Bypass vent device ramming method

Abstract

The application discloses a bypass discharge device pressing method, which comprises the following steps: assembling a steam inlet flange, a first-stage cylinder and a first-stage pressing blanking plate, selecting a pressure test pressure according to a first-stage bypass discharge design pressure, processing a reserved first-stage cylinder length to a first-stage cylinder design size after completing the pressure test, assembling the first-stage cylinder with a first-stage cone and a first-stage blanking plate, and completing the pressing and manufacturing of the first-stage bypass discharge; assembling the first-stage bypass discharge with a second-stage end plate, a second-stage cylinder and a second-stage pressing blanking plate, selecting a pressure test pressure according to a second-stage bypass discharge design pressure, processing a reserved second-stage cylinder length to a second-stage cylinder design size after completing the pressure test, assembling the second-stage cylinder with a second-stage cone and a second-stage blanking plate, and completing the pressing and manufacturing of the second-stage bypass discharge; and pressing and assembling the bypass discharge device step by step according to the pressing and manufacturing method of the second-stage bypass discharge to the last stage. The application realizes the lightweight and reliability design and manufacturing of the bypass discharge device.

Description

Technical Field

[0001] This invention belongs to the technical field of pressure testing process for bypass discharge devices, and relates to a pressure testing method for bypass discharge devices. Background Technology

[0002] As a critical piece of equipment for marine accident and emergency discharge, the bypass discharge device's main function is to participate in the load regulation of the steam system and prevent overpressure of the main steam and reheat steam. If it does not meet the unit's requirements for steam load adaptability, it will seriously threaten the safe and economical operation of the unit, leading to unit shutdown or even accidents; therefore, it must be given sufficient attention. For this reason, the bypass discharge device design adopts multi-stage pressure reduction technology to adapt to the operating requirements of variable loads. To ensure the reliability of the bypass discharge device, a pressure test is required during the manufacturing process to verify whether the strength of the equipment meets the operational requirements. According to the design scheme of step-by-step pressure reduction for bypass discharge, due to the specific size limitations of the equipment during actual manufacturing, it is not possible to weld the cone and cylinder together before drilling holes. It is necessary to pre-drill holes in the plate, roll it into a cone, and then weld it to the cylinder, or to use a forging to machine the cone separately, drill holes, and then weld it to the cylinder. If the pressure test pressure is selected based on the design pressure of the first stage of bypass discharge, it will result in thicker walls for subsequent stages of equipment, leading to larger equipment sizes and material waste. Using the outlet pressure of the last stage of the bypass discharge as the design pressure for the pressure test would result in the strength of the earlier stages failing to meet operational requirements. Therefore, to ensure the lightweight and reliability of the bypass discharge device, it is necessary to pressurize each stage of the device before reassembly. Furthermore, the actual structure of the bypass discharge device is quite complex, and currently there is no mature pressure testing process specifically designed for bypass discharge devices in engineering. Summary of the Invention

[0003] In view of the above-mentioned prior art, the technical problem to be solved by the present invention is to provide a novel pressure testing method for bypass discharge devices, which, in combination with actual engineering requirements, completes the pressure resistance test of the bypass discharge device.

[0004] To solve the above-mentioned technical problems, the present invention provides a bypass discharge device pressurization method, comprising:

[0005] Assemble the steam inlet flange, Stage I cylinder, and Stage I pressure-pressurizing plug. Select the pressure test pressure according to the design pressure of Stage I bypass discharge. Connect the steam inlet flange to the pressure-pressurizing system pipeline for pressure testing. After passing the pressure test, process the reserved length of Stage I cylinder to the design size of Stage I cylinder, and then assemble it with Stage I cone and Stage I plug to complete the pressure testing and manufacturing of Stage I bypass discharge. Assemble the Stage I bypass discharge with Stage II end plate, Stage II cylinder, and Stage II pressure-pressurizing plug. Select the pressure test pressure according to the design pressure of Stage II bypass discharge. Connect the steam inlet flange to the pressure-pressurizing system pipeline for pressure testing. After passing the pressure test, process the reserved length of Stage II cylinder to the design size of Stage II cylinder, and then assemble it with Stage II cone and Stage II plug to complete the pressure testing and manufacturing of Stage II bypass discharge. Follow the pressure testing and manufacturing method of Stage II bypass discharge to perform pressure testing and assembly stage by stage until the last stage bypass.

[0006] Furthermore, each stage of the cylinder is designed with a length sufficient to meet the sealing process requirements. This length is three times the thickness of the cylinder and not less than 100 mm.

[0007] The beneficial effects of this invention are as follows: By optimizing the design of the pressure testing fixtures and process of the bypass emission device and formulating a reasonable pressure testing process, this invention can more efficiently complete the step-by-step pressure resistance test of the bypass emission device, verify the structural strength of the equipment, and achieve lightweight and reliable design and manufacturing of the bypass emission device. Compared with the prior art:

[0008] (1) The pressure testing tooling of this pressure testing process is mainly based on equipment parts, which can realize the pressure test of the bypass discharge device more efficiently.

[0009] (2) This pressure testing process can be applied to the step-by-step pressure testing of multi-stage bypass discharge devices.

[0010] (3) This pressure testing process can select the length of each bypass discharge cylinder to meet the sealing process requirements. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the bypass emission device design;

[0012] Figure 2 This is a schematic diagram of the Level I bypass emission pressurization;

[0013] Figure 3 This is a schematic diagram of the Level II bypass emission pressure test;

[0014] Figure 4 This is a schematic diagram of the Level III bypass discharge pressure test. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0016] This invention discloses a novel pressure testing process for a bypass emission device. Considering the requirements for lightweight and reliable equipment, the bypass emission device undergoes a step-by-step pressure test. The process is illustrated using a three-stage bypass emission device as an example, with subsequent stages following the same principle. Each stage of the bypass emission cylinder is pre-lengthened to meet sealing requirements during material preparation. First, the steam inlet flange, the first-stage cylinder, and the first-stage pressure testing plate are assembled. The pressure test pressure is selected according to the design pressure of the first-stage bypass emission. The steam inlet flange is then connected to the pressure testing system pipeline for a pressure test. After the pressure test is passed, the pre-lengthened first-stage cylinder is machined to the design dimensions of the first-stage cylinder. Finally, it is assembled with the first-stage cone and the first-stage blocking plate, completing the pressure testing and manufacturing of the first-stage bypass emission. The first-stage bypass discharge is assembled with the second-stage end plate, second-stage cylinder, and second-stage pressure-pressurizing plug. The pressure test pressure is selected according to the design pressure of the second-stage bypass discharge. The steam inlet flange is connected to the pressure-pressurizing system pipeline for a pressure test. After passing the pressure test, the reserved length of the second-stage cylinder is machined to the design dimensions of the second-stage cylinder. Then, it is assembled with the second-stage cone and second-stage plug to complete the pressure testing and manufacturing of the second-stage bypass discharge. The second-stage bypass discharge is then assembled with the third-stage end plate, third-stage cylinder, and third-stage pressure-pressurizing plug. The pressure test pressure is selected according to the design pressure of the third-stage bypass discharge. The steam inlet flange is connected to the pressure-pressurizing system pipeline for a pressure test. After passing the pressure test, the reserved length of the third-stage cylinder is machined to the design dimensions of the third-stage cylinder. Then, it is assembled with the third-stage cone and third-stage plug to complete the pressure testing and manufacturing of the third-stage bypass discharge.

[0017] When cutting each stage of the cylinder, the length reserved to meet the sealing process should be greater than 3 times the thickness of the cylinder, and not less than 100mm.

[0018] The specific implementation method is illustrated using a three-stage bypass emission device as an example. A schematic diagram of the bypass emission device design is shown below. Figure 1 As shown, 1-steam inlet flange, 2-Class I cylinder, 3-Class II end plate, 4-Class I cone, 5-Class I blocking plate, 6-Class II cylinder, 7-Class III end plate, 8-Class III cylinder, 9-Class II cone, 10-Class II blocking plate, 11-Class III cone, 12-Class III blocking plate.

[0019] Step 1: Stage I bypass discharge pressurization Figure 2As shown, 1-Stage I cylinder and 2-Stage I pressure-pressurizing plug are used. When cutting the Stage I cylinder, a length L2 is reserved to meet the sealing process requirements. L2 is selected to be greater than three times the thickness h1 of the Stage I cylinder, and not less than 100mm. Then, the steam inlet flange, Stage I cylinder, and Stage I pressure-pressurizing plug are assembled. The pressure test pressure is selected according to the design pressure of the Stage I bypass discharge. The steam inlet flange is connected to the pressure-pressurizing system pipeline for a pressure test. After the pressure test is passed, the reserved length of the Stage I cylinder is machined to the design dimension L1 of the Stage I cylinder, and then assembled with the Stage I cone and Stage I plug to complete the pressure testing and manufacturing of the Stage I bypass discharge.

[0020] Step 2: Level II bypass discharge pressurization Figure 3 As shown, the Class I bypass discharge consists of a Class II cylinder and a Class II pressure-pressurizing plug plate. When cutting the Class II cylinder, a length L4 is reserved to meet the sealing process requirements. L4 is selected to be greater than three times the thickness h2 of the Class II cylinder, and not less than 100mm. The Class I bypass discharge is assembled with the Class II end plate, Class II cylinder, and Class II pressure-pressurizing plug plate. The pressure test pressure is selected according to the design pressure of the Class II bypass discharge. The steam inlet flange is connected to the pressure-pressurizing system pipeline for a pressure test. After the pressure test is passed, the reserved length of the Class II cylinder is machined to the design size L3 of the Class II cylinder, and then assembled with the Class II cone and Class II plug plate to complete the pressure testing and manufacturing of the Class II bypass discharge.

[0021] Step 3: Level III bypass discharge pressurization Figure 4 As shown, when cutting the Class III cylinder (1-III) and the Class III pressure-pressurizing plug plate (2-III), a length L6 is reserved to meet the sealing process requirements. L6 is selected to be greater than three times the thickness h3 of the Class III cylinder, and not less than 100mm. The Class II bypass discharge is assembled with the Class III end plate, Class III cylinder, and Class III pressure-pressurizing plug plate. The pressure test pressure is selected according to the design pressure of the Class III bypass discharge. The steam inlet flange is connected to the pressure-pressurizing system pipeline for a pressure test. After the pressure test is passed, the reserved length of the Class III cylinder is machined to the design size L6 of the Class III cylinder, and then assembled with the Class III cone and Class III plug plate to complete the pressure testing and manufacturing of the Class III bypass discharge.

Claims

1. A bypass vent apparatus ramming method characterized by, include: Assemble the steam inlet flange, the first-stage cylinder, and the first-stage pressure-pressurizing plug. Select the pressure test pressure according to the design pressure of the first-stage bypass discharge. Connect the steam inlet flange to the pressure-pressurizing system pipeline and conduct a pressure test. After the pressure test is passed, process the reserved length of the first-stage cylinder to the design size of the first-stage cylinder. Then assemble it with the first-stage cone and the first-stage plug to complete the pressure testing and manufacturing of the first-stage bypass discharge. Assemble the first-stage bypass discharge with the second-stage end plate, second-stage cylinder, and second-stage pressure-pressurizing plug. Select the pressure test pressure according to the design pressure of the second-stage bypass discharge. Connect the steam inlet flange to the pressure-pressurizing system pipeline for pressure testing. After the pressure test is passed, process the reserved length of the second-stage cylinder to the design size of the second-stage cylinder. Then assemble it with the second-stage cone and second-stage plug to complete the pressure testing and manufacturing of the second-stage bypass discharge. Follow the pressure testing and manufacturing method of the second-stage bypass discharge to perform pressure testing and assembly step by step until the last stage of the bypass discharge device is reached.

2. A method of pressurizing a bypass vent device according to claim 1, wherein: When cutting each stage of the cylinder, a length sufficient to meet the sealing process is reserved. The length is three times the thickness of the cylinder at that stage, and not less than 100 mm.

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