Understanding Pressure Drop and It’s Cost

Pressure Drop in you air compressor system

What Causes Pressure Drop?

Any type of obstruction, restriction, or roughness in the system will cause resistance to air flow and cause pressure drop. This can be the result of:

  • Undersized piping
  • Incorrect piping configuration (i.e. dead end piping instead of looped piping)
  • Undersized dryers and filtration
  • Poorly maintained filtration
  • Incorrect or excessive use of quick coupling connections
  • Extensive hose lengths

Effects of a Pressure Drop

Pressure drop is costing you money since in order to maintain the desired pressure at your point-of-use, you have to run your air compressor at a higher pressure than the minimum pressure needed to keep your factory operating. It takes more energy to produce air at a higher pressure, and energy costs money.

To put it in context:  If a machine only needs 90 PSI to function properly, but you have to operate your air compressor at 110 PSI in order to maintain the 90 PSI, this tells us that you have 20 PSI of pressure drop. As a rule of thumb, every 2 PSI of overpressurization costs you 1% in energy. 

Remedies

Minimizing pressure drop requires a methodical approach in design and maintenance of the system. Ways to minimize pressure drop are as follows:

  • Operate and maintain air filtering and drying equipment to reduce the effects of moisture, such as pipe corrosion.
  • Select after coolers, separators, dryers and filters having the lowest possible pressure drop for the rated conditions.
  • Properly design the air piping system – reduce unnecessary bends and pipe size changes.
  • Reduce the distance the air travels through the distribution system.
  • Reduce excessive hose lengths