What problems should be paid attention to when making plastic bottles?
(1) When designing a squeeze plastic bottle, if the material is high-density polyethylene or polypropylene, the cross-section of the plastic bottle should be rectangular or oval. For low-density polyethylene or other flexible plastic bottles, its cross-section should be The cross section is preferably circular. This facilitates the extrusion of the contents from the plastic bottle. The plastic parts used in conjunction with the plastic bottle mouth are mainly bottle caps and sealers. The design of the plastic bottle mouth should focus on how to make the plastic bottle mouth better fit with the cap and sealer. The bottom of the plastic bottle is the weak part of the mechanical properties of the plastic bottle. Therefore, the bottom of the plastic bottle is generally designed to be inwardly concave; the corners of the plastic bottle and the inner recess are made of larger arcs. In order to facilitate the stacking of plastic bottles and increase the stacking stability of plastic bottles, an inner groove should be designed at the bottom of the plastic bottle.
(2) When labels are used on the surface of plastic bottles, the label surface should be flat. A "frame" can be designed on the surface of the plastic bottle, so that the label can be positioned accurately without movement. In blow molding, the part that the parison blows first touches always tends to be the part that hardens first. Therefore, the wall thickness of this part is also larger. The edge and corner parts are the parts where the parison is inflated and finally contacted, and the wall thickness of this part is relatively small. Therefore, the edges and corners of plastic bottles should be designed with rounded corners. Changing the surface shape of the plastic bottle, for example, the middle of the plastic bottle is relatively thinner, and adding circumferential grooves or ribs on the surface of the plastic bottle can improve the rigidity and bending resistance of the plastic bottle. Longitudinal grooves or stiffeners can eliminate deflection, sagging or deformation of plastic bottles under long-term loads.