Is a 600W AC servo better than a matching asyncrounous single phase AC motor?

[A_Camera]

Typically, a servo motor has 30%-60% higher torque capacity and 30% better torque utilization with faster acceleration and deceleration, compared to asynchronous (induction) type motors. But is this really true?

The reason I ask this is that I just bought a 600W servo motor, which I will use in my DIY lathe as spindle motor, and I also consider buying a drill press which has a 500W single phase motor. This Guede GTB16/500 Vario, and the 500W motor is much larger than the 600W servo I have. I know much of that size is because of the large heat sink around the motor, but still... Could I replace the 500W motor with a 1kW servo and get a twice as powerful drilling machine which could be reversed and driven really slow? Would I get a similar, slightly more powerful machine if I'd replace the motor with a 600W AC servo?

[JohnHaine]

Induction motors have quite large diameter rotors and substantial stators so they are quite large. The "heatsink" doesn't contribute much in size. You could replace the motor in the drill press either with a servo plus its drive, or a 3-phase motor and VFD which would be the same size or smaller for the same power as the single phase fitted. Not sure which would be cheaper. Having variable speed and reverse on a drill is useful - machine tapping at low speed with instant reverse is very useful. I don't know why you are concerned about power for a drill, 500W should be more than you are likely to ever use with any drill you could fit in the chuck.

[A_Camera]

Thank you. Yes, I am concerned about the power because I don't want to just drill, but also use hole saws of large sizes in thick steel. My current machine is a Bosch PB 40 and that has a more powerful motor but it feels weak when doing metal works. I understand that 500W is plenty enough for wood and for ordinary use, but I like to think outside the box...

[JohnHaine]

You might be confusing power and torque. Using a large diameter holesaw really needs quite high torque but probably not much power. The ideal is a large reduction in the pulley system so the motor can operate near max torque geared down to the spindle.

[A_Camera]

Yes, I know that, but normally the higher the power the higher the torque at the same speed. Also, the pulleys are as they are, the question was more of a theoretical one, changing the motor 1:1 without any other re-design, like changing the pulleys and so on. My current PBD 40 can handle the hole saws I have used so far, but the motor of the PBD 40 is stronger, since it is 800W, unlike the planned machine, which is only 500W. Both have about the same lowest and highest RPM.