Accuracy requirements for injection molds of rural lighting ready boards in Africa

For outdoor working conditions in rural Africa, it is recommended to control the machining accuracy of key dimensions of the injection molding shell mold cavity for lighting Ready Board Box within ± 0.02-0.03mm, and control non critical external dimensions within ± 0.04-0.06mm. Refer to GB/T 14486-2008 and select MT4 precision level to ensure consistency in batch box size and meet the requirements of door assembly, EPDM rubber strip sealing, and terminal installation.

The surface roughness Ra of the mold cavity is ≤ 0.8 μ m, the misalignment control of the parting surface is ≤ 0.02mm, and the clearance between the slider and the insert is 0.01-0.02mm to avoid burrs and batch size drift. The sealing strip groove is a critical functional position, and the accuracy of the mold groove width and depth must reach ± 0.025mm, with a groove offset of no more than 0.03mm. Otherwise, it will directly change the compression rate of the sealing strip, causing IP protection failure. It is suitable for environments in Africa with frequent sandstorms and large temperature differences between day and night.

Due to the fluctuation of plastic shrinkage rate, the actual size of the finished plastic parts will be enlarged. The tolerance of the outer dimensions of the shell is controlled within ± 0.10-0.15mm, and the tolerance of the sealing groove is within ± 0.05mm, ensuring the interchangeability and assembly of multiple batches of boxes. Wear resistant cavity steel is selected for mold steel to cope with long-term mass production wear. The cavity size is rechecked every certain mold production to prevent gradual size deviation caused by wear.

Simultaneously matching balanced cooling water channels to reduce shell warping and deformation, relying solely on mold mechanical accuracy is not sufficient to ensure consistency; Continuous testing of 50 molds, with critical dimensions CPK ≥ 1.33, to confirm the stability of the process window and achieve uniform size of large quantities of boxes, ensuring interchangeability and protection reliability during on-site installation.