Choosing a linear bearing is not an easy task, since its requirements depend on the applications you want to give it. A bearing is not the same for transport systems or for precision devices; whereas in the first case We are looking for precision and speed, in the second case what is being sought is precision and stiffness.

In this article you can discover the most important problems you may encounter when using a linear bearing, the most outstanding advantages And a guide with useful tips to choose an element with these characteristics.

What are linear bearings?

Los linear bearings are rolling elements for translational movements. As in the case of rotary bearings, It is distinguished if the forces that are produced are transmitted by rotating elements or by friction elements.

They are composed of a plastic cage What if combines with steel rolling segments hardened for guiding ball sets. They exist different types of bearings in the market that provide different advantages.

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Types of linear bearings and their advantages

These are the different types of linear bearings that exist:

Linear ball bearings:

These offer the lower friction and the two featured products are traditional linear recirculation ball bearings and linear guides.

Traditional linear recirculation ball bearings:

They are used with hardened and ground axles. The balls have a very small point contact area that allows a friction with very low tread. However, having a small contact area means that they exert a large force on the shaft. Therefore, it is basic that they are only used on hardened axles.

These bearings can be open or closed:

• Open linear bearings: These have a small opening and are used in applications where multiple shaft supports or full shaft support are needed to prevent the shaft from flexing.
• Closed linear bearings: These are those bearings that are completely closed.

Applying this type of linear bearings in projects provides different advantages such as:

• Reduction Of the friction and the noise.
• Its closed design also makes it possible to unlimited range.
• Capabilities of high load and long lifespan.
• Simple structure and high reliability.
• High performance and replacement capacity.
• Easy lubrication (both oil and grease can be applied)

Linear guides

These are also bearings linear ball circulation, but they run on a profiled rail. The ball groove in these rails usually has Gothic arch shape to maximize load capacity. The rail must be sturdy to prevent the balls from deforming it. These guides offer a precise linear motion.

Apply this type of linear bearings In the projects it provides different profits such as the following:

• Up to 40% cheaper than recirculation ball bearings
• 100% lubrication-free and maintenance-free
• Hygienic and corrosion resistant
• Wear-resistant
• Insensitive to dirt, dust and moisture
• Extremely quiet operation
• High lifespan

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Roller bearings

Los roller bearings have a higher basic load capacity than ball bearings with an equivalent size. However, are less tolerant of lateral forces. Roller bearings are mainly used as roller chains, but they can also be used in cross roller guides.

Roller chain

Son bearings that roll in their outer diameter along a track. Normally, they contain rollers as a rolling element, but sometimes they can contain balls (usually when radial load capacity is required). Los chain bearings are very versatile and come in many styles. The simplest is a bearing of full-service rollers, while others have profiled outer rings (V-shaped or concave). They can be attached using dowels, threaded studs The cubes weldable. Other designs incorporate a secondary axial roller to accommodate lateral loads (for example, combined roller bearings).

Roller guides

These are similar to ball guides, but offer a higher load capacity compared to the equivalent-sized ball version. As they are very Compact and Precise, are often used in medical applications.

Linear cross roller slide

They offer a very high accuracy And a high load capacity. However, the nature of their design makes them vulnerable to pollution and, consequently, they are predominantly used in aApplications for clean and clean rooms.

Plain bearings

These types of bearings have experienced a rapid evolution over the last 20 years with the development of low friction plastics. These bearings are made of plastic or ceramic and, even though oThey offer reduced friction, usually, the friction coefficient is much higher than the bearings of the rolling elements.

Plastic linear bearings

Son Cheap and offer reduced friction compared to other materials. Being free of rolling elements, there are less concern about product contamination, because of dirt, dust and debris. Nowadays, there is a wide range of plastics that offer different advantages.

Ceramic linear bearings

They offer similar attributes to linear plastic bearings. Son Silent and Soft and are traditionally available in the same sizes as traditional recirculation linear bearings and may not need lubrication. In addition, some allow rotational motion to be combined with linear motion.

Certainly, these bearings they provide a lot of benefits, but they also present Some problems if proper maintenance is not carried out or a proper use.

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The most common problems that may exist in the use of linear bearings

Linear bearings they have a high lifespan. However, they may be the source of the odd setback. On the one hand, the linear guides they have different problems such as peeling on the runways of the rail, which can be caused by misalignment of the assembly..

In addition, a insufficient lubrication It can cause the raceway wear and wear corrosion in balls. They can also be produced dents on the racetrack and a electrical corrosion or sparking due to an electrical current between the rail and the skate.

In the case of linear ball bearings, they can be produced problems due to lack of lubrication and the use of inappropriate lubricants. In addition, Contamination of the same by shavings And a poor handling can be the source of setbacks.

La corrosion, the Incorrect assembly And the fatigue may be another cause of significant alterations in the operation of this type of bearings.

What do you need to consider when choosing a linear bearing?

The characteristics of the linear bearing you buy condition its operation, so it's very important to choose the most suitable one for your project.

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If you are interested in purchasing a linear bearing for your business, you need to consider the following factors:

• Load capacity. This factor affects the weight supported and its duration.
• Lifespan. It is key to predicting if it will last for a short, medium or long period.
• Operating speeds. Its speed is conditioned by the operating temperature of the bearing.
• Acceleration. This factor is important when choosing between one bearing or another.
• Dimensions. The size of the bearing is important for it to fit properly in the transmission mechanism.
• Price. Cost is always a crucial and determining factor when choosing between one product or another, and it is also a crucial factor in the purchase of bearings.
• Service temperature. It is important to know this fact, since if it changes, the bearing conditions may vary. In this sense, it must be said that when working at high temperatures, the hardness of the material varies and the load that the bearing can withstand will be lower.

Linear bearings have aApplications in all industrial sectors, whether in general mechanics, packaging machines or handling units.

In particular, they are usually used in precision projects as in welding robots or assemblies, 3d printers and automation projects in packaging machines, packaging or palletizing machines.

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They can also be used in the World of car in projects such as test equipment; in the film industry on tripods to move the cameras; in some equipment for gyms; in projects of silent elevators for single-family homes; in machinery projects and test benches; and in projects in the world of medicine, mostly test benches.

Choosing the right linear bearing is key to the functioning of your project's mechanisms. Contact with our engineering equipment, I'm sure we can design that high performance gear motor that you need.