The long axis with CNC lathe is generally not the long axis of the car only need to have a tail top can be processed, generally processing long axis using the following three methods.
Follow the tool holder.
The purpose of using the follow tool holder is to offset the radial cutting force on the workpiece during processing, reduce cutting vibration and deformation of the workpiece with insufficient rigidity.
In the use of the follow tool holder must ensure that the center of the number bed and the center of the follow tool holder consistent, due to the characteristics of the follow tool holder is not applicable to the workpiece requiring secondary turning, only a car in place.
The hydraulic center stand can be used to make another support point at the midpoint of the chuck and tailstock in the machining, so that it is equal to the three-point support.
The middle of the workpiece is supported by the deformation caused by the rigidity problem, which ensures the accuracy of the long axis processing, and also solves the problem that the follow tool holder cannot be turned twice.
Machining by centering machine.
For the parts with high processing accuracy requirements below 32 diameter, it is recommended to use the centering machine for machining with long bar stock, which can be formed in one time, saving manpower and energy for high efficiency and high precision.
In the turning of slender shafts, in addition to solving the bending and vibration caused by the lack of rigidity of slender shafts, it should be noted that slender shafts are also prone to taper, concavity, and bamboo knot shape in the processing.
Taper is generated by the top class and the spindle center is not the axis or tool wear and so on. The solution is to adjust the accuracy of the machine tool, the use of better tool materials and the use of a reasonable geometric angle.
Concavity is the two ends of the large, small phenomenon in the middle, affecting the straightness of the workpiece. The reason for this is that the outer support claw with the tool holder is pressed too tightly, in close proximity to the back of the top class or turning head, because of the rigidity of the material top can not come.
Therefore, the workpiece diameter is large at both ends, while the middle of the rigidity is relatively weak, the support claw will be from the outside of the top, thereby increasing the depth of the eating tool, so the middle concave. The solution is to make the support claw not too tight or too loose.
