Plastic Round Food Container Mold: The Tooling Behind the Tub

A round plastic tub holds the yogurt, the soup, the dip, and the leftovers. The shape is simple: a round body, a rim, a base. The mold that makes it has to fill the cavity, cool the part, and eject it at a speed that makes the packaging cost work. A plastic round food container mold is built for the volume. Multi-cavity, hot runner, fast cycle. For the packaging converter and the food brand, the mold is the tooling behind the tub.

The Round Cavity and the Rim

The cavity is round, with the slight taper from the rim to the base. The taper lets the container release from the core. A plastic round food container mold with the proper taper produces the tub that comes out clean.

The rim is the sealing surface. The lid or the film seals to the rim. The rim has to be flat, smooth, and flash-free. A plastic round food container mold with the properly machined rim produces the tub that seals.

The base has the recess or the stacking feature. The tubs stack for the shipping and the shelf. A plastic round food container mold with the proper base geometry produces the tubs that nest.

The Fill and the Gate

The gate is where the melt enters the cavity. For the round container, the gate is usually in the center of the base. The melt flows outward from the center, filling the base and then the walls. A plastic round food container mold with the center gate fills the cavity evenly.

The hot runner keeps the melt at the right temperature up to the gate. No cold runner to trim. A plastic round food container mold with the hot runner system saves the material and the cycle time.

The gate vestige is the mark left on the tub. The small, smooth vestige is acceptable on the base. A plastic round food container mold with the properly designed gate leaves the vestige that does not affect the function.

The Cooling and the Ejection

The cooling channels run through the core and the cavity. The core is the inside shape, the hardest part to cool. A plastic round food container mold with the properly cooled core hits the cycle time.

The ejection system pushes the tub off the core. The stripper ring or the ring of the ejector pins on the rim releases the part. A plastic round food container mold with the proper ejection releases the tub without the deformation.

The surface finish matters. The inside of the tub has to be smooth for the food contact. A plastic round food container mold with the polished cavity produces the smooth tub.

Here is what a plastic round food container mold has to deliver:

• Round cavity with the proper taper
• Flat, smooth rim for the sealing
• Base geometry for the stacking
• Center gate with the hot runner
• Cooling channels in the core and the cavity
• Stripper or the pin ejection without the damage

The Yogurt and the Dip

The yogurt producer uses the tub for the single-serve and the family size. The tub seals with the foil. The dip producer uses the tub for the hummus, the salsa, and the guacamole. The deli uses the tub for the salads and the soups.

The Rim That Flashes and the Tub That Warps

The rim flashes because the clamp force was not enough or the parting line was worn. The properly maintained mold with the right clamp holds the rim flat. The tub sticks because the draft was too small. The proper taper releases the tub. The tub warps because the cooling was uneven.

A plastic round food container mold is the tooling that makes the tub. The cavity fills. The rim seals. The tub stacks. Choose a mold with the right taper, the flat rim, and the proper cooling.