×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

calculation cutting force to power and torque at the cutting tool_I don't understand it ??????

calculation cutting force to power and torque at the cutting tool_I don't understand it ??????

calculation cutting force to power and torque at the cutting tool_I don't understand it ??????

(OP)
I encountered a strange calculation problem that I can not explain:

I calculate the power torque of a disc milling cutter.

cutter diameter Dc= 63mm
quantity cutting teeth Z= 5
cutting speed vc= 140 m/min
feed fz=0,1 mm
specific cuttingforce for the material Kc1= 2000 N/mm^2
exponent value for specific cuttingforce change mc=0.25
depth of cut ae= 3,4 mm
width of cut ap= 8.53 mm
surface section full depth cut = 29 mm^2

This is my calculation:
average chiptickness hm=fz*SQRT(ae/Dc)= 0,1*SQRT(3,4/63) = 0,023 mm (simplified formula)
cuttingforce for this chiptickness Kc=kc1*(1/hm^mc) = 2000*(1/0,023^0,25)=5135 N/mm^2
cuttingforce Fc=surface cut x kc = 29 mm^2 x 5135 = 148915 N
Pc= Fc x vf= (148915 x 353,68)/60x10^6 = 0,8778 kW
Mc=(Pc x 30 x 10^3)/pi x n = 0,8778 x 3000/pi x 707 = 11,85 Nm

This has all been confirmed by several calculators and should be more or less correct BUT now my problem !!!!

If I calculate the moment of torque Mc out of the cutting force : Mc = Fc x Dc/2 (Nm) = 148915N x 0,0315m = 4691 Nm

????? What will be the torque that my tool will need ????

This 4691 Nm can not be correct that is far too much but still I calculate it from the same force that I use in the other forumula.
I am really confused here. Am I mixing up different forces ?



Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

Research Report - What’s the State of Nonlinear Simulation?
Simulation is an increasingly valuable tool across the product design workflow, but not all simulations are equal. We set out to determine how engineers and product designers make use of specialized analyses, how they incorporate nonlinear simulation into their work and how they rate the available software. Download Now
White Paper – Data Security and Know-How Protection
Our data is constantly exposed to the danger of being intercepted or stolen as it wends its way over global data networks. Data security measures and measures for protecting intellectual property should not, however, first be implemented when data is exchanged – companies must lay the foundation for these measures within their own organization. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close