A Study on the Thermal Characteristics of the Grinding Machine Applied Hydrostatic Bearing

Abstract

In order to activate the high precision and multi-functional machine tool, adequate technical level of the high-precision products is required. The hydrostatic bearings is used as a method for producing the high-precision products. The hydrostatic bearing has a relatively small run-out compared to its shape error by fluid film effect in hydrostatic state similar to pneumatic bearing and has high stiffness, load capacity and damping characteristics. In this study, we conducted a study on the thermal deformation of the grinding machine that has a great influence on the machining accuracy of the product. The temperature of the front bearing is 10°C or higher than the temperature of the rear bearing. Thermal deformation of the spindle was found to be dependent on the temperature of the hydrostatic bearing and could identify the overall thermal characteristics of the grinding machine.

Thermal behavior of an improved face-grinding spindle: water-lubricated hydrostatic thrust bearing decreases temperature rise and increases axial stiffness

“…Until now, there has been an increasing amount of literature on thermal analysis of machine tool spindle system. The research objects mainly include spindles supported by rolling bearings [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19], spindles supported by hydrostatic bearings [20][21][22][23][24][25], and spindles supported by hydrodynamic bearings [26,27]. Modeling methods adopted mainly include: finite difference method [5,6], thermal resistance network method [3,4,7,16], bond graph method [18,19], and finite element method [8-15, 17, 20, 23-27].…”

“…Modeling methods adopted mainly include: finite difference method [5,6], thermal resistance network method [3,4,7,16], bond graph method [18,19], and finite element method [8-15, 17, 20, 23-27]. In their studies, temperature distribution and thermal deformation were calculated using the above methods [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][22][23][24][25][26][27]. Experimental research includes two aspects: one is measuring temperature rise of spindles by temperature sensors or thermal imagers [3, 4, 7-18, 20, 21, 23, 25-28]; another is measuring thermal deformation using displacement sensors [8-18, 20, 22, 24-26, 28].…”

Analysis of the impact of graphene nano-lubricating oil on thermal performance of hydrostatic bearing

“…In ultra-precision machines, thermal error is the largest source of error, accounting for approximately 70% of the total error (Chen et al, 2011). The high friction loss and heat generation of hydrostatic bearing affect the precision of ultra-precision machining (Kim et al, 2015). The temperature and pressure changes of the lubricating oil film will cause the deformation of the bearing bush and the spindle and then affect the static characteristics of the hydrostatic bearing and have a certain effect on the machining accuracy.…”

Investigations of the static and dynamic characteristics of the precision hydrostatic spindle with mid-thrust bearing under different loads

“…2 The mid-thrust bearing structure discussed in some studies can effectively improve the stiffness of the spindle without increasing its size. 3–6…”

“…Some researchers proposed to improve the spindle stiffness by increasing the diameter of the thrust bearing, which also increases the radial dimension of the spindle [2] . The midthrust bearing structure discussed in some researches can effectively improve the stiffness of the spindle without increasing the structure size of the spindle [3,4,5,6] . A mathematical analytical model of the flow field based on the Reynolds equation and the flow continuity equation was employed to accurately analyze the performance of the hydrostatic spindle with the coupled journal and thrust bearing [7] .…”