Understanding the Relationship between Pressure Drop and an Increase in Operating Costs

Compressed air is one of the most expensive energy sources in any plant. With the rising costs of electricity maintaining efficiency to minimise operating costs is critical for any compressed air user. One of the biggest issues for compressed air users and a major source of decreased efficiency is pressure drop.

Pressure drop occurs when there is a loss of pressure from the compressor discharge to the actual point-of-use. When pressure drop occurs most compressed air users compensate by increasing the pressure at the compressor. By increasing the pressure at the compressor rather than addressing the issues causing the pressure drop it results in the compressor working harder, reducing output, consuming more electricity and significantly increasing the systems operating cost.

What causes pressure drop?

Pressure drop can be caused by any type of restriction, obstruction or roughness in the compressed air reticulation system causing a restriction of air flow. Once air flow is restricted in any way it results in pressure drop. The main causes of pressure drop can be categorised into 2 sides:

1)Supply Side

2) Demand Side

1)    Supply Side Pressure Drop

The supply side of the system involves the generation of compressed air such as the compressor and ancillaries. The major causes of pressure drop in the supply side are:

  • Air/lubricant separators blocked – although this will show up through higher power bills.
  • Aftercoolers undersized
  • Air filters undersized or blocked
  • Condensate separators
  • Air Dryers undersized

To minimise pressure drop in the supply side of a compressed air system ensure all compressors and ancillary equipment are correctly sized and selected to suit your particular application and ensure all equipment is regularly monitored and serviced to ensure maximum efficiency is maintained.

2)    Demand Side

The demand side of a compressed air system involves the reticulation system (piping) and the points-of-use. The major causes of pressure drop in the demand side of a compressed air system are:

  • Undersized piping
  • Unsuitable piping material
  • Poor piping layout
  • Air leaks in the reticulation system
  • Undersized or leaking hoses

To minimise pressure drop on the demand side of the compressed air system care should be taken in the selection of compressed air piping size, material and layout to ensure that compressed air will travel through the distribution system with minimal restriction taking the shortest path possible to its end-use application. A focus on not only current demand but future growth in demand for compressed air should be taken into consideration to avoid future pressure drop problems. Also a regular air leak maintenance plan should be in effect to minimise pressure drop and loss of efficiency.

If you are experiencing problems with pressure drop or planning a new installation contact us for expert advice on obtaining maximum efficiency for your compressed air system.

Call us on 1300 098 201 or simply fill in the ‘Enquiry Form’ on this page.