Compressed Air Required

Er, that information is the capacity of the compressor.

I Know the capacity of the compressor, to get 7 bar I will use 10 bar. Isn't it?

Another question appear which type is more sufficient Screw or Piston type.

My main Question is Regarding the flow I need 2395 l/min This is the actual need. without any margin.

Air demand is usually specified as free air, i.e. at about 1 bar absolute, 20°C. If your 2395l/min is free air this is the required compressor output, as PWSlack says. But someone new to compressed air and unfamiliar with the convention might calculate the demand at the 7 bar pressure, e.g. from piston displacement in an air cylinder. In that case need to multiply by 8 (assuming it's 7 barg = 8 bara) to get free air demand.

Also need to take account of demand pattern and type of compressor. If demand is continuous you might get away with compressor rated as above. But it's not unusual to rate a compressor at 2 x nominal, working start/stop, running 50% of the time, with a receiver sized to give reasonable max start frequency, say 6 starts/hour. If the compressor can unload you could use smaller one and receiver, but slightly more complicated controls.

Cheers...........Codey