Flexible chain type heat preservation device for nuclear grade pipe segment welding

Abstract

A flexible chain type heat preservation device for nuclear grade pipe section welding, which comprises a plurality of long strip-shaped heat conducting blocks, the plurality of long strip-shaped heat conducting blocks are placed transversely and arranged in a row from top to bottom, the end portions of two adjacent long strip-shaped heat conducting blocks are sequentially connected through flexible hinges to form a complete heat conducting plate, a locking buckle is fixed on the flexible hinge at the free end of the heat conducting plate, and the two free ends of the heat conducting plate are locked through the locking buckle; a heating coil and a temperature measuring probe are embedded in the heat conducting plate, a controller controls the heating coil, and the temperature measuring probe transmits signals to the controller through a control line. The present application has the advantages of light weight, suitable for single person to hold and move, suitable for the whole welding process of preheating / heat preservation, welding temperature control and post-welding slow cooling, flexible positioning during the welding process, good practicability, economic convenience, strong process and the like.

Description

Technical Field

[0001] This invention belongs to the field of marine nuclear power pipeline design, specifically relating to a flexible chain insulation device for welding nuclear-grade pipe sections. Background Technology

[0002] Currently, the shipbuilding industry has high-performance requirements for nuclear power pipelines, cryogenic piping systems of LNG / LPG or CO2 liquefied gas transport ships, corrosion-resistant seawater pipelines, and high-temperature and high-pressure steam pipes, including radiation aging resistance, low-temperature crack resistance, resistance to high potential difference corrosion of dissimilar media, and resistance to high-temperature stress fatigue.

[0003] To ensure the quality and long-term reliability of the weld formation, the main measures of preheating / insulation, welding temperature control, and slow cooling after welding must be adopted. This is to control the level of internal stress in the weld caused by the cooling of the deposited metal during the welding process, thereby suppressing the tendency of welding cracks, including hydrogen-induced cracks, and ensuring the quality of weld formation (after cooling).

[0004] When using the above measures, the pipe fittings are generally heated to a certain temperature value within the range of 100℃~350℃ (with a deviation or redundancy of 50℃) by means of flame baking, electric heating pads (ceramic) / electric heating blankets (industrial use), or heating in a heating furnace (gas or electric furnace) before welding. This is called preheating.

[0005] After preheating and removal of the heating source, the preheated pipe fittings will be in a cooling process in the air, in a confined space, or covered with insulating / heat-insulating materials without a heating source. In order to ensure that the heated pipe fittings do not cool down too quickly and fall below the temperature limit specified by the welding process after preheating (the heat transfer mode of cooling is mainly air convection and thermal radiation), it is necessary to use appropriate devices to slow down the degree and rate of cooling of the heated pipe fittings as much as possible.

[0006] Meanwhile, some pipe fittings, due to differences in materials, specifications, welding processes, and surrounding environment (heat dissipation), cannot rely on the welding heat generated during the welding process to maintain a stable temperature (not falling below the temperature limit specified in the welding process) after welding begins without insulation. They also require corresponding devices, which is called welding temperature control. Compared with the aforementioned insulation, the size of the welding temperature control device must provide adequate space for welding operations while ensuring temperature control (avoiding excessively rapid cooling). In other words, larger sizes are beneficial for welding operations but not for temperature control and insulation, while smaller sizes are beneficial for ensuring temperature control but not for welding operations.

[0007] Since it is necessary to use appropriate devices during preheating / insulation and welding temperature control, it is also effective and necessary to adopt such devices for post-weld slow cooling. Summary of the Invention

[0008] To address the aforementioned problems, this invention provides a flexible chain-type heat preservation device for welding nuclear-grade pipe sections. The aim is to control the temperature of the pipe being welded within the preheated range specified in the welding process, thereby improving stress concentration, reducing crack initiation tendency, and ensuring weld quality. The technical solution adopted is as follows: A flexible chain-type heat insulation device for welding nuclear-grade pipe sections has multiple elongated heat-conducting blocks. These blocks are placed horizontally and arranged in a row from top to bottom. The ends of two adjacent elongated heat-conducting blocks are connected sequentially by flexible hinges to form a complete heat-conducting plate. A locking buckle is fixed on the flexible hinge at the free end of the heat-conducting plate. After the two free ends of the heat-conducting plate are joined together, they are locked by the locking buckle.

[0009] The heat-conducting plate contains a heating coil and a temperature probe. The controller controls the heating coil, and the temperature probe transmits signals to the controller.

[0010] Furthermore, in the aforementioned flexible chain insulation device for welding nuclear-grade pipe sections, the heating coil is located inside the heat-conducting block and arranged in an S-shaped path from one end of the heat-conducting block to the other.

[0011] Furthermore, in the aforementioned flexible chain insulation device for welding nuclear-grade pipe sections, the heat-conducting plate is adsorbed onto the inner or outer surface of the nuclear-grade pipe, and after circling the nuclear-grade pipe once, it is locked in place by a locking buckle to form a cylindrical shape.

[0012] Furthermore, the aforementioned flexible chain insulation device for welding nuclear-grade pipe sections further includes a controller connected to a power source.

[0013] Furthermore, in the aforementioned flexible chain insulation device for welding nuclear-grade pipe sections, two heat-conducting plates are located on both sides of the weld seam of the nuclear-grade pipe section.

[0014] Furthermore, in the aforementioned flexible chain insulation device for welding nuclear-grade pipe sections, the temperature probe transmits signals to the controller via a control line.

[0015] The beneficial effects of this invention are as follows: 1. This invention provides a flexible chain insulation device for welding nuclear-grade pipe sections. This device has a heating function, capable of heating the pipe to a preheating temperature and maintaining the pipe's temperature accurately within the range specified in the welding process. Existing insulation or temperature control methods mostly use insulating materials to cover the pipe, lacking a heating function and thus operating in a cooling state, easily falling below the preheating temperature range specified in the welding process.

[0016] 2. This invention discloses a flexible chain-type heat preservation device for welding nuclear-grade pipe sections. It adapts to the size of the pipe by splicing hinges of varying lengths. Heat-conducting blocks containing heating coils are tightly arranged and adhered to the inner and outer walls of the pipe, uniformly heating the pipe and ensuring a consistent temperature throughout. Existing methods for heating pipes typically involve flame heating, electric heating elements, electric blankets, or furnaces. The first three methods suffer from uneven temperature distribution throughout the pipe after heating, while furnaces limit the pipe's volume. 3. The flexible chain insulation device for welding nuclear-grade pipe sections of the present invention can accurately measure the temperature of various parts of the pipe through the temperature measuring head on each heat-conducting block. Existing temperature measurement methods include remote infrared temperature measurement and contact resistance temperature measurement, which measure the temperature of a certain point of the pipe and cannot accurately and comprehensively reflect the overall temperature change during pipe welding. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the present invention.

[0018] Figure 2 This is a schematic diagram illustrating the use of the present invention; Among them, 1-controller, 2-power supply, 3-heat conducting block, 4-heating coil, 5-temperature probe, 6-control line, 7-power line, 8-flexible hinge. Detailed Implementation

[0019] The invention will be further described with reference to the accompanying drawings.

[0020] A flexible chain insulation device for welding nuclear-grade pipe sections, such as Figure 1 As shown, it includes a heat-conducting plate for heating, heat preservation, and slow cooling of the tube, and multiple long strip-shaped heat-conducting blocks. The multiple long strip-shaped heat-conducting blocks are placed horizontally and arranged in a row from top to bottom. The ends of two adjacent long strip-shaped heat-conducting blocks are connected sequentially by flexible hinges to form a complete heat-conducting plate. A locking buckle is fixed on the flexible hinge at the free end of the heat-conducting plate. After the two free ends of the heat-conducting plate are joined together, they are locked by the locking buckle.

[0021] A heating coil and a temperature probe are embedded inside the heat-conducting plate. The controller controls the heating coil, and the temperature probe transmits signals to the controller via a control line. The heating coil is located inside the heat-conducting block and is arranged in an S-shape from one end to the other. The heat-conducting plate can be attached to the inner and outer sides of the tube, and the ends of the heat-conducting plate are secured with clips, ensuring that the heat-conducting block 3 evenly wraps around the inner and outer walls of the tube. The heating coil 4 and the temperature probe 5 are inserted into the heat-conducting block. The controller is connected to the temperature probe 3 and the heating coil 4 via a control line. The controller 1 is powered on via a power line 7. When the controller 1 switch is turned on, the screen of the controller 1 first displays the real-time temperature of various parts of the tube, a function not found in existing heating and temperature control equipment. During use, the required preheating temperature of the tube is set on the controller 1. The controller 1 controls the heating coil 4 to automatically heat and evenly raise the temperature of various parts of the tube to the target preheating temperature, achieving a function that existing heating devices do not have. It features uniform heating of the tubes. After the tubes reach the preheated temperature, the controller automatically controls the heating and temperature control device to maintain a constant temperature, achieving a constant temperature function that is not available when using insulation materials. After the tubes are welded, the holding time, target cooling temperature, and cooling time can be set on controller 1 to achieve slow cooling control of the tubes.

[0022] The linking mechanism includes a hinge-type flexible hinge 8. As a further improvement of the present invention, the flexible hinge 8, compared with existing heating devices, can be matched with most tubular tubes, can be installed inside or outside the tube, and can achieve contact between the heat-conducting block and the tube.

[0023] The temperature measuring device includes a temperature probe 5 integrated in the heat-conducting block, a control line 6 for transmitting data, and a controller 1 for displaying the temperature. As a further improvement of the present invention, the temperature measuring device can measure the temperature during welding in real time through the temperature probe 5 integrated on the heat-conducting block, which helps the welder control the layer / pass temperature and obtain welding quality that meets nuclear-grade requirements.

[0024] This invention proposes a reliable temperature control device for welding insulation / temperature control of high-performance piping systems in ships, and for manual welding of critical welds. The device is a flexible chain-type device with a non-slip track, lightweight, and suitable for single-person hand-held movement. It is applicable to the entire welding process, including preheating / insulation, welding temperature control, and post-weld slow cooling. It can be flexibly positioned during the welding process, is practical, economical, convenient, and has strong processability.

Claims

1. A flexible chain-type heat preservation device for welding nuclear-grade pipe sections, characterized in that, There are multiple long strip-shaped heat-conducting blocks, which are placed horizontally and arranged in a row from top to bottom. The ends of two adjacent long strip-shaped heat-conducting blocks are connected in sequence by flexible hinges to form a complete heat-conducting plate. A locking buckle is fixed on the flexible hinge at the free end of the heat-conducting plate. After the two free ends of the heat-conducting plate are joined together, they are locked by the locking buckle. The heat-conducting plate contains a heating coil and a temperature probe. The controller controls the heating coil, and the temperature probe transmits signals to the controller.

2. The flexible chain insulation device for welding nuclear-grade pipe sections according to claim 1, characterized in that, The heating coil is located inside the heat-conducting block and is arranged in an S-shaped path from one end of the heat-conducting block to the other.

3. The flexible chain insulation device for welding nuclear-grade pipe sections according to claim 1, characterized in that, The heat-conducting plate is adsorbed onto the inner or outer surface of the nuclear tube, and after circling the nuclear tube once, it is locked in place by a locking buckle to form a cylindrical shape.

4. The flexible chain insulation device for welding nuclear-grade pipe sections according to claim 1, characterized in that, The controller is connected to a power source.

5. A flexible chain insulation device for welding nuclear-grade pipe sections according to claim 1, characterized in that, Two heat-conducting plates are located on both sides of the weld seam of the nuclear-grade pipe section.

6. The flexible chain insulation device for welding nuclear-grade pipe sections according to claim 1, characterized in that, The temperature probe transmits signals to the controller via a control line.

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