How to design mold clearance in precision machining design?
Publish Time: 2024-08-12
In precision machining design, the design of mold gap is a crucial link, which directly affects the dimensional accuracy, surface quality and service life of the product.
1. Basic principles for determining mold gap
Material factors: The size of the mold gap should be determined according to the type, thickness and hardness of the material being processed. Generally speaking, the thicker the material and the higher the hardness, the required mold gap should be appropriately increased.
Product requirements: The dimensional accuracy, shape complexity and surface quality requirements of the product are also important factors in determining the mold gap. For products with high precision and high quality requirements, the mold gap needs to be designed more accurately and reasonably.
Mold material: The strength and wear resistance of the mold material will also affect the design of the mold gap. Mold materials with high strength can withstand greater punching pressure, but may also require a smaller gap to avoid material extrusion deformation.
2. Specific design method of mold gap
Calculation method:
According to the dimensional tolerance of the product and the manufacturing accuracy of the mold, the size of the mold gap is determined by a calculation formula. This method requires accurate product size data and mold manufacturing capacity data.
For example, for a punching die, a reasonable mold gap range can be calculated based on the dimensional accuracy of the punching part and the wear of the mold edge.
Empirical method:
Based on industry experience and standards, refer to the mold gap design of similar products and make adjustments based on actual conditions. This method is simple and fast, but may not be accurate enough.
It is generally recommended that the total mold gap is 20% to 25% of the material plate thickness, which is a more commonly used empirical value range.
Experimental method:
The effect of different mold gaps on product quality is verified through experiments to determine the best mold gap. This method requires more time and resources, but the results are more reliable.
3. Precautions
Gap uniformity: The mold gap should be kept uniform and consistent to avoid excessive or too small local gaps to ensure the dimensional accuracy and surface quality of the product.
Mold wear: The mold will wear during use, resulting in changes in the mold gap. Therefore, when designing the mold gap, the wear of the mold should be taken into account and a certain amount of adjustment space should be reserved.
Selection of mold material: Selecting the right mold material is also an important factor in ensuring the stability of the mold gap. The mold material should have sufficient strength and wear resistance to withstand various forces and wear during stamping.
The design of mold gap in precision machining design is a process that comprehensively considers materials, product requirements and mold manufacturing capabilities. By combining calculation, experience and experiment, a reasonable mold gap can be designed to ensure the product's dimensional accuracy, surface quality and mold life. At the same time, attention should also be paid to the uniformity of the mold gap and the selection of mold materials.
