Vertical Sinking Design for Bubble-Free Coating in High-Temperature Automatic Immersion Coating Line

Equipment Description:

I. Dipping Principle
‌1. Fluidized Bed Powder Suspension Technology‌
Compressed air passes through a porous air-permeable plate to form a fluidized suspension layer of PVC/PE powder (the fluidization factor needs to be determined experimentally; the suspension ratio is typically controlled at 30-50%). When the workpiece is immersed, the powder adheres evenly to the surface.

The high-temperature dipping line utilizes a vertical sinking immersion design, utilizing gravity and airflow to reduce coating bubbles and is suitable for large-area mesh (such as insulation barriers and welded wire mesh).
‌2. High-Temperature Plasticization and Curing‌
After dipping, the workpiece is heated to the powder melting temperature (230-250°C for PVC and 400°C for PE). This temperature is controlled in a double-layer oven with segmented, circulating hot air to ensure temperature uniformity (temperature difference ≤ ±5°C) and prevent bubbling or unmelted coating.

The plasticization stage requires precise time control (10-60 seconds) to adjust the coating thickness to 0.4-1.0mm.

II. Process Flow and Key Parameters
1. Mesh Loading → Surface Cleaning → High-Frequency Preheating → Fluidized Bed Dipping → High-Temperature Plasticizing → Cooling and Shaping → Quality Inspection → Automatic Unloading
2. Key Process Parameters:
Dipping Time: 10-60 seconds (control thickness 0.4-1.0mm);
Plasticizing Temperature: PVC 230-250°C, PE 400°C

III. Technical Parameters and Application Scenarios

Typical Applications:
Highway fencing, welded mesh anti-corrosion coating (load capacity 200-300kg/frame);
Livestock protection netting, Dutch mesh surface coating.

V. Equipment Advantages
Efficient Temperature Control: Optimized preheating and plasticizing processes reduce energy consumption by 15-20%;
Modular Design: Supports expansion of functional modules such as exhaust gas purification and automatic detection.

Main structures and components:

I. Core Processing Units
1. Dipping Machine
Fluidized Bed System: A porous bottom plate interacts with compressed air to create a fluidized suspension layer of PVC/PE powder (30-50% suspension ratio). The workpiece descends vertically into the suspension layer, achieving uniform coating coverage.
High-Temperature Heating Module: A gas-fired or electric heating system provides a temperature control range of 150-400°C to accommodate the melting requirements of different materials (e.g., PVC requires 230-250°C, PE requires 400°C), with a temperature control accuracy of ±5°C.
2. Pretreatment Module
Surface Pretreatment Equipment: This includes degreasing, pickling, and phosphating tanks, removing oil and oxides from the workpiece surface and forming an active layer to enhance coating adhesion.
Preheating Unit: A high-frequency induction heating device preheats the workpiece to 80-120°C, shortening subsequent dipping time and optimizing process efficiency.

II. Conveying and Automation System
‌1. Conveyor Chain/Mesh Belt
‌Variable Frequency Drive System, with a linear speed of 0.5-2 m/min, adapts to the continuous conveying of workpieces of varying sizes.
‌Customized hangers (single-rack load capacity 200-300 kg) are compatible with vertical suspension requirements such as welded mesh and isolation fences.
‌2. Robotic Arm Assembly
‌Automatic loading and unloading robotic arms linked to a PLC control system, with a daily processing capacity of 80,000-100,000 pieces, reducing manual intervention.
‌Pneumatic clamps ensure no deformation of workpieces during conveying.

‌III. Post-Processing and Temperature Control Unit
‌1. Plasticizing and Curing Oven
‌Double-layer oven structure (customizable length 15-20 m). The bottom layer is gas-fired or electric-heated, while the upper layer circulates hot air to ensure temperature uniformity and prevent blistering or unmelted coatings.
‌The temperature control range covers 230-400°C, with step-by-step adjustment to accommodate materials such as PVC and PE. 2. Cooling and Forming Module

A water-cooled spray or air-cooling system rapidly reduces temperatures, preventing coating deformation and improving forming efficiency by 20-30%.

An optional conductivity detector provides real-time monitoring and alarms for coating defects such as pinholes and bubbles.

IV. Auxiliary and Environmental Systems
1. PLC Control Center

Integrated temperature and speed sensors coordinate adjustment of parameters such as dipping time and plasticizing temperature, supporting fault alarms and emergency shutdown protection.
2. Environmental Components

Centrifugal filtration waste powder recovery system achieves a powder utilization rate of ≥90%.

Catalytic combustion equipment treats exhaust gas, achieving a VOC purification rate of ≥90%.

Features:

1.High cost performance: Based on the customer's product positioning and development strategy, and with economic affordability as the foundation, we achieve the best cost performance.
2.The advanced and meticulous design concept of the equipment, along with the highly automated industrial equipment, showcases the image of a modern and advanced enterprise.
3. It has high adaptability, meeting the current production requirements and reserving room for development, taking into account the needs of increased production and improved quality in the future.
4.Quality compliance strictly adheres to the ISO900 quality management system, with every minute detail of the entire equipment installation being strictly controlled.

Domestic large-scale coating equipment, intelligent equipment, and environmental protection equipment production enterprises-Zhejiang Huier Coating Environmental Protection Equipment Co., Ltd has 37 years of experience industry team in the powder coating equipment,intelligent equipment and environmental protection equipment.It is the national high and new tech enterprise,Specialized, refined, and innovative small and medium-sized enterprises， scientific and technological SMES 27years specialized R&D, design, manufacture, installation, commissioning ,maintenance of varies coating equipment, automatic equipment, intelligent control system, waste water,waste gas environmental protection equipment and treatment engineering.The company is located in Wukang Street, Deqing County, covers an area of 30,000 square meters, workshop of more than 20,000 square meters, more than 200 employees. The company has passed ISO9001 international system certification, ISO14001 environmental management system certification and ISO45001:2018 Occupational health and safety management system certification, and obtained more than 40 national patents.

The company actively and constantly introduce excellent talents, focus on the development of coating equipment and environmental protection equipment of new technology, new process and new products every year.It is the mission of all staff to continuously develop and grow, meet the needs of customers and create value for customers.

The products are used in all kinds of metal surface, plastic, aerospace, auto parts, mechanical equipment, furniture and other surface treatment.It will meet the customer needs, because it adopts automatic production to anti-corrosion and powder coating the user's products,coating solid bright.

In aerospace, household appliances, light industry, furniture, machine tools, construction, motorcycles, automobiles, communications, aluminum, electric power, agricultural machinery and transportation and other industries by the user's praise. The company continue to innovate, research and development of new products, design and manufacture safety, energy saving, environmental protection, intelligent features of fire-proof safe, powder coating environmental protection equipment and intelligent equipment engineering projects.

The company not only meet the needs of domestic customers, but also in Southeast Asia, the Middle East, Europe, North America, South America and other 27 countries occupied the market has won the favor of customers! The company always dedicated to our customers with the overall intelligent coating environmental protection system solutions and system services.