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Active Contributor

Join Date: Apr 2012
Posts: 11

# How to Select the Motor Power

04/17/2012 1:17 AM

we are designing one rotating equipment .

Gear motor is used to rotate the shaft. shaft is placed horizontal . bearing is placed two end the shaft .

centre of the shaft 2000 kg is acting perpendicular to the shaft.

gear motor out put speed is 1 rev per minute .

how to select the power (kw ) of the motor

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Guru

Join Date: Oct 2008
Posts: 40528
#1

### Re: how to select the motor power

04/17/2012 1:24 AM

You will select the power of the motor based on the calculations you did to arrive at the power requirements of the system you are designing. You give no useful information here.

Hire an engineer with the correct experience for the job. Looks like you need one badly.

Active Contributor

Join Date: Apr 2012
Posts: 11
#2

### Re: how to select the motor power

04/17/2012 1:28 AM

what information you need to calculate the power

Guru

Join Date: Oct 2008
Posts: 40528
#3

### Re: how to select the motor power

04/17/2012 1:30 AM

I'm not going to do your job for you.

Hire an engineer.

Guru

Join Date: Jun 2010
Posts: 1301
#4

### Re: how to select the motor power

04/17/2012 1:39 AM

I don't know how to reply politely to your question, but, frankly, you shouldn't be designing equipment if you don't understand the basics of mechanics, and this is one of the basic, if not the most basic, principles of power. Besides, you haven't given enough information for anyone to calculate the power needed. Not only do you not know how to perform the basic calculation, but apparently you don't know what data is required. I am hoping that you are a beginning student and will therefore soon cover this in class.

Active Contributor

Join Date: Apr 2012
Posts: 11
#5

### Re: how to select the motor power

04/17/2012 1:46 AM

i do not know . why you escape from my question.

either you do not know answer or not .

if you do not knowm means do not reply . i will take care of it . already i have sent my calculated sheet for you reference .

i am expecting only guidance on my query. but you are not in the position to answer .

Score 2 for Off Topic
Active Contributor

Join Date: Apr 2012
Posts: 11
#6

### Re: how to select the motor power

04/17/2012 1:52 AM

pleae find the calculated sheet .

 Design Calculation for power Date:17-Mar-12 S.no Parameter Specification Unit Remarks 1 Load (F) 14715 N 2 Speed (N) 1.2 r/min 3 Radius (R) 0.035 m 4 Velocity(V) 0.004396 m/s 5 Torque (T) 0.06468714 N.m 6 Power(P) 0.099672384 KW 7 Power(P) with FOS 2 0.199344768 KW Formaula 1 Velocity (V) = ∏xDx(N/60) m/s 2 Torque (T) = (FxV)/1000 N.m 3 Power (P) = NxT/9550 KW Speed:- (N) Customer input = 50 -60 Second /360 degree 60 Seconds/360 degree = 1 r/min 50 Seconds/360 degree = 1.2 r/min load :- (F) Micra Body 600 Mounting Frame 139 Mounting Frame Support 50 Bearing,Coupling& other Accessories 10 Human (4 persons-Approx.Each 100 kg) 400 Total 1199 kg Appro. Load taken with FOS 1500 Kg Radius (R) Shaft Dia 70 mm Flange Dia 160 mm Imaginary Outer Dia of vehicle 2050 mm Radius (R) Shaft Radius 35 mm
Guru

Join Date: Oct 2008
Posts: 40528
#7

### Re: how to select the motor power

04/17/2012 2:01 AM

There you go. You can take it from here.

Or, do you want us to send it to motor suppliers for you?

Score 1 for Off Topic
Active Contributor

Join Date: Apr 2012
Posts: 11
#8

### Re: how to select the motor power

04/17/2012 2:28 AM

if our calculation is correct .

power approxi 0.2 kw is comming.

so we can go for 0.4 kw motor .

is it correct .

we can select the motor supplier . why you want to strain your self

Score 1 for Off Topic
Power-User

Join Date: Dec 2010
Posts: 379
#13

### Re: how to select the motor power

04/18/2012 11:22 AM

As your project involves human being, it is sincere suggestion that you hire a good engineer to do calculations for your project.

Guru

Join Date: Jun 2010
Posts: 1301
#9

### Re: how to select the motor power

04/17/2012 2:29 AM

In the immortal words of C.B., "Good grief!"

Guru

Join Date: Mar 2007
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Posts: 3961
#10

### Re: how to select the motor power

04/17/2012 3:21 AM

I am deeply concerned by the fact that people who are not at required level of knowledge are used for the design of equipment where human beings are involved (see spec 4 persons each 100 kg). Neither the first throw of informations nor the second gives a feeling that the designer makes more than apply a formula. I am concerned because it is not the first time we get requirements for help from people who do not understand what they are supposed to master.

I can understand that the very fast development of several economies leads to a lack of professionals but making usage of not professionals could lead to human lives loss and this is unfortunately very possible.

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#11

### Re: how to select the motor power

04/17/2012 3:46 AM

Motor power is shaft load torque mutiplied by angular velocity divided by efficiency. So, there is insufficient information in the original post to be able to answer the question.

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#12

### Re: How to Select the Motor Power

04/17/2012 6:58 AM