How to choose the right fan in glass manufacturing industry?

Choosing a suitable fan in the glass manufacturing industry needs to be comprehensively evaluated from multiple dimensions in close combination with the technological characteristics of the whole glass production process (such as high temperature, dust, corrosive gas, high cleanliness requirements, etc.), equipment operation requirements and energy-saving and environmental protection objectives. The following are the specific selection logic and key considerations:

First, make clear the "application scenario": the requirements of different process links are very different.

In the glass manufacturing process (raw material preparation → melting furnace → molding → annealing → deep processing), the functions of fans (ventilation, dust removal, cooling, combustion-supporting, waste gas treatment, etc.) are different, and the core requirements are completely different. It is necessary to lock the specific application scenarios first:

Key demand points of fan core function in process link

Raw material preparation (crushing/screening) raw material dust collection, workshop ventilation, high negative pressure, dust wear resistance and easy cleaning.

Combustion-supporting air transportation, smoke exhaust, high temperature resistance (200-800℃), smoke corrosion resistance and stable wind pressure in glass melting furnace.

The equipment in the molding workshop (such as float) is cooled (such as the circulation of protective gas in the tin bath), and the environment is ventilated with low noise, clean and free from oil pollution (to avoid polluting the glass surface).

The annealing kiln has high temperature control accuracy (stable wind pressure/air volume) and medium temperature resistance (100-300℃) for hot air circulation and tail gas discharge.

Deep processing (coating/cutting) workshop is clean and ventilated, and waste gas (such as coating waste gas) is treated with high cleanliness (no particles fall off) and chemical corrosion resistance.

Second, the core technical parameters: accurately match the process requirements

After defining the scene, it is necessary to confirm the core parameters of the fan first to avoid low efficiency and frequent failures caused by "parameter mismatch":

1. Air Volume and Air Pressure.

Air volume: calculated according to the workshop volume and dust/flue gas output (for example, the raw material workshop needs to be estimated according to "air exchange times of 10-15 times/hour", and the furnace flue gas extraction needs to be calculated according to the fuel combustion amount), and 10%-20% allowance should be reserved to deal with process fluctuation.

Wind pressure: pipeline resistance (such as long-distance air ducts, valves and filters) needs to be overcome. For example, a dust collector needs to be installed in the flue gas system of the furnace, and the wind pressure needs to cover the resistance loss of the dust collector (usually 500-1500Pa).

2. Temperature Resistance (temperature resistance)

Low-temperature scene (such as cooling in molding workshop and ventilation in deep processing): conventional fans (medium temperature ≤80℃) can be selected, such as centrifugal fans and axial fans.

Medium-temperature scene (such as hot air circulation in annealing kiln): it is necessary to choose a medium-temperature resistant fan (100-300℃), and the motor should adopt high-temperature resistant insulation grade (such as class H), and the heat dissipation structure should be added.

High-temperature scene (such as furnace combustion-supporting air and flue gas exhaust): Special high-temperature fan (with temperature resistance of 300-1000℃) must be selected, impeller and casing should be made of high-temperature alloy materials (such as Q235 heat-resistant steel and stainless steel 310S), and bearings should be equipped with water cooling/air cooling system to avoid high-temperature damage.

3. Wear resistance and corrosion resistance

Wear resistance: In the process of raw material preparation and furnace dust, the fan should deal with high-concentration dust (such as quartz sand dust), and "wear resistance design" should be selected: the impeller should be made of wear-resistant materials (such as high chromium cast iron and wear-resistant covered electrode surfacing), and the casing should be lined with wear-resistant ceramics/rubber. At the same time, the intake structure should be optimized to reduce eddy current wear.

Corrosion resistance: If sulfur-containing flue gas (such as fuel sulfur) and chemical waste gas from coating workshop (such as fluoride and organic matter) are involved, fans made of corrosion-resistant materials should be selected: stainless steel (304/316L) and glass fiber reinforced plastic (FRP) for impeller/casing, and corrosion-resistant rubber (such as fluororubber) for seals to avoid corrosion and rust of metal parts.

4. Cleanliness and noise

Cleanliness: The molding workshop (such as float glass tin bath) and coating workshop need to avoid oil pollution or particle pollution on the glass surface caused by fans. Oil-free lubricating fans (such as magnetic suspension fans, air suspension fans and mechanical bearing lubricating oil) should be selected, or centrifugal fans with fully sealed structure should be adopted, and high-efficiency filters (such as HEPA screens) should be installed at the fan inlet.

Noise: Glass workshops usually meet the industrial noise standard (≤85dB). Low-noise fans (such as magnetic levitation fans with noise ≤75dB) can be selected in crowded areas such as molding and deep processing, or noise can be reduced by installing silencers, sound insulation covers and shock absorption pads.

3. Type selection of fan: match the optimal model according to the scene.

The characteristics of different fan types are significantly different, so it is necessary to choose according to the above requirements:

Matters needing attention in application scenarios of core advantages of fan types

Centrifugal fan has high wind pressure, stable air volume, temperature resistance/corrosion resistance, large space for transformation, dust removal of raw materials, smoke extraction of melting furnace and hot air circulation of annealing furnace should be selected according to "working point falls in high efficiency area" to avoid surge.

Axial flow fan is not suitable for long-distance and high-resistance pipelines because of its low air volume, small size, convenient installation, workshop ventilation and molding workshop cooling (low-resistance short duct scene).

Magnetic suspension fans are oil-free and friction-free, energy-saving (30%+ compared with traditional ones), low noise, clean workshop ventilation, low dust and low corrosion scenes (such as coating waste gas treatment), with high initial investment, and are suitable for long-term operation (≥ 8,000 hours/year).

Air suspension fan is oil-free, resistant to high temperature (≤200℃) and fast in response. Medium temperature clean scenes (such as auxiliary ventilation of annealing kiln and aeration of sewage treatment) are not suitable for high dust and high corrosion environment (easy to block suspension gap).

The high-temperature special fan is resistant to temperature ≥300℃ and high-temperature deformation. The combustion-supporting air and high-temperature flue gas in the furnace need to be regularly checked for wear and tear of high-temperature parts, which leads to high maintenance cost.

Fourth, additional considerations: energy saving, maintenance and adaptability

Energy saving: Glass manufacturing is a high energy consumption industry. As the main power equipment, the energy saving directly affects the operating cost. Give priority to energy-efficient and energy-saving models:

The motor adopts the first-class energy-efficient motor (IE4 standard);

Adopt frequency conversion control (automatically adjust the air volume/wind pressure according to the process load, for example, when the dust volume in the raw material workshop fluctuates, the frequency conversion fan can save 20%-50% energy consumption);

Magnetic suspension and air suspension fans save more than 30% energy than traditional roots fans and centrifugal fans, and are suitable for long-term continuous operation scenes.

Maintenance convenience: glass production is mostly continuous operation, and fan failure will lead to production stoppage, so it is necessary to choose an easy-to-maintain model:

Give priority to the fan with simple structure and easy disassembly (for example, the impeller and bearing box of centrifugal fan can be disassembled separately);

Key components (such as bearings and seals) shall be of common models, which is convenient for purchasing and replacing;

If conditions permit, fans with "on-line monitoring function" (such as temperature and vibration sensors) can be selected to give early warning of faults in real time and reduce downtime.

System adaptability: the fan shall be matched with upstream and downstream equipment (such as dust collector, heat exchanger and pipeline);

The size of the inlet and outlet of the fan should be consistent with the diameter of the pipeline to avoid resistance loss caused by excessive diameter change;

If the fan is used in the flue gas system, it should match the handling capacity of heat exchanger (cooling) and dust collector (impurity removal) to avoid insufficient pumping caused by "small fan with large system" or energy consumption waste caused by "large fan with small system".

Summary: Three-step selection process

Scenarios: define which link of the fan is used in glass manufacturing (such as furnace flue gas and raw material dust removal), and determine the core requirements (temperature resistance, corrosion resistance and cleanliness);

Calculation parameters: calculate the required air volume and wind pressure according to the process quantity, and determine the temperature resistance and corrosion resistance grades in combination with environmental conditions;

Type selection: match the optimal fan type according to the parameters (such as special centrifugal fan for high temperature and magnetic suspension fan for clean), and give consideration to energy saving and maintenance.

Through the above logic, it can be ensured that the selected fan can not only meet the technological requirements of glass manufacturing, but also realize efficient, stable and low-cost operation.