Pre Filter and Medium Folding Filter with Metal Frame

They are manufactured with nonwovens and glass fiber, etc. as the filtering materials. The wedge-shaped folds are used to enlarge the filtering area. They can also be manufactured to be a plate structure clamped with wire netting or supported with an inside metal framework and equipped with a metal outside frame. They have the characteristics of low resistance, long service life, can be washed, economy and durability, etc.

Application
They are generally used in the prefiltration of the central air conditionings and the centralized ventilation systems and the prefiltration of the gas turbines and the air compressors.

Structure
The inside structures of the filter are generally divided into keel framework and frame framework. The he characteristics of the keel framework include hardihood and uniform distribution of filtering materials, but its manufacture take time and energy. The characteristics of the frame framework include convenience in the exchanging of filter materials and time saving for its manufacture, but its strength is slightly poorer than that of the keel framework.

Filter material
Nonwovens, synthetic fiber, (imported) chemical fiber, (imported) glass fiber and nylon meshwork that can be washed can be used as the filtering materials. The most commonly used ones are nonwovens, glass fiber and nylon meshwork. Their efficiencies can be up to coarse efficiency or medium efficiency.