Labatory 2
BSc Industrial Engineering and Management
Production Techniques
By:
Ruben van Veen [S5733774]
2nd of March 2025
Contents
1 Introduction
1
2 Theory
1
3 Results
3.1 First Workpiece . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Second Workpiece . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Third Workpiece . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2
2
3
3
4 Conclusion
4
5 Recommendations
4
A Final tables
5
1
Introduction
At the beginning of the lab, all participants had to wear safety glasses. Then the whole
group went into a room with various mechanical devices, including a milling machine
and a turning machine. Both devices were extensively introduced as were their setup
pieces. The purpose of the laboratory is to present how the machines work and for the
students to see the machines in person. In addition, the laboratory allows students to
determine various parameters, calculate certain variables and make connections between
temperature, tool life and parameters such as cutting speed and workpiece material.
2
Theory
For the turning part of the material, the machine consists of a digital readout, a clamping
device, a toolpost and mutiple handwheels. In order to start operating the machine, the
rotational frequency [rev/min] of the machine has to be calculated:
n = (VC ∗ 1000)/(D ∗ pi)
(1)
However therefore, the cutting speed has to be defined using the table in the manual [2].
The calculation of the rotational frequency is approximately equal to 1145 [rpm], however
since the machine has several fixed setting to choose from, a frequency of 1220 [rpm] has
been used as input (it is the closets value). Last setting used is the feed. The value of
feed can be found in the manual:
f = 0.25[mm/rev]
For the milling part the same formulas have been used, but another formula is introduced.
This formula calculates the speed in the direction of the feed:
Vf = f ∗ n ∗ (number of cutting edges)
1
(2)
Now that the formula of the speed in direction of the feed has been presented, the next
variable can be calculated. In order to calculate the MRR of each operation the machining
time has to be calculated. This is done using the following formula:
Machining time = Length/(f ∗ n)
(3)
However since in the matrix machining time has to be calculated in seconds this value
will be multiplied by 60. The machining time can then be used in order to set up the
formula to calculate the material removal rate (MRR):
M RR = P I ∗ DAV G ∗ depth ∗ f ∗ n
(4)
In this formula depth of the cut has been used as well. The depth of the cut also takes
into account the number of steps used to do the roughing:
depth of cut = (D0 − DF )/(2 ∗ number of steps)
(5)
The specific energy of a operation can be found in appendix 1 in the manual [2]. Using
the specific energy, the power of the operation can be determined:
P = M RR ∗ U/60
(6)
In the formula the product of specific energy and MRR have been divided by 60, since
the specific energy is measured per minute. Dividing the total product by 60 ensures that
the Power has the right units [W]. The last variable to calculate is the cutting force:
FC = P/(VC /60)
3
Results
3.1
First Workpiece
(7)
There are multiple resulting workpieces. In the turning machine the resulting workpiece
is a cylindrical workpiece which can be screwed into a hole. All of the the angles have
been rounded of and there are multiple levels in the workpiece. This workpiece has been
roughed multiple times with different lengths and diameters. That is how those different
sizes at certain lengths were created. The parameters of the video have been used. Only
the parameter of VC has been determined using table 2 in the manual [2]. After VC ,
D and f have been filled in, n has been calculated in table 2. Important to note, is
that in the video there was no clear information given about the maximum of rotational
frequency, therefore no constraints have been added in the calculations. From step 11,
the speed has been lowered for rounding of the angles, since this has been mentioned in
the video. Important steps during the turning was changing the readout according to the
new diameters. Therefore, all diameters fell in the range. During the operation the color
was changing, because the heat that was generated went into the chips which is not a
good sign. Therefore at step 7 cutting oil was added in order to meet the surface tolerance
of Ra 6.3 and the dimensional tolerances. Another step was to change the feed to 0.05,
this also helps in meeting all requirements. During operating the machine did not make
a lot of noise or smell. At the last operations the speed has been changed to 40 [rev/min]
to prevent the tool from breaking. After operating the MRR has been calculated of
2
each operation using equation (4). Following the website of the brand Weiler Conder the
maximum power of this machine corresponds to 3kW [1]. Assuming 80 percent efficiency
means the specific energy should be multiplied by 1.25:
U ∗ 1.25 = 1.6 ∗ 1.25 = 2
(8)
Now the question is how large would the maximum MRR be, or in other words how big
is MRR if Power is equal to 3000 Watt. Rewriting the original power equation gives:
M RRM AX = (P owerM AX ∗ 60)/2 = 90000[mm3 /s]
3.2
(9)
Second Workpiece
The second workpiece has been made using the milling machine. This machine is from
the brand Schaublin 53N and has a maximum power of 3000 Watts. This workpiece
is a rectangular block with an inlet in the middle. In the cut there are several layers
whose depth has 8.05 mm and a width of 14.05 mm. The workpiece is made of Fe360
steel. The given parameters were also used for the calculations of this workpiece. The
instruction stated that VC equals 192 [m/min] and the feed equals 0.06 [rev/min]. In order
to prepare the workpiece all edges have been filed in order to make sure the workpiece
will be clamped flat on it’s surface. After this step the workpiece will be aligned with
its axes using a probe. This will produce a beeping sound when touching the workpiece,
using this will determine where the workpiece has to be clamped on the machine. For
the operations a solid carbide of 12 mm with 4 cutting teeth has been used. Then some
repetitive steps have been taken. The workpiece will first be roughed in the middle after
which the mill will be moved en the roughing starts again. This step has been done for
multiple depths and widths using conventional milling. During milling the chips that are
produced are changing color, due to heat generated by cutting material. For milling this
is a good sign since the heat is getting into the chips and not in the workpiece. In table
3 all of the parameters using the equations in section Theory. If efficiency is 80 percent,
the maximum MRR is equal to:
M RRM AX = P owerM AX ∗ 60/1.6 = 9000[mm3 /s]
(10)
Since the operations have been done using quite an old tool, the maximum frequency
is 1510 [rev/min]. However, this setting still creates a lot of noise and vibrations the
maximum frequency used is 1210 [rev/min].
3.3
Third Workpiece
The third workpiece is an aluminum made rectangular block which has been made to
to fit in the gap of the second workpiece. For this the same machine as the second
workpiece has been used. The process start with setting all axes to zero and place the
workpiece in the right position [1]. Then, the rough milling starts, which happens at a
lower speed since aluminum alloys are less robust than steel alloys. After milling all steps
have been measured using a caliper. This process repeats itself multiple times. Since the
same rotational frequency has been used an the feed is also known, the speed has been
calculated based on these values. The depth of the cut is based on the differences in
the Z-values of the cuts. Using all these values the MRR has been calculated as well as
both the power and the cutting force. Important to note that the specific energy of an
3
aluminum differs from the steel alloy. The specific energy of an aluminum alloy is equal
to 0.7 [Nm/mm3 ] Using all these values the maximum MRR could also be determined:
M RRM AX = P owerM AX ∗ 60/0.7 = 257.142[mm3 /s]
(11)
This value is much higher than the one from the steel alloy. This is the result from
the difference in specific energy since both the maximum power stays the same. The
tool life is in a better situation since the same frequency in direction has been used.
This frequency is the perfect rotational frequency in which it does provide power to the
operations, but there are few noise and vibration problems. The color of the alloy also
changes a bit, which is a good sign since a changing color indicates that the temperature
goes into the chip and not into the material.
4
Conclusion
The laboratory has showed the different operations in machining processes, including
milling and turning operations. Important here was setting parameters both before and
after operation, taking into account the quality of both the machine and the workpiece.
The laboratory showed that there is still plenty of room to improve both efficiency and
the quality of operations. Overall, the results were positive, with calculated values for
MRR, power and cutting force, which in turn fit well with theoretical expectations. The
adjustments made to the cutting speeds and the feed rates positively affected the surface
finish. However, cutting oil was often required to keep the process temperature from
rising too high. Other adjustments had to be made to the process as well, since the
machines were already quite aged. First of all, the maximum frequency had to be taken
into account when milling. However, to preserve the machine, the rpm had to be lowered
even more so that it would cause less noise and vibration nuisance. As a result, the
rotational frequency went from 5092 rpm to 1220 rpm. This makes the process go a lot
slower than calculated.
5
Recommendations
I personally did enjoy this laboratory, however there are some improvement points that
I would recommend implementing next year. First of all, the formulas are unclear which
one to use, since there are many different versions of how to calculate a certain variable.
Second of all, the laboratory should be made more interactive in which students can help
with the machining process instead of looking at how the machines work for a long time.
4
A
Final tables
# Operation
Tool
Vc D
n
f
d
t
MRR
P
Fc
1 Surfacing 1st side
HSS planed tool 30 25
381.97 0.2 0.12
74.61 529.63
14.12 28.25
2 Roughing D=22.3 l=59.9 Carbide CPGT
90 22.3
1284.66 0.25 0.45
11.19 8349.72 222.66 148.44
3 Roughing D=20.4 l=44.9 Carbide CPGT
90 20.4
1404.31 0.25 0.475 7.67
9634.47 256.92 171.28
4 Roughing D=17.4 l=34.9 Carbide CPGT
90 17.4
1646.43 0.25 0.5
5.09
11890.09 317.07 211.38
5 Roughing D=12 l=19.9 Carbide CPGT
90 12
2387.32 0.25 0.54
2.00
18619.88 496.53 331.02
6 Finishing D=22.15 l=60 Carbide CPGT
50 22.15 718.53 0.05 1.305 100.20 2708.69 72.23 86.68
7 Finishing D=20 l=45
Carbide CPGT
50 20
795.77 0.05 1.075 67.86 2471.16 65.90 79.08
8 Finishing D=16.975 l=35 Carbide CPGT
50 16.975 937.58 0.05 1.5125 44.80 4096.45 109.24 131.09
9 Finishing D=11.8 l=20
Carbide CPGT
50 11.8
1348.77 0.05 2.5875 17.79 10081.38 268.84 322.60
10 Tapered side for Thread HSS planed tool 50 11.78 1351.06 0.05 0.01
17.76 39.03
1.04
1.25
11 Rounding-off angles
HSS planed tool 40 11.775 1081.31 0.05 0.0025 22.20 7.81
0.21
0.31
12 Threading M12 l=15
HSS + cutting oil 40 11.775 1081.31 0.05 0
13.32 0
0
0
Table 1: Turning Operations
# Operation
Tool
Vc D n
f
d t
MRR P
Fc
1 Deburr
file
2 Set X and Y axes to zero
3 Set Z axis to zero
HSS cutter 12 mm
4 X axis in position for workpiece
HSS cutter 12 mm
5 Y axis in position 0 and Z -3.8
HSS cutter 12 mm
6 Rough mill gap Z= - 3.8 and Y=0 HSS cutter 12 mm 192 12 1220 0.06 1.9 10.2459 1668.96 44.5056 13.908
7 Set Y+3.8
HSS cutter 12 mm
8 Rough mill gap Z=-3.8 and Y=+3.8 HSS cutter 12 mm 192 12 1220 0.06 3.8 10.2459 3337.92 89.0112 27.816
9 Set Y=-3.8
HSS cutter 12 mm
10 Rough mill gap Z=-3.8 and Y=-3.8 HSS cutter 12 mm 192 12 1220 0.06 3.8 10.2459 3337.92 89.0112 27.816
11 Measure: width 20.05, depth 4.05
caliper
12 Finish Z=-4 and Y=+4
HSS cutter 12 mm 192 12 1220 0.06 0.2 40.98361 175.68 4.6848 1.464
13 Finish Z=-4 and Y=-4
HSS cutter 12 mm 192 12 1220 0.06 0.2 40.98361 175.68 4.6848 1.464
14 Rough mill Z=-7.8 and Y=0
HSS cutter 12 mm 192 12 1220 0.06 3.8 40.98361 3337.92 89.0112 27.816
15 Rough mill Z=-7.8 and Y=0.8
HSS cutter 12 mm 192 12 1220 0.06 3.8 40.98361 3337.92 89.0112 27.816
16 Rough mill Z=-7.8 and Y=-0.8
HSS cutter 12 mm 192 12 1220 0.06 3.8 40.98361 3337.92 89.0112 27.816
17 Measure
caliper
18 Finish Z=-8 and Y=1
HSS cutter 12 mm 192 12 1220 0.06 0.2 40.98361 175.68 4.6848 1.464
19 Finish Z=-8 and Y=-1
HSS cutter 12 mm 192 12 1220 0.06 0.2 40.98361 175.68 4.6848 1.464
20 Measure: width 14.05 depth 8.05
caliper
Table 2: Milling Operations part 1
5
# Operation
Tool
Vc
Dn
f d t
MRR P
Fc
1 Deburr
file
2 Set X and Y axes to zero
3 Set Z axis to zero
HSS cutter 16 mm
4 X axis in position for Workpiece
HSS cutter 16 mm
5 Y axis in position +15.2 and Z=-3.8 HSS cutter 16 mm
6 Rough mill Y+15.2 and Z=-3.8
HSS cutter 16 mm 61.32389 16 1220 0.2 3.8 4.098361 11126.4 129.808 127.0056
7 Y axis in position -15.2 and Z=-3.8 HSS cutter 16 mm
8 Rough mill Y=-15.2 and Z=-3.8
HSS cutter 16 mm 61.32389 16 1220 0.2 3.8 x
11126.4 129.808 127.0056
9 Measure: width and depth
HSS cutter 16 mm
10 Finish Y=-15 and Z=-4
HSS cutter 16 mm 61.32389 16 1220 0.2 0.2 4.098361 585.6
6.832
6.68
11 Finish Y=+15 and Z=-4
HSS cutter 16 mm 61.32389 16 1220 0.2 0.2 4.098361 585.6
6.832
6.68
12 Measure
caliper
13 Rough mill Y=-18.2 and Z=-7.8
HSS cutter 16 mm 61.32389 16 1220 3.8 3.8 0.215703 211401.6 2466.532 2413.107
14 Rough mill Y=+18.2 and Z=-7.8
HSS cutter 16 mm 61.32389 16 1220 3.8 3.8 0.215703 211401.6 2466.532 2413.107
15 Measure: width and depth
caliper
16 Finish Y=-18 and Z=-8
HSS cutter 16 mm 61.32389 16 1220 0.2 3.8 4.098361 11126.4 129.808 127.0056
17 Finish Y=+18 and Z=-8
HSS cutter 16 mm 61.32389 16 1220 0.2 3.8 4.098361 11126.4 129.808 127.0056
18 Measure: width and depth
caliper
Table 3: Milling Operations part 2
6