While the systems are similarly composed of a moving carriage and stationary base, instead of relying on the rotation of balls or cylinders to move a load, slide bearings slide or glide against each other providing low friction movement along the linear path. Slide bearings are typically made of a high performance polymer or a self lubricating material such as graphite that provides low resistance to motion.
The most common design for slide mechanisms is a sandwich style consisting of two plates of low-friction material in between metal backing plates. These plates are then usually attached to a high strength steel or metal bar that bears the weight of the load. Other system components may include shaft end supports and blocks as well as intermittent rail supports. Slide bearings are used in a range of industrial applications such as food processing and component manufacturing and testing. They are also used in oil and water transportation, steel fabrication, pipelines and more.
Factors to consider in the design of a precision linear bearing system include: the intended load of the bearing system, the temperatures and physical elements such as dust or dirt which the slide bearing might be exposed to, desired speed, size, and the dimensions of the area available for the motion system. Covers or bellows can be attached to a slide system to protect against dirt particles interfering with the low-friction properties of the bearing.
Slide bearings can be attached to a structure in a number of different ways, such as with bolts, industrial adhesives, and welding. Slide bearings offer the advantage of a quieter operation as there are no metal components rotating within the railings, the only sound produced will be that of the slides against each other which is minimal. Slide bearings also tend to last far longer than ball bearings or roller bearings especially if they are made of high performance materials.
As with any material exposed to elements of weather and wear and tear, the slide bearings will eventually need to be repaired or replaced, but they offer an ideal long lasting solution to low-friction movement needs. Compared to ball bearings and roller bearings, slide bearings are also more cost-effective, in part due to the longer lifespan, but also to the lower amount of materials required to construct the system as well as its broad versatility and adaptation capabilities.