Speed Calculation for Tool Life Optimization

What is the suitable speed in rpm to achieve a tool life of 30 minutes?

Given data:

• Diameter of cylindrical rod, d = 50 mm
• Length of cylindrical rod, L = 100 mm
• The tool life of a carbide tool used for turning operation is 3 hours when turning at 900 rpm
• If the cutting speed is doubled, the tool life is reduced to 1 hour

Calculate the suitable speed in rpm to achieve a tool life of 30 minutes.

Answer:

To calculate the suitable speed in rpm to achieve a tool life of 30 minutes, we can follow these steps:

Tool Life Optimization Calculation:

Given that the tool life is 3 hours when the cutting speed is 900 rpm:

3 = (π x 50 x 900) / 1000

Now, when the cutting speed is doubled and the tool life is reduced to 1 hour:

1 = (π x 50 x 1800) / 1000

Dividing the two equations, we get:

3 / 1 = ((135π / 1000) / (90π / 100))

1/2 = 135 / 900

Therefore, the suitable speed to achieve a tool life of 30 minutes is:

v = πdn / 1000

30 = (π x 50 x n) / 1000

n = (30 x 1000) / (π x 50)

n = 191 rpm (approx)

Hence, the suitable speed in rpm to achieve a tool life of 30 minutes is 191 rpm.