Anti corrosion fan

Anti corrosion fans (corrosion-resistant centrifugal fans) are specifically designed to transport gases containing acidic and alkaline corrosives, relying on corrosion-resistant materials or coatings to resist smoke corrosion. They are widely used in chemical, acid washing, electroplating, waste gas treatment, desulfurization tower exhaust gas, laboratory exhaust gas and other scenarios to prevent shell and impeller from being corroded and perforated.

1、 Mainstream material classification (the first element of selection)

1. Fiberglass FRP anti-corrosion fan (most commonly used)

Resin+glass fiber integrated molding, resistant to hydrochloric acid, dilute sulfuric acid, and alkali mist; Light weight.

Good corrosion resistance; Not resistant to high temperatures, with a normal operating temperature of ≤ 80 ℃, and cannot withstand strong oxidizing media.

Suitable for electroplating, acid pickling workshops, acid and alkali waste gases.

2. PP polypropylene anti-corrosion fan

Plastic material, resistant to weak acids and bases; Lightweight and suitable for low pressure and room temperature.

High cost-effectiveness; The temperature cannot exceed 60 ℃, the rigidity is poor, and it is prone to deformation under high pressure conditions.

Suitable for small waste gas tower matching.

3. Stainless steel anti-corrosion fan (304/316L)

304: Weakly corrosive flue gas, damp chlorine containing low medium, ≤ 200 ℃

316L: In a chloride ion environment (seawater, desulfurization flue gas), it has stronger resistance to pitting corrosion

High temperature resistance and strength; The cost is higher, and concentrated hydrochloric acid environment will still corrode.

4. Carbon steel lined rubber fan

Q235 shell is lined with rubber inside, resistant to acid and alkali; Temperature ≤ 70 ℃, do not come into contact with sharp particles (which can easily scratch the lining layer).

Exhaust gas from desulfurization system, without hard dust conditions.

5. Titanium fan

The commonly used material is TA2 industrial pure titanium (mainstream in the industry), and TA9 titanium palladium alloy can be selected for special working conditions.

Super strong resistance to chloride ion corrosion; High temperature resistance, long-term usable temperature ≤ 260 ℃, far higher than fiberglass and PP plastic fans; Lightweight and high-strength, with low rotational inertia and low operating vibration; Long service life, stable operation for more than 10 years under suitable working conditions, but high material costs and expensive equipment prices.

Not applicable to hydrofluoric acid, concentrated high-temperature nitric acid, and fluoride gases.

2、 Structural characteristics

The casing, impeller, and air inlet are all made of corrosion-resistant materials; External bearing box (away from corrosive gases) to prevent corrosive gases from entering the bearings. Choose anti-corrosion fluororubber seals for sealing; Supporting accessories: anti-corrosion soft connection (fluorine tape), anti-corrosion air damper, anti-corrosion protective net.

3、 Common models

F4-72 and F9-19 anti-corrosion centrifugal fans are classic series in the industry.

4、 Core Features

1. The whole machine is resistant to acid and alkali corrosion, avoiding short-term corrosion and perforation of ordinary carbon steel fans

2. External bearing structure, isolating corrosive gases and protecting the spindle bearings

3. Multiple material options to choose from, suitable for different corrosive media and temperatures

4. Can be equipped with a complete set of exhaust ventilation solutions including frequency conversion, shock absorption, and noise reduction

5、 Key parameters for selection

1. Medium type: Hydrochloric acid/sulfuric acid/alkali mist/chlorine containing flue gas (specify corrosive components)

2. Medium temperature

3. Airflow, total pressure

4. Does it contain dust particles (particles can scratch the lining rubber and fiberglass)

5. Positive/Negative Pressure Operating Conditions

6. Material: FRP/PP/304/316L/lined adhesive

6、 Installation points

1. Fluororubber anti-corrosion soft connections are used for import and export, and ordinary canvas soft connections cannot be used as they are quickly corroded and damaged.

2. The pipeline is independently supported, and the weight of the pipeline does not pressure the fan.

3. The flange seal of the negative pressure anti-corrosion system must be tight to prevent the leakage of corrosive gases.

4. Fiberglass/PP fans are prohibited from impact, as brittle materials are prone to cracking upon impact.

5. Be well protected against rain, as some plastic materials may age when exposed to direct sunlight.

7、 Common faults

1. Shell perforation: incorrect medium selection, material not resistant to the corrosive gas

2. Rubber lining detachment: high temperature, particle erosion and scratching of rubber layer

3. Impeller pitting corrosion: chloride ion flue gas, using ordinary 304, causes pitting corrosion

4. Sealing failure, corrosive gas entering the bearing, rapid damage to the bearing