A lot of time is spent sourcing and properly installing the right air compressor for a facility, setting the maintenance schedule and working out the intervals for regular oil sampling per the original equipment manufacturer’s (OEM’s) recommended service intervals.
However, there are other often overlooked components in an optimized compressed air system that are critical to helping get the most out of the compressed air system: Pipes, valves and fittings. If one part of the compressor system’s supporting components isn’t installed, operating or designed correctly, there is a major risk of lowered efficiency or, in the worst-case scenario, a shutdown.
Piping is a compressed air conduit
Pipes are the conduits that carry the compressed air to the process once it leaves the compressor. All compressors come with a discharge pipe connection sized by the manufacturer to have the proper and minimal pressure drop for the best compressor operation. Added to this connection is a manual (or automatic) shut-off valve. This disconnects the compressor from the compressed air system in times of maintenance.
The system piping to the plant after the shut-off valve, needs to be at least the size of the discharge connection at the compressor. The size of the pipe at the discharge of the compressor should never be reduced. Increasing the pipe size, however, is often beneficial to a compressed air system from a control reliability standpoint. The piping should also have the least number of 90° elbows as possible. In a good installation, sweeping piping radius bends are the best solution. This helps reduce the pressure drop every 90° elbow affords. As the piping connects to the main header, it is always good practice to connect the air at the top of the main header. If this is not done, then the pipe coming from the compressor can act as a “drip leg” and allow condensation to drain into the compressor.
In terms of piping materials, there are several options. Each comes with their own advantages and disadvantages. A compressed air specialist can help determine which type works for the specific application.
Aluminum piping is often used because it is lightweight, non-corrosive and easy to work with. Galvanized piping is sometimes used but is heavy and challenging to fit. Copper piping is also used but can be expensive. Older systems often have iron pipes which should be replaced. Over time, the residual water from the compressed air system can react with the iron pipes, causing a buildup of corrosion and reducing air flow.