1, in the three-jaw chuck on the positioning parts, guiding parts and tooling parts of the manufacturing error and in use to the amount of wear will change the machine tool, tool and workpiece correct positional relationship between each other, can cause machining deviation.
2, the size of these machining deviations can also be calculated in accordance with the manufacturing tolerances of the key components of the fixture to determine. For a set of current fixtures or a set of fixtures have been used and worn fixtures, you can also measure its actual deviation. According to the results of the measurement, usually three-jaw chuck centering error of up to 0.1 ~ 0.15mm.
3, from the three-jaw self-centering chuck structure analysis, it is basically all of each part of the clearance fit. Between each part, there is a certain gap. For example, the jaws of the I-groove and three-jaw chuck shell sliding back and forth, resulting in a certain gap; flat threaded set in the shell of the mandrel, to be rotated, there is a gap; three-jaw chuck locking in the flange also has a radial amount of runout. These errors together to form a cumulative deviation, concentrated in the 3 pieces of radial runout. With the increase in wear and tear, the position of the gap also increased significantly, which is the cause of the centering error becomes larger.
Post time: Feb-13-2025