BJY 350ml PET Blowing Mold

Burnt corners or incomplete filling on a 350 ml bottle are rarely a machine issue—they are a venting issue. When you blow PET at high speed, the air in the cavity must escape immediately. If it does not escape, it creates a back-pressure cushion. BJY solves this with “Micro-Geometry Venting” integrated into our 150*408 mm high-quality aluminum alloy modules. We machine our primary vents to the “Golden Zone” of precise depth: deep enough to effectively exhaust air, but shallow enough to prevent PET ingress and flash.

In many cheaper aluminum molds, the vents eventually collapse under blowing pressure. We prevent this by using a high-grade aluminum alloy with high yield strength. Our cavities are designed to maintain these micro-channels over years of continuous service. We strategically position venting at the parting line and the base inserts—the critical areas where air traps typically occur. This ensures that even the most complex 350 ml container shapes come out with sharp, clean details every time.

The logic is simple: better venting allows for lower blowing pressure. When the air gets out of the way effortlessly, your machine does not have to work as hard. This reduces the strain on your valves and seals, effectively extending your equipment’s service life. Our high-quality aluminum alloy modules feature high-capacity back-vents that ensure an unobstructed exhaust path, even at peak production speeds.

BJY (Foshan Baijinyi) has been refining these designs since 2011. We know that bottle crispness comes from the details you cannot see with the naked eye. Our 150*408 mm molds are built for technical operators who demand stability and quality. Do not let a simple air trap ruin your production efficiency.