Instrument Air Utiity Report
Instrument Air Utiity Report
(OP)
Guys,
I need your advise
I am preparing utility report for instrument air. In the form I have a column for flow rates,but I don't know how spesify flowrate for pneumatic actuators ?
I need your advise
I am preparing utility report for instrument air. In the form I have a column for flow rates,but I don't know how spesify flowrate for pneumatic actuators ?





RE: Instrument Air Utiity Report
The spec sheet for the Moore M760 (page 2) says:
Air consumption
Standard Spool = 0.5 scfm
Low Gain Spool = 0.5 scfm
High Flow Capacity Spool = 1.0 scfm (typical)
The Siemens PS2 uses air only on active movement, it uses no air in a static state, so its consumption is negligible.
PS2 Spec sheet says
Power consumption in the
controlled state
< 3.6*10^-2 Nm³/h (0.158 USgpm)
which is appears to be babel translation from German,
so let's assume they mean air consumption, not power consumption and one doesn't measure air consumption in units of gallons.
Assuming the original metric value is correct,
3.6*10^-2 Nm³/h
meter^3 per hour = 35.314667 feet^3 per hour
0.036 m3/h = 1.27 cfh = 0.021cfm
RE: Instrument Air Utiity Report
Your air compressor will have the same kind of rating of standard cubic feet per minute at a fixed discharge pressure, typically 90 to 100 psig. If you are at high altitute or in an area where you have extra capacity air filters on the air compressor, you may loose some capacity.
As danw2 states yousome instruments only bleed air while in motion. For those you will have to assume some percentage of the time they will move. For a report I'd assume 30%, for design I'd assume 90%. add up all your SCFM's for your users and compare with the air compressor SCFM to get utilization rate.
RE: Instrument Air Utiity Report
After all above steps, you calculated only instrument air. Some margins need to be added over the top for Air leakage, Future development, and plant air only if plant air comes from the same compressor. 10-15% for air leakage and 30- 40% for Future aren't unusual. If insufficient info available, assume plant air identical to instrument air. Plant air less than 200 SCFM is unusual!
Sun