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Ultra-clean construction management of large area purification plant
2024/4/8
With the development of China's ultra-large scale integrated circuit industry, especially the development of the fifth generation TFT-LCD industry, and the continuous improvement of air purification in other industries, the construction of clean workshops is more and more, the purification level is constantly improving, the purification area is getting larger and larger, and the construction period requirements of the construction party are getting shorter and shorter. Reasonable construction organization is the guarantee of building a fast and qualified clean workshop. This paper takes a large clean production workshop as an example to introduce the clean assurance measures taken in the process of clean workshop installation.
The structural characteristics of large ultra-clean plant
The clean workshop adopts the form of new fan +FFU (fan filter unit) +FCU (fan coil), which is currently popular in the world, to ensure that the purified circulating air is realized by FFU, and the temperature and humidity in the room is guaranteed by the fresh air unit and FCU, and is divided into the following areas on the space facade.
1 Lower technical interlayer: the height is 5.3 meters, its main use is to set gas, water supply and drainage equipment, laying pipeline electrical lines, placing fresh air units and FCU. The floor is coated with epoxy artesian flat and enclosed by metal wall panels.
2 Production layer: The height of 5.4 meters, for the process room, equipment installation area, it is the core air of the whole plant in the vertical laminar flow state function. The raised floor is laid on the tic-tac-toe beam, and the surface of the tic-tac-toe beam is coated with water-based epoxy paint. The ceiling part is a grille ceiling system, with FFU in some areas and blind plates in the remaining areas, separated from the upper plenum layer. Metal wall panels around the working layer are closed and separated from the unclean area.
3 Plenum layer: The height is 2.5 meters, the fresh air and the mixed air entering the area through the return air tunnel are pressurized, and the FFU pressure filter is sent to the work area, and the automatic spray pipe system (for the working layer) and electrical system are set in the area. The upper compartment layer is separated from the unpurified part of the upper steel frame by a sandwich metal plate.
Three-dimensional cross-type construction organization design
According to the requirements of the control plan of the total construction period of the project, the total construction schedule of the installation project of the purification plant is formulated. When making the overall schedule, first consider meeting the requirements of the construction period, and then highlight the idea of "clean" as the goal of all work. According to the structural characteristics of the plant, the working layer is located in the middle of the plant and is the core area of the plant, which is the area to be ensured. To this end, we take the first outside and then inside, first do the raised floor, and then do the engineering type in the top plate and the lower technical sandwich of the static pressure box, and finally do the working layer of the core area.
2.1 Division of worksurfaces
In this project, the size of the hole on the shaft beam is 1.3mX1.3m, which is a great safety hazard. In view of this situation, the public hanger under the shaft beam is installed first, and then the safety net is laid after laying, and then the raised floor is installed. After the installation of the raised floor, it is divided into 5.3m above and below the working area. According to the requirements of the installation engineering construction schedule, the progress plan of the work in these two areas is formulated respectively.
2.2 Division of engineering control nodes
According to the characteristics of the project, seven engineering control nodes are set up, which are: clean room start, painting completion, movable floor completion, grid ceiling system completion, power transmission, process equipment moving in, completion.
2.2.1 Clean room starts
The construction conditions of the clean room are required to be closed construction, so the conditions for the start of the clean room are the completion of the construction of the building and the completion of the closure of the building.
2.2.2 Completion of painting
The tasks required to be completed by this control node include the completion of painting of waffle mesh panels, beams and walls in the production layer, the completion of painting of return air tunnel, the completion of installation of shared supports and safety nets, and the completion of drilling of movable floor support feet. The work content of large dust production such as drilling and other work content is arranged in this node.
2.2.3 The raised floor is complete
This node controls the installation of the raised floor, the middle coating of the lower technical interlayer, the installation of the top plate and wall panel of the plenum, the installation of air conditioners, pumps, and heat exchangers, the fabrication and installation of various air ducts, and the piping and electrical pipes of various pipelines.
2.2.4 The grid ceiling system is complete
The main control content of this node is the completion of the installation of the grid crane system, the installation of the wall panel of the lower technical layer, and the completion of the main pipe distribution of the air pipe and various pipelines, and the basic completion of the electrical distribution pipeline.
2.2.5 Powering off Nodes
This node controls that the air conditioner starts power supply test run for each unit. In addition, all air conditioning ducts are completed except for heat preservation, and all air conditioning piping is completed except for pressure test and heat preservation.
2.1.5 Process equipment moving in
This stage requires the completion of the internal installation of professional closure, the completion of air conditioning duct insulation, cooling water, pure water, drainage, vacuum, tap water and other pipeline system pressure test completed, power supply wiring completed, lighting power supply.
2.1.6 Completion
This node requires that the single test run is completed, and the debugging and testing of each system are qualified.
3.1 Personnel pollution control
The core of purification plant construction is "clean", and personnel are the biggest pollution source in the construction and installation process. Controlling the pollution of personnel is the primary problem to be solved in the construction organization design.
3.1.1 Certificate handling system
At each purification stage, the construction personnel entering the purification plant will be trained, and the corresponding name tags will be issued after passing, and only those wearing name tags will be allowed to enter the purification plant.
3.1.2 Personnel Direction
Clearly specify the route and direction of the flow of people, set up a personnel entrance and exit in the upper and lower working areas, and all personnel have only one flow route, taking this measure can effectively control the source of the flow of people.
3.1.3 Personnel purification
A special purification room is set up at the entrance of the flow of people for all the personnel to carry out personal purification, according to the requirements of different purification stages to change clothes, change shoes, wear hats, so that all the personnel in the clean area can carry out a personal and tool purification.
3.2 Logistics pollution control
Logistics is a big source of pollution second only to the flow of people, and all construction personnel and management personnel should be strictly in accordance with the purification requirements.
3.2.1 Special entrance for moving
In the upper and lower working areas each set up a special moving entrance, all materials can only enter through this moving entrance plant, take this measure to control the free entry of unclean materials.
3.2.2 Cleaning Materials
All the materials entering the purification plant should be cleaned and wiped with rags and water before moving in.
In the process of material purification, according to the function and role of the material in the production process, different purification standards are formulated in detail, and the phase-taking hydraulic measures are adopted. Materials for gas transmission, materials for pure water, fresh air transmission pipelines and valve groups, and materials for process equipment installation are listed as the focus of material purification to ensure the final use requirements of the purification plant.
3.3 Division of purification stage
The whole project of installation and construction is implemented in three stages according to the purification requirements, and the stage objectives and specific requirements are formulated.
3.3.1 General level pollution control stage
Before the start of this stage, in addition to the equipment moving into the reserved holes in the purification area, the Windows and interior painting of the building should be completed, and the reserved holes for air pipes and pipelines should be temporarily blocked. This stage can be defined as the completion of the wall panels around the upper and lower working faces, such as dust coating, air conditioning unit installation, power equipment, primary pipe distribution and wiring (cable bridge and electrical pipe distribution), movable floor installation, top wall panel installation, etc.
The goal of this stage is material purification, general cleaning and purification. At this stage, the materials are required to be cleaned after the work is finished, the vacuum cleaner is used to vacuum when the hole is opened, and the overall cleaning is carried out once a week. Before entering the second purification stage, it is necessary to carry out a thorough and comprehensive cleaning, and the dead corners and corners should be cleaned and cleaned.
3.3.2 Higher level pollution control stage
This stage can be defined as the operation process after the first stage and before the air blowing, such as the construction of the grid ceiling, electrical wiring and switchboard installation, and the construction of the lower sandwich machine pipeline and air duct equipment. At this stage, special sweeper is required to be set up to clean the entire working face, and each worker is required to clean the material, and the overall cleaning of the purification room is carried out once a week, and the dust production operation can not be carried out. To prepare for the installation of FFU and HEPA filters, arrange a comprehensive cleaning and scrubbing before entering the third purification stage, requiring pure water or alcohol as raw materials, fine cleaning with non-dust producing high-grade woven cloth, and turn on the vacuum suction system to vacuum each part.
3.3.3 High-level pollution control stage
This stage is defined as the construction process after air blowing until commissioning delivery, such as the installation of FFU and high efficiency filters, the floor coating (surface layer) of the lower layer, the test run of the equipment, the inspection of electrical equipment and the confirmation of various alarms, the testing of the purification room, etc.
At this stage, special sweepers are required to wipe with pure water or alcohol in the purification plant, and the dust-free chemical fiber material should be used in the cleaning cloth. All personnel entering the purification plant should wear purification clothing and purification shoes. Dust producing cartons are prohibited from entering the purification room, and ordinary paper and pencils are prohibited. Before the test, it is required to concentrate on a comprehensive wipe to ensure the quality of the test and create conditions for the installation of process equipment.
