I got a question from a friend today, he s changing an old stacking conveyor from a electric to a gas motor and wondering what the hp conversion is. from what I have read on line this morning it is roughly 1 -1.5 electric to 2 gas. ie. 5 hp electric will do the same as 10-12 hp gas. the conveyor is 80 feet long, 24 inch belt, with a 30 hp electric and a 40:1 reduction.. roughly that means I need around a 60 hp gas motor is this correct?
Yes, that's what I've always seen. But the 2:1 ratio is more for small gas engines which are more "optimistically" rated than a larger gas or diesel engine. An industrial gas engine at 60hp or diesel at even 40hp should be close.
Horsepower is horsepower, more or less. The problem is, electric motors will develop a hell of a lot more torque to start a load moving, and every now and then grunt to keep a load moving. Gas engines especially and the smaller high revving diesels don't have the torque to deal with heavy startup demand or the odd overload, they just give up. I'd go hydraulic off the gas or diesel power unit with a load sensing pump and horsepower limiting. But that's just me.
Yair . . . This could be a can of worms. Okay you need (say) 60hp. At what revolutions? It will be a fair lump of an engine. For that kind of continuous duty it would be nice to run at generator speed or less than 2000 revs. You will need a governor and an industrial clutch and a radiator and there will be cutting and shutting to put it all together . . . I think a 60/70kva genset is looking better all the time. You could go a smaller generator if the motor was driven by a variable frequency drive as the load can be backed off for starting. Just some thoughts. Cheers.
Well now, why didn't I think of that? Much better idea!