Nuclear power carbon steel small pipe prefabrication process and assembly line

Abstract

The invention belongs to a prefabrication process, and particularly relates to a nuclear power carbon steel small pipe prefabrication process and an assembly line. The invention discloses a nuclear power carbon steel small pipe prefabrication process. The nuclear power carbon steel small pipe prefabrication process comprises the following steps of S1, material receiving, S2, material codes, needing to trace items, of prefabricated materials, S3, elbow prefabrication, S4, pipe fitting polishing, S5, assembly welding, S6, pipeline marking, S7, detection, S8, surface treatment and S9, pipe section warehousing and ex-warehousing. The method has the remarkable effects that 1) the work type subdivision of the workshop is defined, so that the personnel structure is reasonably matched; secondly, the layout of a workshop is improved, the process spacing is adjusted, and secondary carrying can be avoided by arranging a flat car; 3) a traffic light system is arranged, so that the quality development progress can be clearly understood; (4) 30 persons are needed in a small workshop before improvement, only 23 persons are needed after improvement, the number of the persons is reduced by 7, and the number of the persons is reduced by 23.33%; the workshop efficiency is not 17.44 inches per person per day before improvement, the workshop efficiency is not 41.44 inches per person per filling after improvement, and the efficiency is obviously improved by 137.61%.

Description

Technical Field

[0001] The invention belongs to a prefabrication process, and in particular relates to a prefabrication process and an assembly line for a nuclear power carbon steel small tube. Background Art

[0002] The total prefabrication and installation volume of the auxiliary pipelines for the Hualong One reactor type of nuclear power plants is about 260,000 meters, of which the prefabrication and installation volume of small pipes accounts for about 62% of the prefabrication and installation of EM4 auxiliary pipelines. The quality and progress of the prefabrication of small pipes have a crucial impact on the installation and commissioning process during the construction phase of nuclear power plants.

[0003] In the past, when setting up small pipe prefabrication workshops in production areas, the design institute would directly delineate the scope of the factory space, and then arrange it directly according to the size of the equipment and tools, without considering factors such as the actual material placement, work schedule, and process sequence. In addition, the arrangement of personnel and work processes was unreasonable, the flow of personnel was large, transport carts could not be used routinely, and the processes of each project were independent, resulting in large personnel investment in the small pipe workshop and low production efficiency.

[0004] Before the small pipe prefabrication workshop was planned for production lines, there were many defects and problems, which led to a lot of unnecessary waste and inefficiency in the production process. The specific manifestations are as follows:

[0005] 1. Low production capacity: Due to the large number of unnecessary steps in the production process, the overall efficiency of the production line is low, which cannot better meet market demand and causes waste of resources.

[0006] 2. High manufacturing costs: The process is not smooth, resulting in frequent interruptions and stagnation in the production process, which wastes workers' production time and increases production costs.

[0007] 3. Quality is difficult to guarantee: Due to excessive manual operations and multiple handling in the production process, product defects are likely to occur, affecting product quality and customer satisfaction.

[0008] 4. Opaque process: The production process without assembly line planning is difficult to make transparent, making it difficult to find problem points in the production process and thus unable to optimize the production process.

[0009] 5. Long production cycle: Due to the unsmooth process, there are many waiting and interruptions, resulting in a long production cycle and unable to meet the market demand for fast delivery. Summary of the invention

[0010] Aiming at the defects of the prior art, the present invention provides a nuclear power carbon steel small tube prefabrication process and production line.

[0011] The present invention is implemented as follows: a nuclear power carbon steel small pipe prefabrication process, comprising the following steps: S1, material collection, S2, prefabricated material traceability item material coding, S3, bent pipe prefabrication, S4, pipe grinding, S5, assembly welding, S6, pipeline marking, S7, detection, S8, surface treatment, S9, pipe section storage and warehousing.

[0012] As described above, a prefabrication process for small carbon steel tubes for nuclear power generation is described, wherein S1, material collection, automatically generates item information through the item information management system, and the material personnel collect the materials according to the material delivery order. At the same time, the temporary storage shelves for pipelines are improved, and eye-catching red and white safety warning tapes are posted on the shelves. It is closely connected with the next S2 cutting and unloading process to reduce the transportation time of the pipe sections and ensure that the small tubes do not fall to the ground.

[0013] As described above, a prefabrication process for small carbon steel tubes for nuclear power plants, wherein, S2, the prefabricated materials need to trace the item material codes to ensure accurate material cutting and reduce material cutting waste. After the workshop receives the materials, they are first classified according to the material coding isometric diagram of the same pipe diameter, and the cutting lengths are arranged from long to short. After the actual usage is compared with the requisition data, the part numbers are annotated on the drawings with a pencil, thereby ensuring that the pipe section materials are sufficient and not mixed.

[0014] The unloaded pipes can be directly sent to the next process, or a flatbed cart can be added for transportation. Instead of a large number of manual operations, one person can now push multiple pipes using a flatbed cart, making transportation within the workshop convenient and fast.

[0015] The unloading area is equipped with a pipe cutter and a metal band saw. The cutting personnel first use the metal band saw to automatically cut the material, and then operate the pipe cutter to cut another pipe. In this way, one person can operate multiple machines and improve production efficiency.

[0016] As described above, a prefabrication process for small carbon steel tubes for nuclear power generation, wherein S3, prefabrication of bent tubes, uses a tube bender to bend the tubes according to the bending radius marked on the drawing, and in addition, the tube branch device in the prefabricated tube bending link is improved: the tube branch device is heavy and difficult to carry, and the height adjustment requires rotating bolts. After the tube branch device is improved, the supporting feet are equipped with movable and positionable universal wheels, and scale positioning is performed according to the required elevation of different tube diameters to improve the efficiency of tube bending.

[0017] As described above, a prefabrication process for small carbon steel tubes for nuclear power generation, wherein, in S4, the tube is polished, and a beveling machine is used for beveling. Meanwhile, a matching processing platform is set according to the beveling machine.

[0018] S5, group welding, the welding joint adopts the spot welding separation mode, so that the workshop grouping points are concentrated, the prefabrication workshop grouping adopts the matching pipe clamps and grouping tooling, and the workshop is equipped with a high-altitude rotating welding handle line to avoid fatigue of the welder's welding arm;

[0019] S6, pipeline marking, after the welds are completed, each spot weld must have a clear weld identification mark. The marking area uses a curved surface marking integrated system. The mark is the official pipe section number, and quality inspection is carried out at the same time.

[0020] As described above, a nuclear power carbon steel small pipe prefabrication process, wherein S7, detection, first set up a traffic light system in the prefabrication workshop, representing the quality elimination point indication system, the workshop spot welding area, welding area, visual inspection area all need the cooperation of quality inspection engineers to eliminate points, as long as the traffic light is set, the quality inspection engineer can judge whether there is a need for elimination points according to the color of the traffic light, and the quality inspection engineer can also give feedback to the construction personnel whether the elimination points are passed according to the color of the light,

[0021] At the same time, quality inspection engineers conduct random sampling and commission non-destructive testing based on the welding input data in the item information management system according to the liquid penetration and flaw detection ratio.

[0022] As described above, a nuclear power carbon steel small pipe prefabrication process, in which S8, surface treatment, adopts sandblasting and paint treatment, the pipeline is treated by pickling and passivation, using a special pickling and passivation machine and pickling and passivation paste for treatment, and can be used directly without wearing protective equipment, which is fast, efficient and environmentally friendly.

[0023] As described above, a nuclear power carbon steel small pipe prefabrication process, wherein S9, pipe section storage and warehousing, after completing the above process, the information can be entered into the system to carry out the storage and warehousing of the pipe sections. By inputting drawings, materials, quality plans, welding, non-destructive testing, storage and warehousing and other data into the information management system, a complete information management platform is formed, in which the current production task completion status can be timely queried, analyzed, planned and counted.

[0024] A nuclear power carbon steel small pipe prefabrication production line, wherein the production line includes a material storage area with sequentially connected processes, a production line area, a cutting area, a pipe bending area, a spot welding area, an assembly welding area, a marking area, a semi-finished product storage area, and a pickling and passivation area.

[0025] As described above, a nuclear power carbon steel small tube prefabrication production line, wherein the production line area includes three production lines, namely A1, A2, and B, wherein the B production line corresponds to the case of a straight tube without an opening; the A1 production line corresponds to the case of a straight tube with an opening; and the A2 production line corresponds to the case of a curved tube with an opening.

[0026] The significant effect of the present invention is that the present invention can be improved or transformed according to the description of the present invention by ordinary technicians in the field, and all these improvements and transformations belong to the protection scope of the claims attached to the present invention.

[0027] The present invention is suitable for large and medium-sized pipeline prefabrication and installation projects with high quality requirements, such as nuclear power, military industry, chemical industry, and electric power, which require the establishment of prefabricated plants, and prefabrication of small pipes with a pipe diameter less than or equal to DN50.

[0028] The present invention optimizes the processes of material collection, material cutting, pipe bending, groove grinding, assembly, welding and the connection paths between the processes, and divides the original construction line into three lines, so as to maximize the workshop production and minimize the waste.

[0029] After the present invention resets the working procedures, it can clarify the subdivision of the types of work in the workshop, reorganize the job configuration of the workshop, separate high-skilled and low-skilled jobs, and make the personnel structure reasonably matched. At the same time, each operation point implements a flow division mode, implements distribution according to work, and improves the enthusiasm of the personnel.

[0030] Specifically, the present application has the following advantages:

[0031] 1) After the present invention re-arranges the process, the types of work in the workshop can be clearly subdivided, the job configuration of the workshop can be re-arranged, and high-skilled and low-skilled jobs can be divided to make the personnel structure reasonably matched. At the same time, each operation point implements a flow division mode, implements distribution according to work, and improves the enthusiasm of personnel;

[0032] 2) Improve the layout of the workshop, adjust the process spacing, and set up flatbed trucks to eliminate secondary transportation. At the same time, the information management system can timely query, analyze, plan, and count the completion status of current production tasks;

[0033] 3) Setting up a traffic light system can help you understand the quality progress at a glance. Quality inspection engineers can also give feedback to construction workers based on the color of the light to determine whether they have passed the inspection, thereby improving project management.

[0034] 4) Before the improvement, the small pipe workshop required 30 people, but after the improvement, only 23 people were needed, a reduction of 7 people, a reduction of 23.33%; before the improvement, the workshop efficiency was 17.44 inches / person / day, but after the improvement, it was 41.44 inches / person / day, an efficiency increase of 137.61%, a significant improvement. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Carbon steel prefabrication production line process flow

[0036] Figure 2 Workshop assembly line layout

[0037] In the figure: L1. Material storage area, A1. A1 assembly line transverse flow area, A2. A2 assembly line transverse flow area, BB assembly line transverse flow area, L2. Pipe cutting machine, L31. Grinding area 1, L32. Grinding area 2, L33. Pipe bending area, L4. Spot welding area, L5. Assembly welding area, L51. Marking area, L6. Semi-finished product storage area, L7. Pickling and passivation area DETAILED DESCRIPTION

[0038] A nuclear power carbon steel small tube prefabrication process comprises the following steps:

[0039] S1, material collection, automatically generates item information through the item information management system, and material personnel collect materials according to the material delivery order. At the same time, the temporary storage shelves for pipelines are improved, and eye-catching red and white safety warning tapes are posted on the shelves. It is closely connected with the next S2 cutting and unloading process to reduce the time of pipe section transportation, basically ensuring that small pipes do not fall to the ground.

[0040] S2. Prefabricated materials need to trace item material codes to ensure accurate cutting and reduce material waste. After receiving the materials, the workshop first classifies them according to the material coding isometric drawings of the same pipe diameter, and arranges the cutting lengths from long to short. After comparing the actual usage with the receipt data, use a pencil to note the part number on the drawing to ensure that the pipe section material is sufficient and not mixed. This construction mode is completely different from the random cutting of small pipes in existing nuclear power plants according to each isometric drawing.

[0041] The cut pipes can go directly to the next process, or a flatbed cart can be added for transportation. Instead of a large number of manual operations, one person can now push multiple pipes using a flatbed cart, making transportation within the workshop convenient and fast.

[0042] The unloading area is equipped with a pipe cutter and a metal band saw. The metal band saw can eliminate the need for manual operation during material cutting. The cutting personnel first use the metal band saw to automatically cut the material, and then operate the pipe cutter to cut another pipe. In this way, one person can operate multiple machines, improving production efficiency.

[0043] S3, prefabrication of pipe bending, using a pipe bending machine to bend pipes according to the bending radius marked on the drawing, and improving the pipe branch in the prefabricated pipe bending process: the pipe branch is heavy and difficult to carry, and the height adjustment requires rotating bolts. After the pipe branch is improved, the supporting feet are equipped with movable and positionable universal wheels, and the scale positioning is performed according to the required elevation of different pipe diameters to improve the efficiency of pipe bending;

[0044] S4, pipe grinding. Since the grinding points of pipes are relatively concentrated and a large number of pipes are used every day, a grinding platform is set up in the workshop with a bench vise on it. The grinders are equipped with seats and can grind while sitting.

[0045] Use a clamp-type beveling machine for beveling processing. At the same time, set up a matching processing platform according to the beveling machine, which reduces the labor intensity of employees and improves the efficiency of pipe beveling processing.

[0046] S5, group welding, the welding joint adopts the spot welding separation mode, so that the workshop grouping points are concentrated, and the prefabrication workshop grouping adopts the matching pipe clamps and grouping tooling, which can reduce the input of group pipe workers and spot welders. At the same time, a high-altitude rotating welding handle line is set up in the workshop to avoid fatigue of the welder's welding arm;

[0047] S6, Pipeline marking, after the welds are completed, each spot weld must have a clear weld identification mark. The marking area uses a curved surface marking integrated system. The mark is the official pipe section number, which is convenient for welders to fill in the welding material receipt certificate and conduct quality inspection at the same time;

[0048] S7, inspection, first set up a traffic light system in the prefabrication workshop, which represents the quality elimination point indication system. The spot welding area, welding area, and visual inspection area of ​​the workshop all require the cooperation of quality inspection engineers to eliminate points (confirm that the process is completed). As long as the traffic lights are set, the quality inspection engineers can judge whether there is a need for elimination points based on the color of the traffic lights. The quality inspection engineers can also give feedback to the construction personnel based on the color of the lights whether the elimination points have been passed.

[0049] At the same time, the quality inspection engineer conducts random sampling and commissioned non-destructive testing based on the welding data entered in the item information management system according to the liquid penetration and flaw detection ratio;

[0050] S8, surface treatment, using sandblasting and paint treatment, the pipeline is treated by pickling and passivation, using a special pickling and passivation machine and pickling and passivation paste for treatment, it can be used directly without wearing protective equipment, fast, efficient and environmentally friendly;

[0051] S9, pipe section in and out of warehouse, after completing the above process, you can enter the information into the system to carry out the pipe section in and out of warehouse. By entering the drawings, materials, quality plans, welding, non-destructive testing, in and out of warehouse and other data into the information management system, a complete information management platform is formed. In the information management system, you can timely query, analyze, plan, and count the completion status of the current production task.

[0052] A nuclear power carbon steel small pipe prefabrication line, the original workshop one line, modified to increase the A1, A2, B three lines, the prefabricated pipe according to the straight pipe cutting and bending pipe cutting for separation, such as Figure 2 :

[0053] If the drawing design is a straight pipe without an opening, it will be implemented according to the B assembly line;

[0054] If the drawing design is a straight pipe with an opening, it shall be implemented according to the A1 assembly line;

[0055] When the drawing design shows that the elbow has an opening, it is implemented according to the A2 production line.

[0056] The workshop assembly line layout, electric welding area, assembly welding area and other areas are U-shaped, with the characteristics of U-shaped assembly line + straight line, which connects the processes compactly and uses mobile carts to eliminate secondary handling. This can reduce the circulation time of pipelines during the prefabrication process, reduce process waste and improve work efficiency.

Claims

1. A process for prefabrication of nuclear power carbon steel small tubes, characterized in that: The process includes the following steps: S1, material collection, S2, material coding of items that require traceability of prefabricated materials, S3, prefabrication of bent pipes, S4, grinding of pipe fittings, S5, assembly and welding, S6, pipe marking, S7, testing, S8, surface treatment, S9, storage and warehousing of pipe sections.

2. A nuclear power carbon steel small tube prefabrication process as claimed in claim 1, characterized in that: S1, material collection, automatically generates item information through the item information management system, and material personnel collect materials according to the material delivery order. At the same time, the temporary storage shelves for pipelines are improved, and eye-catching red and white safety warning tapes are posted on the shelves. It is closely connected with the next S2 cutting and unloading process to reduce the transportation time of pipe sections and ensure that small pipes do not fall to the ground.

3. A nuclear power carbon steel small tube prefabrication process as claimed in claim 2, characterized in that: S2, prefabricated materials need to trace the item material code to ensure accurate material cutting and reduce material waste. After the workshop receives the materials, it first classifies them according to the material coding isometric diagram of the same pipe diameter, and arranges the cutting length from long to short. After comparing the actual usage with the receipt data, use a pencil to annotate the part number on the drawing to ensure that the pipe section material is sufficient and not mixed. The unloaded pipes can be directly sent to the next process, or a flatbed cart can be added for transportation. Instead of a large number of manual operations, one person can now push multiple pipes using a flatbed cart, making transportation within the workshop convenient and fast. The unloading area is equipped with a pipe cutter and a metal band saw. The cutting personnel first use the metal band saw to automatically cut the material, and then operate the pipe cutter to cut another pipe. In this way, one person can operate multiple machines and improve production efficiency.

4. A nuclear power carbon steel small tube prefabrication process as claimed in claim 3, characterized in that: S3, prefabrication of bent pipes, using a pipe bender to bend pipes according to the bending radius marked on the drawing. In addition, the pipe branch device in the prefabricated pipe bending process is improved: the pipe branch device is heavy and difficult to carry, and the height adjustment requires rotating bolts. After the improvement of the pipe branch device, the supporting feet are equipped with movable and positionable universal wheels, and scale positioning is performed according to the required elevation of different pipe diameters to improve the efficiency of pipe bending.

5. A nuclear power carbon steel small tube prefabrication process as claimed in claim 4, characterized in that: S4, grinding of pipe fittings, using a clamp-type beveling machine for beveling processing, and setting up a matching processing platform according to the beveling machine. S5, group welding, the welding joint adopts the spot welding separation mode, so that the workshop grouping points are concentrated, the prefabrication workshop grouping adopts the matching pipe clamps and grouping tooling, and the workshop is equipped with a high-altitude rotating welding handle line to avoid fatigue of the welder's welding arm; S6, pipeline marking, after the welds are completed, each spot weld must have a clear weld identification mark. The marking area uses a curved surface marking integrated system. The mark is the official pipe section number, and quality inspection is carried out at the same time.

6. A nuclear power carbon steel small tube prefabrication process as claimed in claim 5, characterized in that: S7, inspection, first set up a traffic light system in the prefabrication workshop, which represents the quality elimination point indication system. The spot welding area, welding area, and visual inspection area of ​​the workshop all require the cooperation of quality inspection engineers to eliminate points. As long as the traffic lights are set, the quality inspection engineers can judge whether there is a need for elimination points based on the color of the traffic lights. The quality inspection engineers can also give feedback to the construction personnel based on the color of the lights whether the elimination points have been passed. At the same time, quality inspection engineers conduct random sampling and commission non-destructive testing based on the welding input data in the item information management system according to the liquid penetration and flaw detection ratio.

7. A nuclear power carbon steel small tube prefabrication process as claimed in claim 6, characterized in that: S8, surface treatment, using sandblasting and painting treatment method, the pipeline is treated by pickling and passivation, using a special pickling and passivation machine and pickling and passivation paste for treatment, without wearing protective equipment can be used directly, fast, efficient and environmentally friendly.

8. A nuclear power carbon steel small tube prefabrication process as claimed in claim 7, characterized in that: S9, pipe section in and out of warehouse. After completing the above process, you can enter the information into the system to carry out the pipe section in and out of warehouse. By inputting drawings, materials, quality plans, welding, non-destructive testing, in and out of warehouse and other data into the information management system, a complete information management platform is formed. In the information management system, you can timely query, analyze, plan and count the completion status of the current production tasks.

9. A nuclear power carbon steel small pipe prefabrication line, characterized by: The assembly line includes a material storage area where the processes are sequentially connected, an assembly line area, a cutting area, a pipe bending area, a spot welding area, an assembly welding area, a marking area, a semi-finished product storage area, and a pickling and passivation area.

10. A nuclear power carbon steel small pipe prefabrication line as claimed in claim 9, characterized in that: The assembly line area includes three assembly lines, namely A1, A2, and B. Among them, assembly line B corresponds to the situation of a straight pipe with no opening; assembly line A1 corresponds to the situation of a straight pipe with an opening; and assembly line A2 corresponds to the situation of a curved pipe with an opening.

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