CAPPING MACHINES

In production and packaging, closing the product securely matters as much as filling it correctly. Capping machines, used to close filled bottles, jerry cans, jars, tins and similar containers in a leak-tight manner, are among the most important pieces of equipment on a production line. A correctly selected capping machine helps increase production capacity while reducing capping errors, product losses and labour requirements.

Capping systems used in sectors such as food, beverages, cosmetics, chemicals, cleaning products, mineral oils, agricultural products and pharmaceuticals can be designed specifically for the container format, the cap type and the production speed. From manual applications to fully automatic production lines, these machines place caps on the container in the correct position and close them at the specified tightening force.

Capping machines developed by Arsanmak are engineered to suit different cap and container types. The appropriate capping solution for the plant can be determined by assessing line capacity, cap type, container dimensions and product characteristics.

What Is a Capping Machine?

A capping machine is industrial packaging equipment that places, tightens or press-fits the caps of filled containers automatically or semi-automatically. It is generally positioned after the liquid filling machine and closes filled containers without interrupting the line.

The capping process includes sorting the caps, feeding them to the machine, placing them on the container mouth, tightening them to the correct torque and checking the capping result. On automatic systems, these operations can run together.

The operating method can change according to the cap construction. Screw plastic caps are generally tightened by rotation, while some metal caps, snap-on caps or tin lids can be closed by pressing or clinching. Cap and container samples should therefore be examined in detail before the machine is selected.

How Do Capping Machines Work?

On an automatic capping line, containers are carried to the capping section by a conveyor system. Caps are oriented in the cap feeding system and transferred to the machine. The fed cap is picked up by a mechanical or robotic system and placed on the container mouth.

Once the cap is positioned on the container, the tightening unit engages. The cap is tightened to the set force using wheels, balls, a capping head or servo-controlled systems. This keeps the cap from being left too loose or over-tightened.

The correct tightening setting is particularly important for product safety. Caps that are insufficiently tightened can loosen during transport, cause product leakage, or allow the product inside the container to come into contact with the outside environment. Over-tightened caps can damage the cap, the container mouth or the thread.

On modern capping machines, values such as speed, tightening force, container height and cap size can be adjusted to the production requirements. With the necessary mechanical and software settings at product changeover, the same machine can be used for different containers.

Types of Capping Machines

When specifying the machine for a production line, cap shape, container dimensions, hourly production capacity and the level of automation should be taken into account. The principal capping machines that can be selected for different requirements are as follows:

3-Wheel Spindle Capping Machines

3-wheel spindle capping machines are systems used to tighten screw caps in a controlled manner. Three separate tightening elements in contact with the circumference of the cap rotate the cap evenly on the container. They can be considered for production lines that use plastic caps of different diameters.

4-Wheel Spindle Capping Machines

On 4-wheel spindle capping systems, the cap is contacted at four separate points around its circumference. The balanced tightening arrangement helps achieve stable results on high-volume production lines. Machine settings can be arranged according to the cap diameter and the container height.

Single-Spindle Capping Machines

A single-spindle capping system works by gripping the cap with a dedicated capping head and closing it onto the container. It can be preferred in production where a specific torque value is important. With a tightening tool prepared to suit the cap geometry, a controlled and repeatable capping operation can be achieved.

Pick&Place Capping Machines

In Pick&Place systems, the cap is taken from the feeding area by an automatic mechanism or a robot and placed on the container mouth. After the cap is placed, the tightening unit engages and completes the capping operation.

Pick&Place systems can be used where the cap must be placed on the container at the correct angle and positioned with precision.

Robotic Capping Machines

Robotic capping machines use robot systems with different axes of motion to pick, transfer, position and close caps. Robotic solutions can be preferred for specially shaped caps, for applications where different containers are processed on the same line, or for projects that require precise motion control.

Robot systems can be designed as two-axis or four-axis according to the needs of the production line. Application-specific grippers make it possible to work with different cap types.

Rotary Capping Machines

Rotary capping machines are among the solutions used on lines with high production capacity. Containers are closed as they pass through defined stations on a rotating system. Suited to continuous production, rotary machines can provide important advantages for plants that require high speed.

Starwheel Capping Machines

On starwheel machines, containers are taken to the capping station by a special transfer mechanism known as a starwheel. The container is held stable and in the correct position during capping. Starwheel solutions can be used for containers that require precise positioning.

In Which Sectors Are Capping Machines Used?

Capping machines are used in many sectors that carry out packaged production. In the food and beverage sector, capping systems are required for packaging products such as water, milk, fruit juice, sauce, vinegar, syrup and edible oil.

In the cosmetics sector, the caps of shampoo, liquid soap, cream, lotion and personal care products need to be closed correctly. In the chemical and cleaning sector, leak-tight packaging of detergents, disinfectants, surface cleaners and other chemical products is important.

For products such as mineral oils, automotive chemicals, agrochemicals and liquid fertilisers, capping quality is critical for both product safety and transport conditions. In addition to selecting a container and cap suited to the chemical, materials resistant to the product may need to be used in the machine.

Capping machines can also be used in plants that manufacture pharmaceuticals, veterinary products, paint, construction chemicals and industrial liquids.

Advantages of an Automatic Capping Machine

An automatic capping machine creates a faster and more standardised production process. Tightening every cap with a similar force helps reduce differences in capping between products.

The principal advantages of automatic capping machines are as follows:

• Helps increase the capacity of the production line.

• Reduces the need for manual labour.

• Tightens caps with a standard force.

• Lowers the risk of faulty or crooked capping.

• Helps prevent product leakage.

• Makes packaging quality more consistent.

• Can be integrated with filling and labelling machines.

• Can be customised for different caps and containers.

• Can offer an adjustable production setup at product changeover.

• Supports continuity of production.

A correctly engineered capping system raises production speed, and it can also reduce product losses caused by faulty packaging and the need for rework.

What Should Be Considered When Selecting a Capping Machine?

Cap diameter, height, material, thread form and geometry should be evaluated in detail, together with production speed. Whether the container is glass, plastic or metal can also affect the tightening system to be used.

The target hourly capacity, the automation level of the production line and other containers that may be used later should also be included in the selection process. On lines where more than one container size will be used, machines that can be adjusted easily and that allow format changeover should be preferred.

How caps are fed to the machine is also important. There are differences in capacity and investment between systems in which the operator feeds caps manually and automatic cap sorting and feeding systems. At high production speeds, automatic cap feeding systems can support continuity of production.

Compatibility with the existing filling and labelling line, conveyor height, direction of travel and the layout space within the plant should also be assessed before the project.

Capping Solutions for Your Production Line

Every product and packaging line has different requirements. Selection of a capping machine should be treated as an application-specific engineering process.

Arsanmak develops 3-wheel spindle, 4-wheel spindle, single-spindle, Pick&Place, robotic, rotary and starwheel capping machines for containers used in different sectors. When the machine is designed, container and cap samples, target production capacity, line layout and automation expectations are taken into account.

When a new production line is installed, the capping machine can be engineered together with the liquid filling, conveyor and labelling systems. On existing production lines, integration of the capping system into the line can be planned after the appropriate technical review.

To obtain information about capping machine options suited to your plant's production capacity, container characteristics and cap type, you can contact Arsanmak and request a quotation for a machine solution specific to your application.