Great job noise. Cold stamping belongs impact work, once for each punch, make a noise issue. Punching workshop is one of the hardest hit noise nuisance. 7, punching speed, pressure, prone to injury. Due to the long mold manufacturing cycle and high manufacturing cost, when the small number of parts, cold stamping process is not economical. Only when mass production, mold manufacturing costs on the cost of the work is very small, cold stamping process became economical and reliable processing methods. Type core punchings core lamination according to different shapes, punching into a circular core punching, fan-shaped punching and poles (spade) punching. In the small AC motors and DC armature iron core are usually circular punching. DC motors and synchronous motors pole core common pole lamination press fit together. Punching core of technical requirements, the size of the bad design to meet the requirements. There are a variety of sizes on core salt tablets, but can be attributed to the internal dimension and with the size of two kinds. Internal dimensions as groove dimensions, vents, and other markers of various aperture and grooves on the pole punching, the general accuracy class H10, higher precision is unnecessary. Because the installation error groove wall and the wall of the hole caused by the irregular punching is much larger than the error itself. To fit with the size dimensions, such as the outer core, inner core circle and the shaft hole or the like with the other parts, the precision level and the process used about. 2, form and position deviation should meet the design requirements. Coaxial with the outer circle shall not exceed the difference between the stator lamination. When scheduled for punching and outside the circle for the first time while punching, its concentricity take 0.04-0.06mm, when it is due to internal and external punched twice, it may be appropriate to relax the concentricity. 3, alveolar to be evenly distributed. Groove indexing to be accurate, the difference between the maximum and the minimum width of the teeth should meet the design requirements. Otherwise, it will lead to an imbalance of the magnetic circuit. 4, punching uniform thickness, almost the entire surface, and punch small burr on the cutting. Burr on small motor stator punching sheet should not exceed 0.05mm. Cast aluminum rotor punching burr should not dry 0.1mm. 5, the insulating layer on the surface should be thin and uniform punching, good dielectric strength, oil and moisture resistant.