Scribd
Upload
342 views2 pages

Machining Time Calculation

The document provides calculations to determine the machining time for a casing wear ring. It details the material being cut (grey cast iron), cutting tool material (high speed steel), and feed rate and depth of cut values. It then calculates the machining time for various operations - turning, boring, and facing - considering factors like length and depth of cut. The total machining time is calculated to be 14.79 hours, excluding additional processes like forming, drilling, and machining allowances.

Uploaded by

windgust82
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
342 views2 pages

Machining Time Calculation

The document provides calculations to determine the machining time for a casing wear ring. It details the material being cut (grey cast iron), cutting tool material (high speed steel), and feed rate and depth of cut values. It then calculates the machining time for various operations - turning, boring, and facing - considering factors like length and depth of cut. The total machining time is calculated to be 14.79 hours, excluding additional processes like forming, drilling, and machining allowances.

Uploaded by

windgust82
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
You are on page 1/ 2

CASING WEAR RING

MACHINING TIME
MATERIAL TO BE CUT

Grey Cast iron ASTM A-35

MATERIAL OF CUTTING TOOL

High speed steel HSS

FEED RATE AND DEPTH OF CUT

The following values were obtained from Machinery handbook,

Feed rate, f = 0.012 ipr
Depth of cut = 0.125in.

CUTTING SPEED

In the machinery handbook the cutting speed for cast iron was given in two ways,
1- Cutting speed for through scale machining
2- Cutting speed for under scale machining

Note:
For casted products a hard scale is present on the surface so, while machining the value of
through scale cutting speed should be used upto a certain depth (usually 2-3 mm).

MACHINING TIME CALCULATION

The following are the processes involved in the machining of the wear ring:
Turning
Facing
Boring
Forming
Drilling

1- Turning 1
Outer radius of casted part, ro =13.5825in.
Required radius, r =12.992in.
Depth of machining =0.5905in.
No. of times depth of 0.125in. to be given=4.724 i.e. 5 times
The machining time for a depth of, 0.125in. =tm =
12
c
L D
V f

=
(4.661)( )(27.165)
(12)(70)(0.012)

=39.462min.
The time in turning upto a depth of,0.5905in. =Tm1=(39.462x5)
=3.29hr.

2- Boring 1
Outer radius of casted part, ro =10.925in.=required radius
Required radius, r =10.433in.
Depth of machining =0.492in.
No. of times depth of 0.125in. to be given=3.936 i.e. 4 times
The machining time for a depth of, 0.125in. =tm =
12
c
L D
V f

=
(4.661)( )(25.984)
(12)(70)(0.012)

=37.75min.
The time in boring upto a depth of, 0.492in. =Tm2=(37.75x4)
=2.516hr.
3- Facing 1
Length of cut, L =4.134in. =(ro ri)
Depth of machining =1.1966in.
No. of times depth of 0.125in. to be given=9.5728 i.e. 10 times
The machining time for a depth of, 0.125in. =tm =
12
c
L D
V f

=
(4.134)( )(25.984)
(12)(70)(0.012)

=33.48min.
The time in facing upto a depth of, 1.1966in. =Tm3=(33.48x10)
=5.579hr.

4- Boring 2
Length of cut, L =2.165in.
Depth of machining =1.378in.
No. of times depth of 0.125in. to be given=11.024 i.e. 12 times
The machining time for a depth of, 0.125in. =tm =
12
c
L D
V f

=
(2.165)( )(25.984)
(12)(85)(0.012)

=14.44min.
The time in boring upto a depth of, 1.378in. =Tm4=(14.44x12)
=2.88hr.

5- Turning 2
Length of cut, L=1.181in.
Outer radius of casted part, ro =12.992in.
Required radius, r =12.795in.
Depth of machining =0.197in.
No. of times depth of 0.125in. to be given=1.576 i.e. 2 times
The machining time for a depth of, 0.125in. =tm =
12
c
L D
V f

=
(1.181)( )(25.984)
(12)(85)(0.012)

=7.876min.
The time in turning upto a depth of,0.5905in. =Tm5=(7.876x2)
=0.2625hr.
This machining has to be done twice so,
Tm5=(0.2625x2)=0.525hr.
TIME OF MACHINING
TM =(Tm1+Tm2+Tm3+Tm4+Tm5)
=14.79hr
Note:
This machining time is exclusive of the time required to form radius, drilling, allowances
and is the time consumed in machining processes based on standard feed rate and depth of
cut.

You might also like