a high-quality filter must achieve a filtration efficiency of over 99% for 5-micron particles
First and foremost,This is especially vital in dusty environments like mines, construction sites, and deserts, where 5-micron particles are abundant.
Selecting premium filter paper is the prerequisite. High-quality filter paper features uniform pore sizes and small diameters. For instance, the filter paper used in our factory is the Ahlstrom model AB8438H AD. With an average pore diameter of 44 microns, this paper creates a highly effective filtration barrier once pleated.
the production technology and process of air filters are also very important.
1. Air Filter Production Process – Filter Paper Folding Process Unwinding, humidifying: Note that the humidifying device uses steam humidification, with a steam temperature of 80–150°C. Creasing: Roller pressing is applied to the surface of the filter paper. Folding: Arranged in a W or V shape. The angle of the V-shape should be controlled within 30 degrees, aiming to increase the filtration area and achieve high filtration performance and high dust holding capacity. The above constitutes the filter paper treatment process for air filters.
2. Air Filter Production Process – Glue Injection Process For most PU (polyurethane) glue injection processes, two-component glue (A and B) is typically used, commonly applied in heavy-duty truck air filters and construction machinery air filters. The mixing ratio must be strictly controlled – 4:1 is recommended – and the glue must be fully rolled and stirred before use to prevent sedimentation that may lead to uneven curing. During the glue injection process, the glue temperature error should be controlled within ±1°C. The glue injection volume should be sufficient to penetrate the base of the filter paper but must not overflow and block the air passages. High-precision molds are used to reduce bubble formation and ensure more accurate dimensions of the air filter. Currently, the production processes in our factory are completed with automated equipment, which greatly improves product quality standards.

