Page 31 - 《橡塑技术与装备》英文版2025年12月

MACHINERY AND MOLD

The semi-finishing process of operation 6 is completed 5 Semi-finished rough castings after
on a general-purpose lathe, mainly to remove the black oxide fine machining
layer after tempering. The two end faces are machined to a size The blank after semi-finishing turning is shown in Figure
of 4000 mm, with accurate machining allowance reserved for 4, with the flat end face dimensions in place. The two ends
finishing. The process holes for blocking plates on both ends of the blank are provided with blocking plate holes and M48
and M48 lifting holes are machined. lifting holes. Since we use Sandvik CNMG120408-PR 4425,
Here we focus on explaining the advantages of process which is a 12HP high-pressure internal cooling tool, a single-
6 on the general-purpose lathe. Although turning and sided cutting depth of 3 mm is required to ensure good chip
milling possess relatively strong processing capabilities, in breaking capability. Therefore, in process 6, a single-sided
practical applications, it is still necessary to comprehensively allowance of 3 mm is ensured, mainly considering the tool
consider the requirements of the product to avoid excessive used to ensure good chip breaking.
concentration of processes.
(1) Machine tool
Taking a medium-sized rotor shaft as an example, with
a length of 3.5 meters and a diameter of 350, after tempering,
the middle section of the shaft may exhibit bending, with the
maximum bending reaching 3~5 mm. The turning and milling Figure 4 Semi-finished product after semi-finishing
process utilizes a 24" hydraulic three-jaw chuck, which cannot turning
be adjusted. On the other hand, the 4-jaw chuck used on the
general-purpose lathe is easier to adjust. 6 Positioning and installation
A brief introduction is given to the components required
(2) Production cost
Performing semi-finishing machining on the general- for positioning and installation, such as the chuck, center
purpose machine to remove the black layer after tempering is frame, and center point, as shown in Figure 5.
more beneficial for machining on the turn-milling compound 6.1 Soft gripper
Soft jaws can maximize the repeatability of workpiece
machine, reducing machine and tool wear; some non-critical
dimensions can be machined here to reduce operations on positioning accuracy, ensuring that the centerline of the
the turn-milling compound machine and avoid excessive machined workpiece can fully coincide with the centerline
of the spindle. Most importantly, the software can achieve
concentration of work steps.
(3) Drilling deep holes after semi-finishing is better than maximum fit with the surface of the workpiece, which not
drilling deep holes after finishing, as it avoids scratching the only ensures the transmission of greater torque but also avoids
surface of the part during the transfer process. damage to the workpiece during clamping. Soft jaws are used
(4) Process 9 can be processed on a floor boring machine, for axle parts with high machining requirements, while hard
but the efficiency will be lower. This is a matter of capacity jaws are used for rotor body parts in milling.
balancing. 6.2 Setting parameters
Table 1 Process Design Taking a 5-ton part as an example, it involves a clamping
Process Process Content Process Resources force of 3 MPa from the 24 hydraulic chuck, a clamping force
1 forging open die forging of 2 MPa from the center frame, and a thrust force of 5 MPa
2 normalizing trolley furnace, 380 degrees
3 rough turning Ordinary car from the center. The maximum thrust force of this machine is
4 quenching and tempering pit furnace, 840 degrees, HB220~250. 7 MPa, and when processing a part weighing approximately 7
5 ultrasonic flaw detection ultrasonic flaw detector
6 semi-finishing lathe ordinary car tons, it corresponds to approximately 1 MPa=1 ton.
7 deep hole drilling drilling machine
8 finish turning turn-milling 6.3 Installation of blocking plate
9 drilling floor boring Install the process blind plate on the right end of the rotor

Vol.51 51 卷 ·25·
年，2025
·25·
2025 第