To avoid this kind of situation, in the production process, we should first check whether the length of the spring is standard. The difference is a thousand miles away. The effect of the length on the piston cannot be ignored. If it is short, the return stroke of the piston will not be in place. Directly cause the rebound after pressing the head down.

　　Secondly, check whether the thickness of the piston fits the body. During the movement of the piston, any gaps will cause the suction force to be weak, and the body cannot be discharged by pressing the head. Due to the thermal expansion and contraction of plastics, a normal piston is very important to ensure the quality of the lotion pump head.

　　Finally, let’s analyze the body. Given the plastic’s scalability characteristics, if the injection is not performed properly during injection molding, the insufficient injection will cut off a thin layer of the body, resulting in uneven inner walls, and inevitably leaving behind during the piston stamping process. The gap makes it impossible to discharge the material.