FAW Group Project: Precision Bag Filtration System for Automotive Pre-treatment and E-coat Lines
Project Background:
China FAW Group, the cradle of China's automotive industry, maintains exceptionally high standards for its production processes. In automotive manufacturing, the painting process directly determines the vehicle's appearance quality and anti- corrosion performance. During the pre- treatment (degreasing, phosphating) and Cathodic Electrodeposition (CED) stages, fine metal chips, dust, and impurities accumulate in the circulating tank liquids. If these impurities adhere to the car body, they cause defects such as paint seeds and craters. Consequently, FAW introduced Unite's high- precision multi- bag filtration systems into its modern painting plants.
Core Challenges:
High Surface Quality Standards: Automotive painting is extremely sensitive to particulate impurities, requiring the filtration system to stably intercept fine particles larger than 5-25μm to ensure a smooth paint film.
High- Flow Circulation Treatment: Painting tanks have massive volumes and require high- frequency circulation, demanding filters with ultra- high throughput and low- pressure drop characteristics.
Maintenance Convenience: With the extremely fast pace of automotive production lines, bag replacement must be simple and quick to minimize production downtime.
Equipment Durability: Degreasing and electrocoating liquids possess chemical activity, requiring filter vessels and components to offer excellent corrosion resistance.
Our Solution:
Tailored to the rigorous conditions of FAW's painting lines, we provided an integrated multi- bag precision filtration solution:
Quick- Open Multi- Bag Filters: Utilizing stainless steel (SS304/316L) multi- bag structures per unit. Equipped with unique quick- open mechanisms (V- clamp or davit arm), allowing a single operator to complete bag changes within minutes, significantly boosting O&M efficiency.
High- Efficiency Depth Filter Bags: Utilizing high- precision, high- dirt- holding capacity polypropylene (PP) or polyester (PE) needle- felt bags. The fully welded structure and patented seal rings eliminate bypass risks, ensuring 100% filtration precision.
Low- Resistance Internal Structure: CFD- optimized internal flow designs reduce liquid impact, ensuring uniform cake distribution inside the bags and extending their service life.
Integrated Skid- Mounted Sets: The filters integrate inlet pressure gauges, vent valves, and drain valves. The entire unit undergoes sanitary- grade polishing, meeting the automotive industry's cleanliness specifications for equipment.
Customer Value & Results:
Since the commissioning of these bag filtration systems on FAW's painting lines, tank liquid cleanliness has significantly improved, leading to an approximately 20% reduction in paint rework rates caused by impurities. The system's high throughput and long- life bags have effectively shortened maintenance downtime and lowered operational consumable costs. FAW highly commended Unite's expertise in filtration precision control and quick- open structural design. This solution has since become standardized auxiliary filtration equipment for multiple production lines of their independent and joint- venture vehicle brands.
