Air shaft

Expansion shaft: what is it and what types are available?

An expansion shaft is a key component of machinery used for winding and unwinding rolls and reels. The shaft ensures that a roll of material is clamped securely and precisely, allowing for controlled winding or unwinding. Expansion shafts are used in industries such as paper, film, plastics, packaging, and converting.

But what exactly is an expansion shaft, how does it work, and what types are there? In this article, we explain the key differences.

What is an expansion shaft?

An expansion shaft—also known as an expandable shaft, inflatable shaft, expansion mandrel, or air shaft—is a shaft inserted into the core of a roll or reel. Elements on the shaft expand to clamp against the inside of the roll's core.

With a pneumatic expansion shaft, this is typically achieved using air pressure. The expansion elements extend outward and make contact with the inner surface of the core. This allows the roll to be reliably driven or braked during the winding or unwinding process.

Consequently, an expansion shaft enables rolls to be installed and removed quickly, while ensuring the roll remains properly centered and securely clamped throughout production.

What is an expansion shaft used for?

Expansion shafts are used in a wide range of industrial applications involving the winding or unwinding of material rolls. Examples include:

paper and cardboard;
plastic and packaging film;
aluminum foil;
labels and other web materials;
slitting and converting machines;
coating lines;
winding and unwinding systems. The right expansion shaft depends on factors such as the weight and diameter of the roll, the material width, the required tension, and the method of mounting the shaft in the machine.

What types of expansion shafts are available?

Expansion shafts come in various designs. The main distinctions lie in how the shaft expands and the type of expansion element that makes contact with the roll core.

1. Expansion shaft with bars

An expansion shaft with bars uses multiple expansion elements that extend outward to secure the roll from the inside. This type is suitable for various applications and can be manufactured from materials such as aluminum or steel.

MBC Guttin describes this design as a solution for both single-lane and multi-lane unwinding. It allows the roll's position to be precisely aligned with the machine.

Advantages include:

relatively easy roll loading;
fast operation;
suitable for various roll widths;
available in different materials and designs;
suitable for a wide range of industrial applications.
2. Expansion shaft with lugs

An expansion shaft with lugs uses lugs that extend outward when expansion is activated. The lugs grip the inside of the core.

This design is often used when a firm grip and effective force transmission are important. MBC Guttin positions expansion shafts with lugs for applications involving heavier rolls and higher tension requirements.

3. Pneumatic expansion shaft

A pneumatic expansion shaft uses air pressure to activate the expansion elements. This allows the roll to be quickly clamped and released. Pneumatic expansion shafts are particularly well-suited for production environments where rolls are changed frequently. Furthermore, their operation can be integrated into the machine system.

MBC Guttin manufactures pneumatic and expansion solutions for industrial winding and unwinding applications, supplying them according to specific application requirements.

4. Expansion heads for cantilever applications

In addition to full-length expansion shafts, expansion heads are also available. These are used when the roll needs to be accessible from one side, such as in cantilever or overhanging setups.

MBC Guttin offers expansion heads based on various expansion principles for these applications. These solutions combine secure clamping with flexibility for specific machine configurations.

MBC Guttin expansion shafts

MBC Guttin is a French manufacturer of equipment for industrial winding and unwinding processes. The company produces items such as expansion shafts, expansion mandrels, pneumatic solutions, safety chucks, spreader rollers, and other components for winding systems. Manufacturing takes place in France.

MBC Guttin expansion shafts can be customized to suit specific machines and applications. According to the manufacturer, versions are available with diameters ranging from approximately 25.4 mm to 900 mm and lengths up to 9 meters. The shaft ends can also be configured to meet specific machine requirements.