Many factories believe bottle base deformation is caused during the final high-pressure blowing stage.

But in reality, the problem often starts much earlier.

At BANGEMACHINE, we frequently find that unstable bottle bases are actually the result of incorrect thermal preparation before blowing even begins.

Especially during high-speed PET production.

Why?

Because the bottle base is one of the most stress-sensitive areas in the entire container.

It experiences:

Stretching force

Pressure expansion

Cooling shrinkage

Vacuum load

Transportation impact

Top-load stress

If the thermal-pressure balance is not stable, the base becomes the first area to fail.

One of the most common hidden causes is uneven preform temperature distribution near the gate area.

When the gate region remains too cold while surrounding material becomes too soft, molecular orientation becomes unbalanced during stretching.

This creates:

Base rocking

Petaloid deformation

Center push-up instability

Poor vacuum resistance

Uneven crystallization control

Another overlooked factor is stretch timing synchronization.

If the stretch rod reaches the base too early before the material becomes fully pliable, the PET chains may overstress locally.

But if stretching happens too late, the base may expand without proper orientation support.

Both conditions reduce structural stability.

This is why BANGEMACHINE focuses heavily on:

Servo stretch coordination

Base cooling balance

Pressure curve optimization

Gate temperature control

Wall thickness distribution analysis

Because stable PET production is not simply about forming a bottle shape.

It is about controlling how the PET material behaves under heat, pressure, and mechanical force during every millisecond of the cycle.

In lightweight bottle production, this becomes even more critical.

Reducing resin weight without controlling base stability often creates long-term production risks:

Bottle collapse

Transport deformation

Filling instability

Higher burst rate

Poor stacking performance

At BANGEMACHINE, we believe lightweighting should never sacrifice structural reliability.

A lightweight bottle must still remain production-stable.