Hardware stamping accessories are widely used in various fields of our lives, including some electronic devices, auto parts, decorative materials, etc. The stamping parts we usually refer to generally refer to cold stamping parts.
Measurement method of hardware automotive stamping parts: The hole measurement of hardware stamping parts takes a small value according to the measurement method of the pass-and-stop gauge. When measuring and recording with a caliper, the small value can generally be recorded (excluding small values, such as measurement errors) Errors caused), (except for special circumstances), recording the maximum value and the average value has no practical significance. The size difference in the measurement of the aperture in all directions should be recorded in the roundness of the geometric tolerance, not the aperture.
In addition, if it is surveying and there are no dimensions for reference, it should be determined according to the condition of the cross-section. The average value cannot be simply taken. For example, the small value measured may be caused by wear somewhere on the punch. At this time, the cross-section The light band is extremely small, so this small value is meaningless.
Generally speaking, punch wear causes the punching hole to become smaller (special-shaped holes require specific analysis), so you can take the larger value when surveying and mapping. Don't forget the cross-section quality, because when making the punch, you take the basic size of the hole diameter + The maximum value within the allowable deviation is multiplied by 0.5~0.75 to leave the wear amount. After a period of use, the punching hole becomes smaller, but as long as the cross-section quality is passable, the value is still within the tolerance range. At this time, the maximum value is Correct (Similarly, factors such as deformation in the thickness direction of the plate such as hole warping should be excluded if the value is too large, especially for thin plates).