressure test element (13), the combined valve body (4) channel and the booster cylinder (3). Use the low-pressure filling cylinder (7) to drop the low-pressure filling valve rod (8), close the low-pressure inlet (4-3), and use the booster cylinder (1) to push the booster cylinder rod (2) to the left in the booster cylinder (3) to start boosting. S3: When the pressure reaches the set value, stop pressurizing and holding the pressure. Then, use the pressurizing cylinder (1) to pull the pressurizing cylinder rod (2) back to the right in the pressurizing cylinder barrel (3). Then, use the pressure relief cylinder (10) to pull back the pressure relief valve rod (9) to open the residual pressure relief port (4-5) and complete the pressure relief. The entire test is completed. S4: If the pressure in the pressure testing element (13) does not reach the set value after step S2 is completed, use the shut-off cylinder (11) to push the shut-off valve rod (12) upward to isolate the high pressure. Then use the high pressure replenishing cylinder (6) to pull back the high pressure replenishing valve rod (5) to open the high pressure replenishing port (4-2). Then use the boosting cylinder (1) to pull the boosting cylinder rod (2) to the right in the boosting cylinder (3) to replenish the boosting cylinder (3). After replenishing the liquid, use the high pressure replenishing cylinder (6) to drop the high pressure replenishing valve rod (5) to close the high pressure replenishing port (4-2). Then use the shut-off cylinder (11) to pull the shut-off valve rod (12) downward to open the boosting channel. Use the boosting cylinder (1) to push the boosting cylinder rod (2) to the left in the boosting cylinder (3) to continue boosting the pressure. Repeat the above process until the pressure reaches the set value. After the pressure is maintained, the final pressure relief process is the same as in S3.