Foamed PP pepper balls are mainly used on some liquid level meters. The surface of the liquid level meter needs high buoyancy PP pepper balls. Although PP pepper balls can also float on water, the buoyancy of PP pepper balls is very small, and there is a phenomenon of ultra-micro stagnation, so PP pepper balls will not float in the liquid, which will affect the sensitivity of the liquid level meter. Therefore, the plastic balls used on the liquid level meter are hollow plastic balls except foamed pepper balls.

The manufacturing process of foamed pepper balls is relatively simple, that is, a certain proportion of foaming agent is added to the raw materials for producing pepper balls, and the foaming agent reacts chemically at high temperature in the barrel of an injection molding machine to generate gas, and the gas is fully mixed with plastic materials under the action of screw stirring and injected into the plastic ball mold, and after cooling and curing, it is foamed plastic pepper balls. The post-processing process of foamed plastic pepper balls is similar to that of solid plastic balls, and a special ball grinder for plastic pepper balls is also needed for grinding and polishing.