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Don't always blame final users if a problem occurs in industrial ventilation and dust collection systems

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Three sections in this blog post:
  1. There are reasons for "lack of maintenance"
  2. Ventilation systems need to be designed to include access for cleaning and preventive maintenance
  3. One example of the benefits of easy access for maintenance

Airvate engineers have worked with customers for many years and talked with plant management and maintenance guys a lot. We understand their feelings of embarrassment which are hard to mention.

There are reasons for "lack of maintenance"

Ventilation systems often are installed and then ignored until complaints or obvious problems force attention. This neglect may be due to insufficient knowledge and motivation. 

Final users normally don't employ any professional engineer to operate and maintain these dust collection and ventilation systems, especially for small and medium-sized ones as they are "secondary".

We hear many times that inadequate or no maintenance caused problems in the systems.

I personally believe it is unfair to blame the plant management and maintenance workers. 

As design engineers, manufacturers, or service engineers, we know more about the equipment and the whole system than the final users do. A lot of things are "common sense" to us while not known by the final users, and similarly we are not familiar with their production technology and their production line. Generally speaking, one will not "touch" a thing if he/she is not familiar with or lacks knowledge about it. If the thing is still running, naturally one would leave it alone. However, most of the time after a problem develops in its early stage, the maintenance guys find out that it is not that convenient to check, inspect, or try to maintain, so inspection or maintenance is thus often delayed.

If a lifter is needed to access a piece of equipment or a section of a system, or there is no platform for maintenance attached to the equipment, it is really inconvenient. Or, if a section of duct is thought to have clogged, one normally finds out there is no inspection door or Cleanouts on it or close to it (Cleanouts were supposed to be installed at elbows and for every 10 feet of duct length).

When we do fieldwork, we always hear a "bang bang" sound, and we know somebody is trying to break up a clog by "whacking the duct or hopper with a big stick or a hammer.”

Ventilation systems need to be designed to include access for cleaning and preventive maintenance


Without such access, the exhaust volume will deteriorate. Because of access difficulties and the many demands on their time, plant managers are sometimes neglectful in performing proper preventive maintenance. 

Recommendations to management should include realistic monitoring and maintenance plans, but where possible, it is prudent to employ designs that minimize the need for diligent maintenance efforts, especially for small and medium-sized operations.

Owners of systems should always follow design and maintenance recommendations.

One example of the benefits of easy access for maintenance


Three surveys measuring system exhaust air volume were conducted in a furniture manufacturing facility in one study.
A new ventilation system was installed for the first survey, resulting in an exhaust volume of 2900 cfm. Immediately after the first survey, the gasoline-powered fan was replaced by a smaller capacity electrically powered fan. 
Deterioration in the ventilation system was seen after seven years. Problems included clogged slots, paint chips and sawdust deposits in plenums, and a loose and frayed fan belt. The second survey indicated a reduction in exhaust volume to 1060 cfm. 
With the smaller capacity fan still in place, the system was otherwise upgraded to allow for easier access and maintenance was performed. The third survey showed that the ventilation system performance was better (exhaust volume improved to 2080 cfm). 

This study showed the benefits of designing for preventive maintenance and the necessity of keeping the ventilation system clean.

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