Jaxian
Stainless
- Joined
- Feb 24, 2013
- Location
- Santa Cruz
So here is the situation. I have a new Doosan DNM5700. It has an air curtain system and through spindle air and some other air related features. Total air usage is rated at 8.83 cfm @ 80psi. A lot of that is the air curtain which was running any time the machine is on.
My present air compressor is an Ingersoll/Rand reciprocating type, Industrial model rated at 7.5hp/80gal/29cfm. I checked the flow and it is actually putting out that rated amount.
When the machine is on the air compressor kicks on every 4:30. This is with no tool changes and no air blow nozzles and no through spindle air running. It runs for 45sec to top off. I have a small 25x25 shop. It's sheet-rocked and the sound is annoying/distracting and loud as hell. Plus it is using lots of power and getting really worked out. Bigger issue, the voltage surges are also messing with the VMC when it kicks on. By that I mean it will crash the CNC if it's actually taking a cut or doing a tool change. It is single phase and not running on the RPC the VMC is.
So I was going to switch to a rotary unit for noise alone, but now the performance issues have made it more pressing. So I called Atlas/Copco and talked to a rep about what unit to get. Told them the air usage of the VMC and the cycling issue. Also told them my other air usage. My CNC lathe uses no air so no problem there. But I do use air tools once in a while. One person, so nothing major there. That is about it. So 90% of my air usage is the VMC.
They recommended a 5hp/53gal/16.6cfm rotary unit. So smaller than my present air compressor. They said because the rotary are designed to run with a 100% duty cycle any more than that is just wasting money. Also the unit wants to be on all time it was designed for that. As to the noise factor they said these small rotary units are about as loud as a dishwasher. So huge difference there.
So does that sound right? It's not a full featured unit (electronic controls, etc.) just a standard one but still isn't cheap. I want to make this sure this sounds right to people who are actually out there with some real world experience. Thanks for your input.
TL;DR Have a 7.5hp/80gal/29cfm reciprocating, Atlas/Copco says get a 5hp/53gal/16.6cfm rotary. Is this the right size?
My present air compressor is an Ingersoll/Rand reciprocating type, Industrial model rated at 7.5hp/80gal/29cfm. I checked the flow and it is actually putting out that rated amount.
When the machine is on the air compressor kicks on every 4:30. This is with no tool changes and no air blow nozzles and no through spindle air running. It runs for 45sec to top off. I have a small 25x25 shop. It's sheet-rocked and the sound is annoying/distracting and loud as hell. Plus it is using lots of power and getting really worked out. Bigger issue, the voltage surges are also messing with the VMC when it kicks on. By that I mean it will crash the CNC if it's actually taking a cut or doing a tool change. It is single phase and not running on the RPC the VMC is.
So I was going to switch to a rotary unit for noise alone, but now the performance issues have made it more pressing. So I called Atlas/Copco and talked to a rep about what unit to get. Told them the air usage of the VMC and the cycling issue. Also told them my other air usage. My CNC lathe uses no air so no problem there. But I do use air tools once in a while. One person, so nothing major there. That is about it. So 90% of my air usage is the VMC.
They recommended a 5hp/53gal/16.6cfm rotary unit. So smaller than my present air compressor. They said because the rotary are designed to run with a 100% duty cycle any more than that is just wasting money. Also the unit wants to be on all time it was designed for that. As to the noise factor they said these small rotary units are about as loud as a dishwasher. So huge difference there.
So does that sound right? It's not a full featured unit (electronic controls, etc.) just a standard one but still isn't cheap. I want to make this sure this sounds right to people who are actually out there with some real world experience. Thanks for your input.
TL;DR Have a 7.5hp/80gal/29cfm reciprocating, Atlas/Copco says get a 5hp/53gal/16.6cfm rotary. Is this the right size?
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