Automatic Cap Delivery for Efficient and Reliable Capping

Automatic capping machines would do little speed up the process without some manner of delivering closures to containers. For those packagers with high-speed production and large demand, placing caps on each container is simply not feasible. Cap delivery systems allow cappers to keep up with other components of automated packaging lines and truly put the automatic in automatic capping machines.

While the types of closures used for any type of packaging project may vary greatly - from screw-on and snap on caps to corks, ROPP closures and more - the cap delivery systems used for the different closures will often look very similar. Described below are the most often seen features of any cap delivery system along with a short description of the purpose of each feature.

Cap Elevator

A cap elevator will be used for a variety of different closures, offering a bulk hopper and a method of orienting caps for delivery to the capping machine. Cap elevators allow operators to dump bulk caps into a hopper at the bottom of a flighted conveyor belt. The flights on the conveyor belt will move caps to the top of belt, allowing those not oriented correctly to drop back into the hopper and ride the elevator again until properly positioned to be delivered to the chute, described below. Elevators can handle different cap sizes and shapes and the positioning, including the tilt of the elevator, allow for the proper orientation.

Vibratory Bowl

Vibratory bowls offer an alternative to cap elevators, though for some closures the two will be used in tandem. Vibratory bowls allow the operator to load bulk closures into the bowl itself. The vibration of the bowl allows caps to climb the outside of the bowl, also being delivered to a chute. Air jets positioned along the path of the caps allow improperly oriented caps to be blown back into the bowl, so that like the elevator only properly positioned caps reach the bottles or other containers. Vibratory bowls can also offer a solution for a range of different caps and sizes.


Once a cap has completed the trip up the elevator or around the vibratory bowl, it will be delivered to a chute. In the most common setup, the chute will hold a row of caps above a power conveyor, allowing bottles or containers to strip one cap as it passes by, with the bottle and cap combination then entering the capping area to be sealed. The chute for any capping machine can be adjusted easily to allow for a range of cap sizes. Many capping machines also include what is known as a full-chute pause, which is a sensor that will pause the elevator or the bowl when the chute is full, to avoid jams and backups of the cap delivery system.

Stabilizing Devices

As noted above, the chute holds caps for the bottles as they move into the capping machine. To allow for reliable capping, the chute must hold the closures in a specific position to allow bottles to properly acquire a cap. Most chutes will include a tongue and fingers to help stabilize the closure as they reach the end of the chute. Generally speaking, the fingers hold the sides of the cap while the tongue applies a top pressure to ensure proper positioning and avoid issues like cross threading or missed caps. The setup of the stabilizing devices may be modified or differ slightly depending on the type, shape and size of the closures being used for any project.

While not every automatic capping project is the same, the concept of a cap delivery system must include a method of orienting, delivery and stabilizing closures for delivery to the bottles. Each system will be hand tailored to the project at hand to ensure consistent, efficient and reliable delivery. To learn more about automatic cappers and cap delivery systems, contact Liquid Packaging Solutions today.