Mounting process for large-interference-magnitude metal sealing ring of ultrahigh-pressure container

Abstract

The invention relates to a process for installing a large-interference-magnitude metal sealing ring of an ultrahigh-pressure container, which is used for installing the large-interference-magnitude metal sealing ring on the ultrahigh-pressure container and comprises the following steps of: heating part matching sections of a container barrel and an end cover in order to ensure that the large-interference-magnitude metal sealing ring is smoothly assembled in the ultrahigh-pressure container; an electric heating belt heating device is used for heating a container barrel and an end cover which are matched with the metal sealing ring, so that the temperature of the matched part of the container barrel and the end cover and the metal sealing ring is increased to a certain temperature, and the inner diameter phi D of the matched part is expanded by heating and is increased to the inner diameter phi D1; the metal sealing ring is cooled to a certain temperature through liquid nitrogen deep cooling equipment, the outer diameter phi d of the metal sealing ring is reduced to the outer diameter phi d1 due to cooling, the inner diameter phi D1 is 0.1 mm larger than the outer diameter phi d1 at the moment, it is guaranteed that the sealing ring is smoothly installed in an end cover and a cylinder body matched with the sealing ring, meanwhile, screws are tightened, and after all parts are consistent in heat conduction temperature, the sealing ring is fixed to the end cover and the cylinder body. And the interference magnitude of the metal sealing ring is recovered again, namely the installation of the interference magnitude metal sealing ring is completed, through the operation, interference assembly is changed into clearance assembly, and the metal sealing ring with the large interference magnitude can be smoothly installed in place.

Description

Technical Field

[0001] The present invention belongs to the technical field of mechanical manufacturing, and relates to an installation process for a large interference metal sealing ring of an ultra-high pressure vessel, which installs a large interference sealing metal ring onto an ultra-high pressure vessel to ensure good sealing performance of the ultra-high pressure vessel under high temperature and high pressure conditions. Background Art

[0002] At present, China is vigorously developing the deep-earth, deep-sea, aerospace and aviation industries. These researches are inseparable from high-temperature and ultra-high pressure vessels designed for various simulation environments. In the design and manufacture of these vessels, it is often necessary to assemble a metal ring with a large interference that serves as a seal into an ultra-high pressure vessel. The installation of such a large interference metal ring requires a reasonable installation process to be achieved. However, the current traditional process methods are difficult to meet the sealing requirements and have disadvantages such as difficult operation and complex processes. For example, in the patent application "A Metal Fixing Part for Pre-Installation of a Metal Ring" with the patent number CN201822162330.7, it is characterized by designing a metal fixing part including a first fixing part, a bent clamping groove part, and a second fixing part. These parts are integrally formed and connected to form a metal ring installation bracket. Compared with the prior art, it has strong operability. However, for the installation process of a metal ring with a large interference fit, it is difficult to install the interference metal ring in place by existing methods. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies existing in the prior art and provide an installation process for a large interference metal sealing ring of an ultra-high pressure vessel, so that the large interference metal sealing ring can be smoothly assembled onto the ultra-high pressure vessel, and the large interference metal sealing ring can be smoothly assembled with the cylinder body and the end cover, and ensure good sealing performance of the ultra-high pressure vessel under high temperature and high pressure conditions.

[0004] The purpose of the present invention is achieved as follows:

[0005] An installation process for a large interference metal sealing ring of an ultra-high pressure vessel. To ensure the smooth assembly of the large interference metal sealing ring into the ultra-high pressure vessel, heat the fitting sections of the cylinder body and the end cover of the vessel. Use an electric heating tape heating device to heat the cylinder body and the end cover of the vessel that cooperate with the metal sealing ring, so that the temperature of the part that cooperates with the metal sealing ring rises to a certain temperature. The inner diameter ΦD of this fitting part expands due to heat and becomes larger to a suitable size inner diameter ΦD1; use a liquid nitrogen cryogenic cooling device to cool the metal sealing ring to a certain temperature, so that its outer diameter Φd becomes smaller due to cooling to a suitable size outer diameter Φd1. At this time, it should be ensured that the inner diameter ΦD1 is 0.1 mm larger than the outer diameter Φd1 to ensure that the sealing ring can be smoothly installed into the end cover and the cylinder body that cooperate with it. At the same time, tighten the screws. After the temperatures of all parts are the same due to heat conduction, the interference of the metal sealing ring is restored again, that is, the installation of the interference metal sealing ring is completed. The specific steps are as follows:

[0006] Step 1): Use an electric heating tape heating device to heat the mating sections of the container cylinder body and the end cover that cooperate with the metal sealing ring. The heating temperature needs to be calculated according to the following formula:

[0007]

[0008] In the formula, T is the heating temperature of the parts; α is the coefficient of thermal expansion of the heated parts; d is the outer diameter of the metal seal Φd; D is the assembly mating diameter of the end cover or cylinder body ΦD; 0.1 is the required installation clearance of 0.1 mm, and -180 is the nominal cryogenic temperature of the metal sealing ring of -180°C. At this time, the heating temperature shall not be greater than the tempering temperature of the part material. If the calculated result T is less than 20, it means that the interference amount is small and there is no need to heat. The metal sealing ring can be directly cryogenically cooled and installed. If heating is required, during heating, the parts are slowly heated to the temperature T and then kept warm for 5 - 10 hours to ensure thorough heat penetration;

[0009] Step 2): Use a liquid nitrogen cryogenic equipment to cool the metal sealing ring. Cool the metal sealing ring to -180°C to -185°C by spraying or immersion, and keep it warm for 15 - 40 minutes;

[0010] Step 3): Take out the cryogenically cooled metal sealing ring from the liquid nitrogen cryogenic equipment, install it on the cylinder body, and then fix the end cover with screws. In this way, after the temperatures of all parts are the same due to heat conduction, the interference amount of the metal sealing ring is restored again, and the installation of the interference-fit metal sealing ring is completed.

[0011] The beneficial effects of the present invention are as follows:

[0012] The present invention mainly uses a liquid nitrogen cryogenic equipment to cool the metal sealing ring to shrink its outer diameter, and uses an electric heating tape to heat the cylinder body and the end cover assembled with the metal sealing ring to expand their assembly holes. Finally, the purpose that the large-interference metal sealing ring can be smoothly assembled with the cylinder body and the end cover is achieved. The present invention adopts a reasonable installation process to install the large-interference sealing metal ring on an ultra-high pressure container, ensuring good sealing performance of the container under high temperature and high pressure conditions. Description of the Drawings

[0013] Figure 1 It is a schematic diagram of an ultra-high pressure container equipped with a metal seal.

[0014] Figure 2 It is a schematic diagram of the end cover. The diameter at the place where the metal sealing ring is assembled in the figure is ΦD, and the diameter becomes ΦD1 after heating.

[0015] Figure 3 It is a schematic diagram of the metal sealing ring. The outer diameter of the metal sealing ring in the figure is Φd, and the diameter becomes Φd1 after being cooled.

[0016] Figure 4It is a schematic diagram of a cylinder. In the figure, the diameter at the place where the metal seal ring is assembled is ΦD, and after heating, the diameter becomes ΦD1.

[0017] In the figure, 1 is a screw, 2 is an end cover, 3 is a metal seal ring, 4 is a cylinder, and 5 is an air inlet hole of the container. Specific implementation method

[0018] As Figure 1 shown is a schematic diagram of the container assembly. The metal seal ring 3 is assembled together with the end cover 2 and the cylinder 4. As Figure 2 、 Figure 3 shown during assembly, the inner diameter of the mating part of the end cover 2 and the cylinder 4 that mates with the outer diameter Φd of the metal seal ring 3 is ΦD. Generally, ΦD is greater than or equal to Φ150mm. The interference of the metal seal ring: Φd - ΦD is greater than or equal to 0.3mm.

[0019] As Figure 1 shown, a mounting process for a metal seal ring with a large interference in an ultra-high pressure container. To ensure the smooth assembly of the metal seal ring with a large interference into the ultra-high pressure container, heat the mating sections of the container cylinder and the end cover parts. Use an electric heating tape heating device to heat the container cylinder and the end cover that mate with the metal seal ring, so that the mating part thereof is heated to a certain temperature. The inner diameter ΦD of this mating part expands due to heat and becomes a suitable inner diameter ΦD1; to ensure that the end time point of heating the container cylinder and the end cover is the same as the end time point of cooling the metal seal ring, for easy assembly, at 40 minutes before the end of heating, start using a liquid nitrogen cryogenic cooling device to cool the metal seal ring to a certain temperature, so that its outer diameter Φd becomes smaller to a suitable outer diameter Φd1 due to cooling. At this time, it should be ensured that the inner diameter ΦD1 is 0.1mm larger than the outer diameter Φd1, to ensure that the seal ring is smoothly installed into the end cover and the cylinder that mate with it. At the same time, tighten the screws. After the temperatures of all parts are the same due to heat conduction, the interference of the metal seal ring is restored again, that is, the installation of the interference metal seal ring is completed. The specific steps are as follows:

[0020] Step 1): Use an electric heating tape heating device to heat the mating sections of the container cylinder and the end cover that mate with the metal seal ring. The heating temperature needs to be calculated according to the following formula:

[0021]

[0022] In the formula, T is the part heating temperature; α is the thermal expansion coefficient of the heated part; d is the outer diameter Φd of the metal seal; D is the assembly mating diameter ΦD of the end cover or the cylinder; 0.1 is the required installation gap of 0.1mm, and -180 is the nominal cryogenic temperature of the metal seal ring of -180°C. At this time, the heating temperature shall not be greater than the tempering temperature of the part material. If the calculated result T is less than 20, it means that the interference is small and there is no need to heat. The metal seal ring can be directly cryogenically cooled for installation. If heating is required, during heating, the part is slowly heated to the temperature T and then held for 5 - 10 hours to ensure heat penetration;

[0023] Step 2), use a liquid nitrogen cryogenic equipment to cool the metal seal ring, and cool the metal seal ring to -180°C to -185°C by spraying or immersion, and keep it warm for 15 to 40 minutes;

[0024] Step 3), take out the cryogenically cooled metal seal ring from the liquid nitrogen cryogenic equipment, install it on the cylinder body, and then fix the end cover with screws. After the temperatures of all parts are the same due to heat conduction, the interference of the metal seal ring is restored again, and the installation of the interference metal seal ring is completed.

[0025] Example: Assemble a 6000mm long tube body with an inner assembly diameter of Φ200mm made of 35CrNi3MoV, an end cover of the same material and the same assembly diameter, and a metal seal with an outer diameter of Φ200.5mm made of 316L together, and assemble it with screws into an ultra-high pressure container for storing helium.

[0026] The specific installation process is as follows:

[0027] Step 1), to ensure that the large-interference metal seal ring can be smoothly assembled into the ultra-high pressure container, first heat the mating sections of parts such as the container cylinder body and the end cover. When there are still 40 minutes left in the heating time, cool the large-interference metal seal ring;

[0028] Step 2), use a liquid nitrogen cryogenic equipment to cool the metal seal ring, and cool the metal seal ring to -183°C by immersion, and keep it warm for 30 minutes;

[0029] Step 3), use an electric heating tape heating equipment to heat the mating sections of parts such as the container cylinder body and the end cover that cooperate with the metal seal ring. Since the thermal expansion coefficient of 35CrNi3MoV is 0.00001358 and the tempering temperature is 550°C, the outer diameter of the metal seal is Φ200.6mm; the assembly mating diameter of the end cover or the cylinder body is Φ200mm, and the heating temperature is calculated according to the following formula.

[0030]

[0031] The final heating temperature is calculated to be 80°C, which is less than the tempering temperature of 550°C. During heating, the parts need to be slowly heated to 80°C and then kept warm for 8 hours to ensure thorough heat penetration.

[0032] Step 4), take out the cryogenically cooled metal seal ring from the liquid nitrogen cryogenic equipment, install it on the cylinder body, and then fix the end cover with screws. After the temperatures of all parts are the same due to heat conduction, the interference of the metal seal ring is restored again, and the installation of the seal ring is completed.

[0033] Assemble the ultra-high pressure container for storing helium according to the above requirements. After assembly, conduct a stamping test on the container. The container has no leakage and the assembly is successful.

Claims

1. A mounting process for a metal sealing ring with a large interference fit in an ultra-high pressure vessel, characterized in that: To ensure the smooth assembly of a metal seal ring with a large interference fit into an ultra-high pressure vessel, heat the mating sections of the vessel cylinder and end cover. Use an electric heating tape heating device to heat the vessel cylinder and end cover that mate with the metal seal ring, so that the temperature of the mating part with the metal seal ring rises to a certain temperature. The inner diameter ΦD of this mating part expands due to heat and becomes larger to a suitable inner diameter ΦD1. Use a liquid nitrogen cryogenic device to cool the metal seal ring to a certain temperature, so that its outer diameter Φd becomes smaller due to cooling to a suitable outer diameter Φd1. At this time, it should be ensured that the inner diameter ΦD1 is 0.1 mm larger than the outer diameter Φd1 to ensure the smooth installation of the seal ring into the end cover and cylinder body that mate with it. At the same time, tighten the screws. After the temperatures of all parts become consistent due to heat conduction, the interference of the metal seal ring is restored again, and the installation of the interference-fit metal seal ring is completed. The specific steps are as follows: Step 1): Use an electric heating tape heating device to heat the mating sections of the vessel cylinder and end cover that mate with the metal seal ring. The heating temperature needs to be calculated according to the following formula: T＝ (d - D + 0.1) -180 Dα In the formula, T is the heating temperature of the part; α is the coefficient of thermal expansion of the heated part; d is the outer diameter Φd of the metal seal; D is the assembly mating diameter ΦD of the end cover or cylinder body; 0.1 is the required clearance of 0.1 mm for installation, and -180 is the nominal cryogenic temperature of -180°C of the metal seal ring. At this time, the heating temperature shall not be greater than the tempering temperature of the part material. If the calculated result T is less than 20, it means that the interference is small and there is no need to heat. The metal seal ring can be directly cryogenically cooled for installation. If heating is required, during heating, the part is slowly heated to the temperature T and then kept warm for 5 - 10 hours to ensure thorough heat penetration; Step 2): Use a liquid nitrogen cryogenic device to cool the metal seal ring. Cool the metal seal ring to -180°C to -185°C by spraying or immersion, and keep it warm for 15 - 40 minutes; Step 3): Take out the cryogenically cooled metal seal ring from the liquid nitrogen cryogenic device, install it on the cylinder body, and then fix the end cover with screws. In this way, after the temperatures of all parts become consistent due to heat conduction, the interference of the metal seal ring is restored again, and the installation of the interference-fit metal seal ring is completed.

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