Dust-free construction management measures in the construction process of coating line
Dust-free construction, as an important management goal of coating line construction project management, points out the direction for us to formulate various rules and regulations and management measures in the process of coating line project management.
The proposal of dust-free construction is not only a breakthrough in project management concept, but also a major change in project management behavior mode.
Prerequisites for dust-free construction
To realize dust-free construction, it is necessary to determine a perfect technological scheme, select excellent construction teams, put forward industry benchmarking goals, arrange construction organization plans, formulate and publish reasonable rules and regulations, strictly manage daily, timely reward and punishment, and remedy measures under special circumstances.
Before dust-free construction management, the following preconditions must be met:
In terms of equipment, modular production and bolt connection of non-standard equipment are the core:
In order to ensure the cleanliness of the installation site, it is first necessary to require modular production of non-standard equipment. In the process of drawing countersignature and technical exchange between design institute and equipment manufacturer, it is emphasized that modular production should be fully considered at the beginning of equipment design. It is required to prohibit gas cutting, minimize the workload of welding, ensure the minimum workload of equipment production on the construction site, and greatly reduce the production of workshop waste and welding dust. Bolt connection is the main form of equipment installation on site, which reduces the welding workload on site.
In order to ensure the implementation of the above requirements, we determine the name of the equipment that must be manufactured in modules, and determine the structural form and content of each module in combination with the transportation conditions.
For non-standard buildings, mechanization and steel structures, it is required to organize the design by means of bolt installation, and the equipment can only enter the installation site after prefabrication.
Civil engineering should ensure two points:
Outside the factory building: complete the greening of roads outside and around the factory building.
Before the equipment enters the factory, the road greening outside the factory and around the factory has been basically completed. This measure ensures that dust is brought into the painting workshop as little as possible during the transportation of equipment, and dust around the factory is brought into the painting workshop as little as possible in windy weather.
Inside the factory; The following conditions are required:
(1) The workshop is basically sealed, and the doors of the workshop should be closed. Temporary measures should also be taken to close the reserved holes of logistics or installation equipment to prevent dust from entering the workshop.
(2) The equipment foundation and concrete floor of the workshop have been completed to reduce the dust in the workshop;
(3) Toilets, offices and auxiliary rooms can be put into use, thus reducing the domestic garbage generated by construction workers and ensuring a humanized construction environment;
(4) The first surface of the factory wall has been painted;
(5) Before the equipment enters the site, the closed workshop shall be thoroughly cleaned to remove the garbage left by civil works and the dust on the wall and ground.
Only under the above premise can dust-free construction be effectively implemented.
Three, dust-free construction management points:
If there is only a good premise, but there is no strict system and management measures, it is impossible to ensure the smooth realization of dust-free construction in the workshop. Strict system and management measures are the core of our dust-free construction. The main points of dust-free construction management are summarized as follows:
3. 1 factory building closing and deep cleaning before the equipment enters the site
Before the equipment enters the site, the workshop shall be inspected, mainly including the following work:
(1) Conduct a comprehensive inspection and check on the equipment foundation and reserved holes in the workshop to prevent the deviation between the foundation and reserved holes;
(2) Check the protective measures for the gate and reserved hole to ensure the gate and hole (including the hole on the roof, etc.). ) has been effectively closed. Temporary protective railings and cover plates shall be set for reserved holes between internal floors;
(3) Deep cleaning of plants;
Deep cleaning generally follows the principle of top-down cleaning. Combined with the essence of 5S site management, we divide the cleaning work into three times: the first time, the civil garbage was completely cleaned, with shovel as the main tool, and the cleaning focus was on the beam, wall, ground, trench and underground air duct of the factory building; The whole workshop was thoroughly cleaned for the second time, and the main tools were compressed air and brooms. , thoroughly clean the workshop; The third time is a thorough cleaning of the whole factory building. The main tools are rags and mops, and workshops (beams, floors, etc. ) It was thoroughly cleaned.
3.2 Pre-cleaning and protection shall be carried out during equipment prefabrication.
In order to prevent the hidden trouble that the equipment module can't be cleaned in the manufacturing process, it is necessary to countersign the equipment process manufacturing card of the equipment manufacturer according to the specific structure of the equipment, and carry out process control, mainly including: determining the area that can't be cleaned in the future, thoroughly cleaning it before assembly by tailor welding, and checking its cleanliness before assembly. For those that can be cleaned in the future, it is also necessary to fully wipe the module before shipment, and then use dust-proof film to protect it to prevent dust from appearing during transportation.
3.3 The equipment shall be thoroughly cleaned before installation.
When the equipment enters the workshop, it is necessary to observe the rules of closing the door at any time, and at the same time, before the equipment enters the workshop, try to remove the packaging outside the workshop. In order to ensure the cleanliness of the system, it is necessary to analyze the assembly structure of the system to determine which systems must be cleaned internally and the cleaning scheme before installation. Generally speaking, equipment cleaning before system installation can be divided into several levels (see Table 2):
Table 2: Classification of equipment cleaning grades and cleaning methods
Cleanliness grade
Specific parts
Cleaning method
comment
Level a
Piping system (pretreatment, electrophoresis system, paint conveying and mixing pipeline, public piping system, water supply and drainage system, etc.). )
Air duct system (all air ducts in the painting room, all air ducts in the polishing and cleaning room, all other air ducts and all hot air duct systems and triples in the drying oven)
Fire hose at the top of spray booth
Spray booth static and dynamic pressure chamber and spray booth wall plate
Before installation, the piping system should be purged with compressed air outside the workshop and then washed with water;
Wipe the inside of the air duct manually and check the cleanliness of the inner wall.
The inner surface of the fire-fighting pipeline is purged with compressed air, and the oil stain is wiped off by hand after the outer surface is purged.
Use manual cleaning before assembly.
assistant
Piping system (all exhaust pipes)
Non-standard room parts, cleaning between drying furnace modules, internal cleaning, etc.
Inner surface of air conditioning system
Wipe the inner surface by hand.
assistant
Tank system (pretreatment, electrophoresis tank, circulating tank, venturi part, etc.). )
Before entering the workshop, thoroughly clean it with a high-pressure water gun, and then enter the workshop for installation.
Made of stainless steel.
First-class cleaning: clean without sundries, particles, iron filings, oil stains and dust, and wipe with white gloves for cleanliness inspection.
Grade II: clean, free of sundries, particles, iron filings and obvious dust.
Through the above measures, the damage of impurities remaining in the pipeline to valves and pumps in the future can be reduced, and an important hidden danger of pump leakage can be eliminated, as well as the hidden danger that dust remains in the air duct in the production process and is continuously carried away by the wind, which affects the painting quality.
Timely cleaning and effective protection during equipment installation.
In the process of equipment installation, it should be analyzed according to the equipment installation process, which can be generally divided into two situations:
(1) Provide timely cleaning and maintenance between equipment installation processes, such as cable tray installation processes, such as bracket fixing, tray installation, cable laying and tray cover plate. After the cable laying is completed, the inner surface of the bridge must be wiped clean again before the cover plate can be installed.
Fig. 3 Cleaning the bridge site
(2) Pause in the process of equipment installation. For equipment and systems that cannot be installed at one time during installation, it is necessary to protect the equipment. The equipment involved in this kind of problem mainly includes: air duct, pipeline system (pretreatment, electrophoresis circulation pipeline, public power pipeline) and electrical bridge.
The protective measures in this process mainly adopt film packaging for protection.
3.5 Determine the finished product stacking area and protective measures.
For the equipment and materials that have been manufactured but cannot be installed in time, specify clear stacking areas and protection requirements. For air ducts and duct assemblies, the ports must be protected with film to prevent dust from entering. So as to ensure that the semi-finished products are well protected and the site is clean and tidy.
3.6 Delineate the on-site processing area and implement management.
Although modular production has been realized, there are still inevitable changes and small parts (such as on-site guardrails, pipelines and other parts that need to be assembled on site) in the construction site. For this kind of problem, the area will generally be demarcated and isolated with designated color plates to ensure that the installation site is clean and tidy. Local modification and a small amount of production work are allowed in the isolation area.
In order to ensure the cleanliness of the maintenance area, a management system is formulated, and the area is inspected regularly to ensure the cleanliness of the whole workshop. Fig. 4 Maintenance of machining area
3.7 Construction and cleaning shall be carried out simultaneously.
In the process of construction, in order to prevent dust accumulation on site, 6S management is required on site, and day-to-day cleaning is a very important part. For the work that produces more sundries and garbage, such as local transformation problems (cutting and welding), the construction personnel are generally required to ensure that the cleaning is carried out at the same time. For example, during welding construction, one person is required to clean up in time to ensure the cleanliness of the construction site.
Divide different cleaning areas and set up a professional cleaning team.
In order to ensure a good construction environment, it is necessary to establish the cleanliness standard, inspection system and detection method of the workshop during the installation process. Therefore, when installing equipment in the factory, the professional cleaning team also enters the workshop to clean it. Supervise and manage the cleaning operation through the cleanliness inspection of the workshop.
In the installation process, the cleanliness standard of the painting workshop can be formulated with reference to the classification management standard of the cleanliness of the painting line, which is generally divided into four grades for control. According to our experience, we have formulated management standards (see Table 3).
Table 3: Classification of Cleanliness Grades of Factory Buildings and Inspection Methods
grade
region
Cleanliness standard
Level a
Spray painting room, drying room, drying box, cleaning area, paint mixing room, cleaning room, etc.
The air particle size meter checks the number of dust particles in the air, and the white gloves check that there is no dust and oil pollution.
assistant
Pretreatment line, electrophoresis line, PVC line, etc.
White gloves are inspected for no obvious dust and no obvious oil stain.
Three levels
Grinding room, finishing line, wax spraying room, audit area, office, etc.
Visually, the site is clean and tidy, and the materials are placed at fixed points, without sundries and dust.
Totally good.
Logistics corridor, dressing room, personnel corridor, skid-mounted cleaning room, toilet, etc.
Materials shall be placed neatly, and there shall be no sundries and dust visually.
3.9 Formulate clear reward and punishment measures.
All management methods need someone to carry out. Only by establishing clear reward and punishment measures can the management system be carried out smoothly and effectively. Therefore, a series of rules and regulations and reward and punishment measures must be formulated before the equipment is installed in the site, and clearly publicized and publicized to all construction teams.
Fourth, the implementation effect of dust-free construction
Dust-free construction management in the construction project of coating line can improve the engineering quality, shorten the debugging period, improve the product quality and the first-time off-line qualification rate.
According to our practical application experience, through dust-free construction management, the cleaning work before production is shortened from the traditional two months to 15 days, and the cleaning cost is directly saved by about10.5 million yuan; The process debugging cycle has also been shortened from the traditional 3 months to about 1 month. During the trial production of the production line, the first off-line qualification rate of the coating has also been greatly improved, reaching more than 80% within 1 month, while it took 3 months for the previous coating line to reach more than 80%.