The pattern of EDM Texture Standard 5A represents how the pattern corresponds to EDM position 33, which represents the electrical discharge machining (EDM) position at 60 VDI. The pattern refers to the EDM (Electrical Discharge Machining) texture, where the EDM texture pattern surface is relatively uniform and resistant to scratching. Its drawback is that it results in larger product dimensions, and the EDM texture processing for mold forming may not be achieved, making it suitable for smaller-sized products.
EDM textures typically fall between VDI18 and VDI33, and their roughness and requirements are as follows:
VDI18: Corresponding to a roughness Ra0.8. In actual production, the range is Ra0.6 to Ra1.0, with a mold forming requirement of a 2.5-degree draft angle.
VDI21: Corresponding to a roughness Ra1.1. In actual production, the range is Ra0.9 to Ra1.3, with a mold forming requirement of a 3-degree draft angle.
VDI24: Corresponding to a roughness Ra1.6. In actual production, the range is Ra1.4 to Ra1.8, with a mold forming requirement of a 3.5-degree draft angle.
VDI27: Corresponding to a roughness Ra2.2. In actual production, the range is Ra2.0 to Ra2.4, with a mold forming requirement of a 4.0-degree draft angle.
VDI30: Corresponding to a roughness Ra3.2. In actual production, the range is Ra2.8 to Ra3.6, with a mold forming requirement of a 4.5-degree draft angle.
VDI33: Corresponding to a roughness Ra4.5. In actual production, the range is Ra4.0 to Ra5.0, with a mold forming requirement of a 5.5-degree draft angle.
So, these VDI standards indicate the roughness of the EDM texture and the required draft angle for mold-formed products at different EDM positions.