Different Types of Anti-Friction Guide-ways are
1. Hydro-Static Guideways
2. Aerostatic Guideways
1) Hydro-static Guide ways:-
In hydro-static guide ways, air or oil is pumped into the small pockets or cavities machined into the carriage or slides which are in contact with the guide way. The pressure of fluid gradually reduces to atmospheric pressure as it sweeps out from the pockets, through the gap between slide and guide ways. The hydro-static guide way provides almost a friction-less condition for the movement of the slide. For the efficient operation it is very important that the fluids and guide ways are kept clean and also the hydro-static guide ways need a very large surface area to provide adequate support.
2) Aerostatic GuideWays:-
In aerostatic guide ways, the slide is raised on a cushion of compressed air which entirely separates the slide and the guide way surface. The major limitation of this type of guide ways as a low stiffness which limits it use for positioning application only e.g. CMM and other measuring instrument. The selection of guide ways for a particular application basically depends upon the requirements of the load carrying capacity, damping property and the traverse speed. In order to get maximum benefit, most of the machine tool manufacturers make use of a combination of anti-friction and friction guide ways with Turcite/PTFE lining. Such combination improves load carrying capacity through the use of anti-friction guide ways and damping property by using guide ways.
In aerostatic guide ways, the slide is raised on a cushion of compressed air which entirely separates the slide and the guide way surface. The major limitation of this type of guide ways as a low stiffness which limits it use for positioning application only e.g. CMM and other measuring instrument. The selection of guide ways for a particular application basically depends upon the requirements of the load carrying capacity, damping property and the traverse speed. In order to get maximum benefit, most of the machine tool manufacturers make use of a combination of anti-friction and friction guide ways with Turcite/PTFE lining. Such combination improves load carrying capacity through the use of anti-friction guide ways and damping property by using guide ways.
