Mechanical Engineering - Production Engineering - Discussion
Discussion Forum : Production Engineering - Section 4 (Q.No. 12)
12.
The ratio between two consecutive spindle speeds for a six-speed drilling machine using drills of diameter 6.25 to 25 mm size and at a cutting velocity of 18 m/min is
Discussion:
12 comments Page 1 of 2.
Vishwas Patel said:
9 years ago
If n = no of spindle speeds.
The ratio between two consecutive spindle speeds is:
R = (Max rpm/min rpm)^1/(n-1).
Max rpm = (1000 * Cutting velocity)/Min diameter.
= (1000 * 18)/3.14 * 6. 25.
= 917.197.
Min rpm = (1000 * Cutting velocity)/Max diameter.
= (1000 * 18)/3.14 * 25 = 229.299.
Now ratio R = (917.197/229.299)^1/5.
= 1.32.
The ratio between two consecutive spindle speeds is:
R = (Max rpm/min rpm)^1/(n-1).
Max rpm = (1000 * Cutting velocity)/Min diameter.
= (1000 * 18)/3.14 * 6. 25.
= 917.197.
Min rpm = (1000 * Cutting velocity)/Max diameter.
= (1000 * 18)/3.14 * 25 = 229.299.
Now ratio R = (917.197/229.299)^1/5.
= 1.32.
Shravan said:
2 years ago
Cutting velocity= πDN ,
Where D=Diameter, N=speed of drill in r.p.m,
N1/N2=D2/D1=25/6.25=4.
The Ratio of spindle speeds =(4)1/6-1=(4)0.2. = 1.32Ans.
Where D=Diameter, N=speed of drill in r.p.m,
N1/N2=D2/D1=25/6.25=4.
The Ratio of spindle speeds =(4)1/6-1=(4)0.2. = 1.32Ans.
(3)
Jadeja said:
6 years ago
V=π*D*N/1000.
So, N1D1=N2D2.
N1/N2=D1/D2.
=25/6.25.
=4.
NOW,
(Nmax/Nmin)^1/(6-1).
=4^(1/5),
=1.319,
~1.32.
So, N1D1=N2D2.
N1/N2=D1/D2.
=25/6.25.
=4.
NOW,
(Nmax/Nmin)^1/(6-1).
=4^(1/5),
=1.319,
~1.32.
(1)
Bhawani Singh said:
6 years ago
@Pravin.
Because, v= πDN/1000.
There is an inverse relationship between N and D.
Because, v= πDN/1000.
There is an inverse relationship between N and D.
Samarth nawale said:
3 years ago
If 1000*18 and 3.14 is common then why uh putting values,
Simply do,
(25/6.25)^1/n-1.
Simply do,
(25/6.25)^1/n-1.
Ravki said:
7 years ago
(max speed/min speed)^( 1/ (no of speeds-1) ) = (25/6.25)^(1/5) = 1.319.
Mir said:
3 years ago
The speed ration = (Nmax/Nmin)^(1/n-1) = (Dmax/Dmin)^(1/n-1).
Pravin said:
8 years ago
@Vishwas.
Why are you taken min/ max dia= 3. 14* 6.25/25?
Why are you taken min/ max dia= 3. 14* 6.25/25?
Parth said:
8 years ago
@Pravin.
Because it's the formula for conversation.
Because it's the formula for conversation.
(1)
Akash said:
8 years ago
n(max) = (v x 1000)/(3.14 x min dia).
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