Coating factories use many fans.

Booth exhaust fans.
Supply-air fans.
Oven circulation fans.
Baking oven exhaust fans.
VOC exhaust treatment fans.
Cooling fans.
Dust collection fans.
Air-conditioning fans.

These may be inconspicuous equipment.
Compared with coating robots, ovens, surface preparation equipment, or booths, they are sometimes considered later in investment planning.

However, fans are extremely important equipment in a coating factory.

They often operate for long hours and strongly affect electricity costs, the working environment, coating quality, and safety.

Do not select a fan by purchase price alone.
Even a cheap purchase becomes expensive equipment long-term if it continues consuming substantial electricity every day.

Assess coating factory fans by annual electricity costs and total costs, rather than purchase price alone.

1. Fans are important equipment that moves air through the factory

Airflow is extremely important in a coating factory.

Booths remove coating mist, odors, and solvent vapor.
Drying ovens circulate hot air to dry and cure the film.
Baking ovens heat under defined conditions while limiting temperature variation.
Exhaust treatment systems deliver air containing VOCs or odors to treatment equipment.
Supply-air systems deliver outside or conditioned air to the workplace.

Fans move all this air.

Insufficient fan capacity prevents the required airflow.
Insufficient airflow may leave mist, odors, heat, or solvent vapor behind.
Excessive airflow, conversely, increases electricity costs and air-conditioning load.

Fans are therefore more than auxiliary equipment.
They are fundamental equipment supporting quality, safety, and energy conservation.

2. Judging by purchase price alone overlooks annual electricity costs

The prices in a fan quotation are easy to understand.

Fan price.
Motor price.
Installation costs.
Control panel costs.
Construction costs.

However, the largest differences often arise in operating costs after purchase.

Booth and exhaust-system fans in particular may run throughout the day.
They may operate for 8 hours, 10 hours, or sometimes nearly 24 hours a day.

For such equipment, a small efficiency difference becomes a large annual electricity cost difference.

For example, a low-priced fan with poor efficiency raises monthly electricity costs.
If this continues for years, the operating cost difference may exceed the difference in initial price.

Assess fans by electricity costs throughout their operating life as well as their price at purchase.

This is called assessing life-cycle cost.
Life-cycle cost is the total cost including electricity, maintenance, repairs, and replacement, as well as purchase.

3. Check airflow volume and static pressure when assessing fans

The first item to check is airflow volume.

Airflow volume indicates how much air can be moved in a given time.
For a booth, the important question is whether the required exhaust volume can be achieved.
For an oven, it is whether the airflow needed for hot-air circulation can be achieved.

However, airflow volume alone is insufficient.

Static pressure is another important factor.
Put simply, it is the pressure used to push or draw air against resistance from ducts, filters, bends, and equipment.

A fan alone may appear to provide sufficient airflow, yet fail to deliver it once connected to the actual equipment.
Duct resistance, clogged filters, piping bends, or resistance in exhaust treatment equipment can cause this.

Check the following items.

• Required airflow volume
• Required static pressure
• Duct length
• Duct bends
• Filter resistance
• Exhaust treatment equipment resistance
• Actual air velocity
• Motor rating
• Current
• Noise
• Vibration

Assess whether the fan delivers the required performance within the entire system, as well as its standalone performance.

4. Clogged filters and duct resistance increase fan load

The air path is important as well as the fan itself.

For example, clogged filters restrict airflow.
Accumulated contamination in ducts also increases resistance.
Excessively long ducts, too many bends, or small cross-sections also increase fan load.

This causes the following problems.

• Failure to achieve required airflow
• Higher electrical load on the fan
• Motor overload
• More noise
• More vibration
• Residual mist or odors
• Weaker booth extraction
• Worse oven temperature distribution

Even an energy-efficient fan cannot deliver its intended performance with poor filter management or duct design.

Consider the air path as well as the fan when planning energy conservation.

5. Variable-frequency control runs the fan only as much as needed, when needed

Variable-frequency control is often used to save fan energy.

A variable-frequency drive adjusts motor speed.
Instead of always running the fan at full speed, it adjusts speed to the required airflow.

A coating factory does not necessarily need the same airflow at all times.

High-production periods.
Low-production periods.
Setup changes.
Breaks.
Manual spraying.
Automatic coating.
Standby periods without coating.

The required airflow may change with these states.

However, installing a drive does not automatically make everything better.
A booth has a minimum airflow needed for safety.
An oven needs circulation airflow for temperature distribution and drying quality.
Exhaust treatment equipment needs airflow that meets its treatment conditions.

Even with variable-frequency control, determine the permissible adjustment range after checking quality, safety, and equipment conditions.

A drive is not simply a tool for stopping a fan.
It delivers only the airflow that is needed.

6. Noise is a cost to the working environment

Noise matters as well as electricity costs when assessing fans.

Fans, compressors, exhaust equipment, conveyors, and other equipment generate noise.
Excessive fan noise burdens operators.

Noise is more than an annoyance.

Operators become tired more readily.
Conversations or instructions are difficult to hear.
Abnormal sounds become harder to detect.
Concentration declines.
Safety checks become more difficult.
Long work periods become stressful.

Noise therefore imposes a cost on the working environment.

Low-power or efficient fans may also reduce noise in some cases.
Although the same effect cannot be expected in every case, check noise alongside electricity costs when replacing a fan.

Check the following items.

• Fan noise level
• Noise at the operator’s position
• Noise from ducts
• Vibration noise
• Motor noise
• Abnormal noise
• Need for soundproofing measures
• Effects on conversations or instructions

Fan improvements improve the working environment as well as saving energy.

7. Whether existing equipment can be retained is also important

When considering fan replacement, check how it fits into the existing equipment as well as its performance.

Even a high-performance fan may require substantial work if it does not fit existing foundations, ducts, control panels, motors, or installation space.

Extensive work creates the following problems.

• Higher installation costs
• Longer line downtime
• Effects on production plans
• Required duct modifications
• Required electrical capacity reviews
• Additional safety measures
• Higher construction risks

Replacement using existing foundations or ducts may reduce the schedule and costs.

Vietnamese factories often have limited time in which production can stop.
For fan replacement, check site fit, installation duration, and downtime as well as performance.

Compatibility with the actual site is extremely important, alongside catalog performance.

8. Do not address insufficient airflow solely by increasing motor rating

Booths or exhaust systems may have insufficient airflow.

Extraction is weak.
Mist escapes.
Odors remain.
Operators notice poor air quality.
Oven circulation is weak.
Exhaust treatment is unstable.

These situations may prompt a simple switch to a larger motor or fan.

However, check the following before immediately increasing capacity.

• Are filters clogged?
• Has contamination accumulated in ducts?
• Is duct resistance excessive?
• Are dampers appropriately open?
• Is supply air insufficient?
• Is contamination on fan blades?
• Have motors or belts deteriorated?
• Has added equipment increased resistance?

If insufficient airflow originates in ducts or filters, increasing motor rating may not solve the underlying problem.
It may merely increase electricity costs.

Check the entire air path before suspecting insufficient fan capacity.

9. Make annual fan electricity costs visible

The first step in fan improvement is making annual electricity costs visible.

Check the following items.

• Motor rating
• Actual current
• Operating hours
• Operating days
• Electricity tariff
• Operating pattern
• Full-capacity operating hours
• Standby operating hours
• Periods when stopping is possible
• Feasibility of variable-frequency control

This information allows an estimate of annual fan electricity costs.

Look at a list of the factory’s main fans, rather than just one fan.

Booth exhaust fans.
Supply-air fans.
Oven circulation fans.
Exhaust treatment fans.
Cooling fans.
Dust collection fans.

Knowing which fans consume the most electricity makes improvement priorities easier to define.

Start energy conservation by making consumption visible, rather than by intuition.

10. Items to check during fan replacement

Check the following items when replacing a fan.

Performance

• Required airflow volume
• Required static pressure
• Motor rating
• Efficiency
• Noise
• Vibration
• Operating temperature
• Operating environment
• Need for explosion protection, corrosion resistance, or similar features

Operation

• Annual operating hours
• Operating pattern
• Need for full-capacity operation
• Feasibility of airflow adjustment
• Feasibility of variable-frequency control
• Maintenance frequency

Compatibility with existing equipment

• Foundation dimensions
• Duct connections
• Installation space
• Control panels
• Power supply capacity
• Electrical receiving and transformation equipment
• Inspection space
• Delivery and access route

Economics

• Purchase price
• Installation costs
• Annual electricity costs
• Maintenance costs
• Downtime
• Payback period

Quality and safety

• Effects on booth air velocity
• Effects on the working environment
• Effects on odors and mist
• Effects on oven temperature distribution
• Effects on exhaust treatment performance

Evaluate the fan within the entire coating process, rather than as a standalone unit.

11. CoatureVietnam’s approach to fan improvements

CoatureVietnam does not consider fan improvement simply as equipment replacement.

First, we check the shop floor.

Which fans are installed?
Which equipment uses them?
How many hours do they operate?
What airflow is required?
Is actual airflow sufficient?
What is the resistance from filters and ducts?
Is there noise or vibration?
Do operators notice insufficient extraction or excessive airflow?
What are annual electricity costs?

We then consider the direction of improvement.

• Reviewing operating hours
• Improving filter management
• Reducing duct resistance
• Variable-frequency control
• Improving fan efficiency
• Improving motor efficiency
• Noise countermeasures
• Replacement that retains existing equipment where possible
• Reducing air-conditioning load
• Improving the working environment

Fans constantly work behind the scenes in a coating factory.
Reviewing them therefore improves quality, safety, and the working environment as well as saving energy.

Conclusion

Do not judge coating factory fans by purchase price alone.

Fans operate for long hours.
Consider annual electricity costs, noise, maintainability, compatibility with existing equipment, and effects on the working environment.

A low-priced fan becomes expensive long-term if electricity costs are high.
Insufficient airflow leaves mist or odors behind.
Excessive airflow increases electricity costs or air-conditioning load.
High noise burdens operators.
Poor compatibility increases installation costs or downtime.

Fans support the air environment in a coating factory.
Air directly affects coating quality, workplace safety, the working environment, and energy conservation.

CoatureVietnam reviews fans as important equipment supporting quality and the working environment, rather than simple equipment components.
Deliver the required airflow to the required locations with the necessary power and without burdening operators.
This is the basis of fan improvement in a coating factory.

Coating the Future with Science and Care
Reviewing fans is an inconspicuous but substantial opportunity for improvement.