Using Epoxy Coal Tar as Fan Anticorrosive Agent

Suzhou Brick and Tile Factory uses epoxy coal tar as an anticorrosive agent for the exhaust fan in the drying chamber's moisture removal system, with good usage effects.

1. Raw Material Formula (See Table 6-1)

2. Preparation Precautions：

(1) The softening point of 6101# epoxy resin is approximately 12℃. The boiling point of toluene is approximately 110℃. The boiling point of acetone is approximately 58℃. To accelerate the dissolution of epoxy resin and coal tar, appropriate heating may be applied during the preparation of Group A, but it should not be too high to prevent fire hazards.

(2) Mixing ethylenediamine with acetone generates heat up to 90℃, so water cooling must be used. Gradually pour acetone into ethylenediamine while stirring continuously.

(3) Coal tar must be heated to above 170℃ for processing and can only be used after cooling. This ensures the anticorrosive agent can withstand high temperatures of 100~120℃.

(4) During use, Group A and Group B are mixed evenly to form the two-component system, but they should not be mixed prematurely, as this may cause the anticorrosive agent to harden prematurely and become unusable.

3. Application Method

(1) Derusting Before applying the anticorrosive agent, remove oil and dirt from the metal surface, and use a wire brush or sandpaper for rust removal.

(2) Temperature The application temperature should not be too high; the coated object and ambient temperature around 15℃ is preferable. (In environments around 0℃, hardening takes nearly 20 hours after application; in environments around 30℃, hardening begins after 3 hours of application).

(3) Coating Method Use a brush to apply in crisscross patterns repeatedly, then brush over again after about 10 minutes to make the surface smooth and prevent pinholes that could affect the anticorrosive effect. The coating should not be too thick, as it may easily crack and peel off.

4. Usage Effects

The factory's No. 12 exhaust fan operates under acidic conditions of 35℃~45℃ and pH 3~4. Previously, the fan suffered severe corrosion after three months of use. After applying the epoxy coal tar anticorrosive agent, it has been in good condition for over a year. According to the brick and tile factory, this coating can withstand temperatures up to around 110℃.