Advantages of extruded aluminum profiles

When we consider solutions made of aluminum, the first word that comes to mind is lightness. Nothing could be truer with a specific weight of 2.7 g/cm³, but if we dig a little deeper, we can discover several other strong points, such as versatility, ductility and resistance to corrosion. We can also find surprising results when we compare the load capacity to that of steel!

Introduction
The anthropomorphic robot market is growing steadily year after year in several different applications, and the need to expand the range of action of these machines with a seventh axis is also growing. Having the option of moving the robot along a new axis allows us to increase productivity and efficiency. For this reason, Rollon has developed a complete range of seven models in various sizes and with different capacities. All these machines can work with anthropomorphic robots in a range of factories, handling loads of up to 2000 kg. Rollon’s Seventh Axis solutions are all made with extruded aluminum profiles, assembled with connecting crosspieces that endow the system with maximum rigidity. They use rails with recirculating ball bearings and drives that run either with a ground rack with inclined teeth or a toothed belt.

Aluminum, steel, and the load capacity

Aluminum is the distinctive material of Rollon’s solutions, in a market where many solutions are made of steel. It’s perfectly natural to ask: “In terms of load capacity, how do seventh axis systems with aluminum profiles compare to steel systems?”. Obviously, steel offers greater mechanical resistance overall, but aluminum, being extremely malleable and flexible, can be extruded to make highly elaborate geometries, which are excellent for guaranteeing
the greatest moment of inertia and the least weight possible.

On the other hand, steel drawing – or steel processing in general – does not allow the construction of sufficiently complex pieces to guarantee comparable results. This is why aluminum seventh axis systems can quickly gain ground on steel solutions with regard to load capacity, but with an important extra feature: they weigh two and a half times less. The Seventh Axis range from Rollon can manage loads of up to 2000 kg.

Now, let’s look at the other advantages of aluminum profiles.

Lightness
As we said before, lightness is undoubtedly the most important plus: a light seventh axis offers several application specific advantages, starting with lower transport costs. Moreover, the assembly of a solution weighing almost one third less than a steel solution is inevitably faster, easier, and most importantly, safer. Lastly, lightness is an important competitive advantage in all applications that involve a ceiling or wall mounted system instead of a floor-standing seventh axis system. In these cases, it is not necessary to add a heavy seventh axis in steel to the weight of the robot. Ceiling and wall mounted configurations are very common in painting and welding applications, in the automotive industry, and in other industrial areas.

Resistance to corrosion: 

Steel in its most common form, carbon steel, corrodes on contact with water or in a humid atmosphere. This is why steel solutions destined for harsh environments require surface treatments that make them resistant to corrosion. These treatments offer different degrees of protection and, naturally, affect the costs of the finish solution and the delivery times. Aluminum oxidizes naturally on contact with air, and is not altered by humidity: it is resistant to corrosion and does not require any other treatment. A simple neutral anodizing treatment is usually done, purely for aesthetic reasons. Solutions with protected profiles The malleability of aluminum makes it possible to create different geometries through extrusion. The “C” profile is extremely functional. This is a square profile with an opening where a belt and carriage can slide.This shape makes it possible to place the rail inside the profile. The final result is acompletely closed unit that contains all the elements of the system. This solution is particularly interesting when it is necessary to isolate the seventh axis from the environment (to protect it from dust, residue, liquids or other contaminants), or on the contrary, when the environment must be isolated from the seventh axis in clean rooms or sterile environments where it is crucial to avoid dispersing particles. Obviously,  constructions of this level of complexity cannot be made with the drawing process used to make steel profiles.