When you look inside a modern rotary rinser-filler-capper, the bottles seem to float from one star wheel to the next. That smooth movement is not an accident. It depends on how the machine grips and transfers each bottle. There are two broad philosophies: holding the bottle by the neck or supporting it from the base and body. The choice affects changeover time, bottle stability and the range of containers a line can run.
What Is Neck Handling?
PET bottles have a support ring, sometimes called the neck ring, just below the thread. In a neck-handling system, star wheels and grippers hold the bottle by this ring throughout the machine. The bottle body hangs freely. Air conveyors use the same principle to move empty bottles quickly from the blow moulder.
What Is Base Handling?
In a base-handling machine, bottles stand on a platform or conveyor and are guided by the body using star wheels with pockets shaped to the bottle. Glass bottles, jars and containers without a suitable neck ring generally need this approach.
Advantages of Neck Handling for PET
- Faster changeovers: if your bottles share the same neck size, you can change the bottle height or body shape without changing star wheels.
- Better stability at high speed: lightweight PET bottles are less likely to tip because they are held firmly at the top.
- Gentler rinsing: the bottle can be inverted easily for rinsing while held by the neck.
- Fewer change parts to store and maintain.
For a water plant running 500 ml, 1 litre and 2 litre bottles with the same neck finish, neck handling can reduce changeover time from an hour or more to just a few minutes.
Where Base Handling Still Makes Sense
Glass bottles are heavier and often lack a neck ring suitable for gripping, so they need support from below. Wide-mouth jars and containers with handles also suit base handling. Lines that run a mix of glass and PET may use base handling throughout for consistency.
Rinsing Considerations
In a gripper rinser, each bottle is gripped, turned upside down, sprayed with rinse water or ionised air, drained and turned upright again. With neck handling, the gripper holds the neck ring and the motion is smooth and fast. With base handling, the gripper usually clamps the bottle body, so the gripper pads must suit each bottle diameter.
Impact on Filling Accuracy
Level filling depends on the bottle being at the correct height under the valve. Neck handling references the bottle from the neck, so the distance between the valve and the bottle mouth stays the same even if bottle heights vary slightly. That can improve fill level consistency, especially with lightweight bottles.
Thinking About Lightweighting
PET bottle weights keep dropping as brands save material. Lighter bottles have thinner walls that dent easily when gripped by the body. Neck handling avoids squeezing the body at all, which is one more reason it suits lightweight PET.
Choosing for Your Plant
Consider your current and future container mix. If most of your range is PET with a common neck finish, neck handling offers clear benefits in speed and flexibility. If you run glass, jars or a wide mix of shapes, base handling may be more practical. Some machines combine both, using neck handling for PET and base support where needed.
Hilden builds rinsing, filling and capping monoblocks in both configurations. Share your bottle drawings and planned SKUs with the team, and you will get a recommendation based on how your range is likely to grow.