Blow molds compatible with Sidel blow molding equipment

A mismatch between the bottom mold lifting timing and the pre-blowing curve causes localized material accumulation at the bottle base, forming a "mushroom bottom," which directly reduces the drop resistance and overall yield rate of PET bottles.

The core of eliminating bottom material accumulation lies in the dual constraint of the cavity's 3D curve and the kinematic accuracy of the bottom mold guide rails. Based on the biaxial stretching rheological properties of the PET material, we perform discrete modeling of the wall thickness distribution inside the cavity, strictly controlling the radial and axial stretch ratios of the bottom transition arc within a specific range. This 3D geometric constraint forces the melt to thin evenly along the mold wall during the high-pressure blowing stage, preventing non-oriented coiling of polymer chains at the corners. Simultaneously, the bottom mold lifting guide rails adopt ultra-hard grinding process, compressing the straightness error of the sliding surface to within 0.015mm/m. This ensures that the bottom mold produces no micro lateral shift the moment it completes closing under a 30-40bar upward thrust, thereby mechanically locking the physical triggers of wall thickness eccentricity and stress concentration.

Can be directly used as replacement molds for blow molding machines and filling lines of brands such as Sidel, Krones, KHS, and Tetra Pak.

In the surface treatment phase, the inner wall of the cavity undergoes a standardized wet blasting process, stabilizing the surface roughness at Ra 0.8-1.2μm and forming a uniform micro-pit texture. This specific surface morphology not only breaks the local vacuum adsorption effect during demolding to reduce friction resistance, but also provides a sufficient mechanical interlocking baseline at the micro-level for subsequent sleeve labeling or offset printing processes, effectively preventing label slippage or wrinkling. If you want to learn more about this product, please feel free to contact us for more information.