Experimental Research Regarding the Influence of Hydraulic Resistances on the Hydrostatic Guideways Stiffness

Abstract:

A very important factor for the hydrostatic guideways is given by the presence of the restrictor on the supply circuit, whose hydraulic resistance may have important effects on the lubricant film behaviour and implicitly, on the static and dynamic stiffness of the system. This paper presents a new method of experimental research regarding the hydrostatic guideway stiffness, depending on the hydraulic resistances values which supply each pocket. During the experiments which approach the influence of the hydraulic resistances values of the restrictors on the hydrostatic guideway stiffness, a centered constant loads of 20, 50 and 100 [daN] was used. The experiments were carried out on an experimental setup composed of an open hydrostatic guideway, having the pocket dimensions of 150x88 [m, supplied with liquid under pressure through means of a pack of adjustable restrictors. The obtained experimental results are presented in both tabular and graphical form and constitute an experimental database which can be used by the machine tools designers and manufacturers. The paper contains recommendations regarding the usage of hydraulic resistances values depending on the machine tool type and size. Also, from the obtained results, recommendations can be made with regard to the type of restrictors to be used, so that the lubricant filtration grade is comprised between admissible values.

• Periodical: Applied Mechanics and Materials (Volume 657)
• Pages: 475-479
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.657.475
• Online since: October 2014
• Authors: Marius Pascu*, Gheorghe Stan
• Keywords: Guideway, Hydraulic, Hydrostatic Pocket, Restrictor, Stiffness

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