Why are there obvious trace lines on both sides of the plastic water cup?

Why is there a trace line on each side of the plastic water cup body?

This trace line is called the mold clamping line that we produce professionally. The molds for producing plastic water cups vary with the size of the product. However, most plastic water cup processes require that the mold processed needs to be composed of two parts. The two halves of the mold are closed. Together to form a complete set of molds, the gap between the two halves is the mold closing line. The more precisely the mold is processed, the thinner and lighter the mold closing line of the finished water cup will be. Therefore, the brightness and depth of the mold closing line are mainly caused by the craftsmanship of the mold.

Is there a way to completely eliminate the mold line? Under the premise of using the two-piece mold closing production process, it is actually impossible to truly eliminate the mold closing line. However, through excellent workmanship and exquisite production technology, the mold closing line on the finished product can be made invisible to the eye. But if you touch it after applying it, you can still feel that there are some bulges at the mold closing line.

Is there any process but there is no mold clamping line? It is possible to open a complete barrel mold so that the processed product does not have a mold closing line, but not all products are suitable for barrel molds. Therefore, it is normal to have a mold closing line on the surface of the plastic. It does not mean that a mold closing line on the surface of the water cup is a defective product. But when you buy a water cup, you can get started and feel the workmanship.

Will there be a mold fitting line for the stainless steel water cup body? This is basically not possible, because the production methods of stainless steel water cups and plastic water cups are completely different. At the same time, even if there are some raised points or lines on the surface of the stainless steel water cups, they can be corrected and smoothed through the shaping and polishing processes. However, once the plastic water cups are removed, Molding cannot solve these problems through shaping or polishing.

In addition to plastic water cups that have mold closing lines, what other materials have water cups that have mold closing lines? In this way, as long as the water cup is produced by hot-melt material and produced using two half-piece molds, there will be a mold closing line.