There are many ways to use storage in a compressed air system to
improve the performance and repeatability of production equipment. No
one method is a total solution. Some industry professionals will tell
you that storage is not required for certain types of
portable dental compressors.
The system, however, can not afford the impact on either performance
or operating costs. The alternative to applying storage is to operate at
higher pressures with more power all of the time in order to support
critical applications and the peak air demand experienced in the system.
There are six basic areas where storage should be properly engineered and applied in the system. These are:
Dedicated storage to improve the speed, thrust, or torque of an application.
Dedicated storage to protect a critical application from pressure fluctuations.
Dedicated storage to meter a high rate of flow application into the system.
General or overhead storage to support applications during the
transmission time to the supply side and to create transparency between
applications.
Control storage to support events in the system within an allowable pressure drop.
Off line, higher pressure air stored to support large system events and reduce peak electrical demand.
There are a few fundamental principles which must be discussed to understand when and how to apply storage in the system:
First, the article pressure in a system is the terminating pressure
at the actual inlet connection to the device. It is not at the regulator
or the header, so when someone says they have to have 90 psig for a
particular device, it is very important to know where they are
monitoring that pressure. This appears to be a small distinction but it
makes a huge difference in what is required to support the article.
Second, the purpose of the system is to deliver the required mass of air
to the article within the required time. Compressed air travels at a
limited velocity inside the system determined by the pressure
differential that exists. At 1 psid, this velocity is approximately 250
feet/second which means if the
dental air compressors
are more than 250 feet away, they won’t see an event which is less than
1 second duration until after it is complete. If you forget to consider
time, the value of these storage concepts will be very difficult to
grasp.
Third, the primary formula for applying useful storage or capacitance is
the capacity to store times the allowable pressure drop. For example,
if I have a 660-gallon tank and I can afford to allow the pressure to
drop 10 psi then the useful storage is calculated as: (660 gallons /
7.48 gallons/cubic foot) / 14.5 psia = 6.07sscf / psi x 10 psi = 60.7
scf of usable stored air.
Source:
http://www.chinadentalsupplier.com/2017/09/01/the-ways-about-how-to-use-storage-to-control-compressed-air-costs/
