Week 9 Machining with Planer Challenge

MACHINING USING PLANER MACHINE

OBJECTIVE

To conduct explicit dynamics study for studying the effect of two different cutting velocities on the equivalent stress, total deformation and temperature.

METHODOLOGY

The material for the workpiece was steel 1006. The cutting tool was assigned as rigid. Body interaction was set to be frictionless. The objects were meshed to have 6573 nodes and 10171 elements. Two cutting velocities were 20000 mm/s and 15000 mm/s. The end time for the former cutting velocities was given 0.00075s and 0.001s respectively in order to simulate the cutting until the end of 15 mm length workpiece. Since the workpiece was stationary, all degree of freedom at the lower face of the workpiece was set to zero. The velocity was assigned to cutting tool. Finally, total deformation, equivalent stress and user-defined temperature were evaluated.

RESULTS AND DISCUSSION

The total deformation, equivalent von mises stress and temperature were evaluated. Table 1 compares the results for two different cutting velocities. The temperature and total deformation for the case 1 with 20000 mm/s is higher than the case 2 with 15000 mm/s. The total deformation for the cases of 20,000 mm/s and 15,000 mm/s are 34.312 mm and 32.834 mm respectively. The maximum von mises stress over time is higher for 20000 mm/s case (673.99 MPa) compared to 15000 mm/s (659.98 MPa). But, at the end time, von mises stress of 20,000 mm/s reduced considerably from 673.99 MPa to 439.84 MPa whereas there is no change for the 15000 mm/s cutting velocity. When the cutting velocity is increased from 15,000 mm/s to 20,000 mm/s, the temperature increased by 3.02 °C. For each case, the simulation screenshots are provided from Fig. 1 to Fig. 6.

Cutting velocity	20000 mm/s	15000 mm/s
Total deformation (End time) (mm)	34.312	32.834
Maximum total deformation (mm)	34.312	32.834
Von Mises stress (MPa)	439.84	659.98
Maximum Von Mises stress (MPa)	673.99	659.98
Temperature (°C)	367.77	364.75

CASE 1 (20000 mm/s)

Fig. 1 Total deformation in mm

Fig. 2 Von Mises stress in MPa

Fig. 3 Temperature in °C

CASE 2 (15000 mm/s)

Fig. 4 Total deformation in mm

Fig. 5 Von Mises stress in MPa

Fig. 6 Temperature in °C

CONCLUSION

Numerical analysis was conducted for investigating the total deformation, von mises stress and temperature during planning operation using a machine planer. The surface quality of the workpiece is nearly same for the cases of 20000 mm/s and 15000 mm/s cutting velocities. The maximum total deformation, maximum von mises stress over time and temperature are higher at the cutting velocity of 20,000 mm/s than at 15000 mm/s. Fine meshing was not carried out since the analysis was performed in Ansys student version.