Torque & rpm

Dear Engineers,

Asslam u Alaikum(May peace be upon all of you)

I have machine A, rotates at 3000 rpm and required torque to rotate is 10 NM.
I want to operator this machine with an other machine B(motor) of 1500 rpm which can gives the torque of 7 NM max.

1. Can I operate it by using 2 gears,1 to shaft of machine A and 2nd to the shaft of machine B?
2. How can i calculate the gears size to meet the torque and rpm?
3. will the load of machine B increase in this case, even using gears? bc I don't want big difference in current.

regards

zafar

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mfb
Mentor
If machine A requires 3000rpm with a torque of 10Nm, it needs a power of 3000rpm*10Nm*2pi = 3.1kW.
Your motor can deliver a maximum of 1500rpm*7Nm*2pi = 1.1kW. Gears cannot produce energy out of nowhere - there is no way to operate machine A with your design values with motor B. You have to reduce revolution frequency or torque, or use a more powerful motor.

rcgldr
Homework Helper
For an idealized motor, max torque occurs at zero rpm (stalled) and max rpm occurs with zero torque (no load). Maximum power occurs at 1/2 max rpm with 1/2 the max torque. As mentioned above, you need a more powerful motor.

If machine A requires 3000rpm with a torque of 10Nm, it needs a power of 3000rpm*10Nm*2pi = 3.1kW.
Your motor can deliver a maximum of 1500rpm*7Nm*2pi = 1.1kW. Gears cannot produce energy out of nowhere - there is no way to operate machine A with your design values with motor B. You have to reduce revolution frequency or torque, or use a more powerful motor.

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