Why are there some bumps on the lid of the plastic cup?

Our company develops and produces various stainless steel water cups. The lids are available in plastic, stainless steel, and plastic and stainless steel combinations. In the process of global sales, some customers will have questions about the bumps on the plastic cup lid. Customers are worried about whether these bumps are a symbol of defective products and will affect the use of the water cup, especially the heat preservation performance of the water cup. So why are there some bumps on the lid of the plastic cup?

The bumps on the lid of the water cup are caused during the production process. The plastic cup lid uses an injection molding process. The plastic raw material particles are added to the injection molding machine, and the particles are melted at high temperature and injected into the mold. When the cup lid product is formed and falls off the mold, a bump will appear at the position of the feed inlet. This is a normal production phenomenon and will not affect the use of the cup, nor will it affect the insulation performance of the cup.

Dongguan Zhanyi Commodity Technology Co., Ltd. not only produces all kinds of stainless steel water cups, but also all kinds of plastic water cups. Our company has more than 50 injection molding machines and bottle blowing machines, and more than 10 various ultrasonic machines. Welcome global buyers to visit our website, we not only provide product OEM service, but also provide sample processing business. You can select existing models on our company website, and you can also modify designs based on existing models.