Introduction to coating production line

Coating production line is also called coating assembly line, which refers to the process of coating on metal or non-metal surface to form a protective layer or decorative layer [coating, coating technology (method, equipment, environment), coating management are the three factors that affect the quality of coating]. It is suitable for surface painting, powder spraying, plastic spraying, etc. of workpieces. With the development of industrial technology, coating production line has developed from manual to industrial automation, and the degree of automation is getting higher and higher, which solves the problems of poor working environment, large workload, low efficiency, unstable coating quality and poor uniformity of manual coating operation. Therefore, the application of coating production line is becoming more and more extensive and has penetrated into many fields of national economy.

Composition of complete set of equipment of metal surface coating production line

● Main equipment: pre-treatment [degreasing, water washing, rust removal, water washing, surface conditioning, phosphating, drying], powder spraying room (paint spraying room); powder spraying (paint) gun, reciprocating machine; robot spraying; electrostatic spraying, sintering furnace, catenary (hanging rail) workpiece conveyor line, accumulation catenary conveyor line.
● The electrostatic powder spraying system is mainly composed of a set of powder supply devices (powder supply barrels, powder spraying rooms), one or more sets of electrostatic spray guns and control devices, an electrostatic generating device (usually configured in the electrostatic spray gun) and a set of powder recovery devices.
● Electrical control system, central automation, information, intelligent control system (composed of host computer (HMI), PLC, field instruments, etc. Among them, the automation system PLC mainly completes communication, data collection, important logic control, etc. The host computer plays a role in centralized monitoring and management).

Introduction to powder coating line

1. Powder spraying is to use powder spraying equipment (electrostatic spraying machine) to spray powder coating on the surface of the workpiece. Under the action of static electricity, the powder will be evenly adsorbed on the surface of the workpiece to form a powder coating; the powder coating is baked and leveled at high temperature to become a final coating with different effects (different types of powder coating effects); the spraying effect of powder spraying is better than the painting process in terms of mechanical strength, adhesion, corrosion resistance, aging resistance, etc., and the cost is also lower than the painting with the same effect.
2. Powder coatings are made of special resins, pigments, fillers, curing agents and other additives, mixed in a certain proportion, and then prepared by processes such as hot extrusion and crushing and screening. They are stable in storage at room temperature, and are heated, baked, melted and solidified by electrostatic spraying, friction spraying (thermosetting method) or fluidized bed dipping (thermoplastic method), so as to form a smooth and bright permanent coating film to achieve the purpose of decoration and corrosion protection.
3. The characteristics of powder coatings are:
● The product is non-toxic, does not contain solvents and does not contain volatile toxic substances, so there is no problem of poisoning, fire, and "three wastes" emissions, which fully meets the requirements of the national environmental protection law.
● The utilization rate of raw materials is high. The powder produced by some well-known brand powder suppliers can be recycled, and the highest utilization rate can even reach more than 99%.
● After the pre-treatment of the coated object, a one-time construction without primer is required to obtain a coating film of sufficient thickness, which is easy to realize automatic operation, with high production efficiency and cost reduction.
● The coating is dense, has good adhesion, impact strength and toughness, high corner coverage, and has excellent chemical corrosion resistance and electrical insulation properties.
● Powder coatings are safe and convenient to store and transport.
4. Compared with traditional paint processes, the advantages of powder coating are:
● High efficiency: Because it is a one-time film formation, it can increase productivity by 30-40%
● Energy saving: Reduce energy consumption by about 30%
● Less pollution: No organic solvent volatilization (does not contain harmful gases such as toluene and xylene in paint coatings).
● High coating utilization rate: It can reach more than 95%, and the powder can be used multiple times after recycling.
● Good coating performance: The one-time film thickness can reach 50-80μm, and its comprehensive indicators such as adhesion and corrosion resistance are better than paint processes.
● High yield rate: Before curing, it can be re-sprayed twice. There are many types of powder coating processes, the most common ones are electrostatic powder spraying and dipping.
● Powder coating is a new type of solvent-free 100% solid powder coating. It has the characteristics of no solvent, no pollution, saving energy and resources, reducing labor intensity and high mechanical strength of coating film.
5. In the coating production line, whether it is electrophoretic drying of pre-treatment, or primer, topcoat and sealant, powder coating need to be dried and cured, and the drying furnace is an indispensable equipment. The workpiece enters the drying furnace after being cleaned by the pre-treatment equipment. The drying furnace is used to dry the paint film and sealant, plastic powder, and powder coating after spraying or dipping, remove the residual moisture on the surface, and level and solidify the paint film and powder. Its temperature uniformity is an important indicator to ensure the quality of the coating. It is mainly used for baking paint and plastic powder leveling and curing equipment on the surface of metal or non-metal (plastic, wood) parts, so as to form a protective layer or decorative layer on the surface.
6. Advantages of drying furnace
● Sturdy and durable: The frame of the room is designed and made of steel structure, and the wall is sealed with composite insulation board. The room is stable and safe, with good insulation performance, large bearing capacity, long service life, beautiful appearance and fast construction;
● Good curing effect: The indoor thermal insulation is good, and the advanced hot air circulation system makes the workpiece heated evenly, and the best film quality can be obtained;
● High safety performance: The heat exchanger is made of high-quality stainless steel and scientifically designed and welded. It is equipped with a combustible gas concentration detection device. When a certain concentration is reached, it will immediately alarm and stop running. It is safe and reliable;
● High degree of automation: Automatic Control system, modular design, independent control console, intelligent temperature control instrument temperature control, automatic shutdown and other functions, simple operation;
● Environmental protection and energy saving: the effective temperature zone of the furnace is long, the coating does not fall off, effectively improves efficiency, saves energy, adopts a fully enclosed structure, the indoor is clean and environmentally friendly, and the exhaust gas purification rate is high;
● The paint color is brighter: the air flow speed in the furnace is small, and the powder coating is not easy to blow off in the furnace, ensuring the uniformity of the film thickness, and different colors can be dried and cured at the same time;
● Non-standard customization: the drying furnace is customized according to customer requirements to ensure the applicability, stability, practicality and energy saving of the equipment.

Production line equipment selection suggestions

1、According to the investment and production capacity and process requirements, the conveying system is selected: catenary workpiece conveyor line, suspended rail workpiece conveyor line, and accumulation catenary conveyor line. The spraying method can be selected from manual spraying, reciprocating spraying, and robot spraying.
2、Spraying equipment can be selected from electrostatic spraying, friction spraying (thermosetting method), and fluidized bed dipping (thermoplastic method).  Heating and drying furnace selection:
● Classification by form: U-type bridge drying furnace, π-type drying furnace, straight-through drying furnace;
● Classification by heat source: electric heating drying furnace, natural gas heating drying furnace, liquefied petroleum gas hot drying furnace;
● Classification by heating method: hot air circulation heating drying furnace, radiation heating drying furnace.

Introduce

As a technology innovation enterprise, our company integrates independent research and development, production, sales, and after-sales. It has a strong R&D team, business spread all over the country and abroad, and rich technical experience. It can solve various coating, surface treatment and other problems for customers. In this way, it can create an efficient and environmentally friendly coating production line and meet customer customization needs. As a coating surface treatment engineering system integrator, it can undertake EPC general contracting projects. According to the contract agreement, it undertakes the design, procurement and construction, trial operation services and other work of the engineering project, and is fully responsible for the quality, safety, construction period and cost of the contracted project. Finally, it submits an engineering project that meets the functional requirements to the owner and completes the turnkey project. Automobile factory EPC general contracting: planning and designing the plot according to the technological characteristics of the automobile industry, and carrying out equipment procurement, installation, after-sales service, etc. according to the contract agreement. 24-hour active response and efficient service, so that customers can rest assured and worry-free.

Application of powder coating production line

Powder coating production line is widely used in highway guardrails, railway guardrails, isolation fences, airports, gardens and outdoor facilities for corrosion protection; aluminum profiles, curtain walls, radiators, anti-theft doors, chassis, cabinets, metal furniture, indoor shelves, baskets, supermarket shelves, fitness equipment; machinery manufacturing industry: automobiles, motorcycles, tractor parts, aerospace, ships, military industry, wind power industry, daily hardware, household appliances, 3C electronics, agricultural machinery, engineering machinery; rail transit, construction, bridges, structural parts, sheet metal parts; surface treatment of pipes, valves, etc., epoxy resin coated steel bars, steel pipe production lines. Railways, highways, bridges, airports, seaports, docks, offshore buildings, high-rise building basements, underground buildings, garages, tunnels, dams and sewage treatment pools, chemical buildings, chemical industry parts that require heavy corrosion protection and other projects in harsh environments.