Effect of expansion coefficient difference between machine tool and workpiece to the thermal deformation induced by room temperature change

Recently, various precision products such as lenses or mirrors are produced by the ultra-precision machine tools. Then, the single-point diamond cutting is mainly carried out using the ultra-precision machine tool. In order to generate the high accuracy and high quality machined surfaces, the high stiffness and precise rotational accuracy of the spindle is required for the ultra-precision machining tools. The water driven spindle had been developed for the precision machine tool spindle. This spindle is driven by the generated torque due to the water flow power. Then, the rotational speed can be controlled by the supplied flow rate of water. In addition, the spindle has the water hydrostatic bearings that achieve the high bearing stiffness and precise motion accuracy. Furthermore, it is expected that the water driven spindle has the high thermal stability since the water with low viscosity is used as a coolant media. If the thermal deformation of the spindle is caused during the machining process, the deformation degrades the machining accuracy, accordingly. Thus, it is desirable that the thermal deformation and the temperature change of each part of the spindle and machine tool structure can be controlled and minimized during machining process. In this paper, in order to investigate the thermal stability of the water driven spindle, the measurement tests of the temperature of the water driven spindle were carried out. In addition, the power loss due to the water viscosity between the rotor and the casing of the spindle is calculated. As a result, this paper considers the temperature change and considers the thermal stability of the water driven spindle from the results of experiments.

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A Thermal Deformation Test Technique Robust to Change in Room Temperature Using Multiple Periodic Heating

AIAA Scitech 2021 Forum ◽

10.2514/6.2021-1032 ◽

2021 ◽

Author(s):

Takahiko Shibata ◽

Kosei Ishimura ◽

Tomoyuki Miyashita

Keyword(s):

Thermal Deformation ◽

Room Temperature ◽

Periodic Heating ◽

Test Technique ◽

Deformation Test

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Study on Self Compulsory Cooling for Reducing Thermal Deformation of Machine Tool.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.66.3150 ◽

2000 ◽

Vol 66 (649) ◽

pp. 3150-3155

Author(s):

Ikuo TANABE ◽

Koji MATSUSHITA ◽

Hisatoshi NAKAHASHI ◽

Minh TRUONG HONG

Keyword(s):

Machine Tool ◽

Thermal Deformation

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Effect of Supply Cooling Oil Temperature in Structural Cooling Channels on the Positioning Accuracy of Machine Tools

Journal of Mechanics ◽

10.1017/jmech.2019.29 ◽

2019 ◽

Vol 35 (6) ◽

pp. 887-900 ◽

Cited By ~ 2

Author(s):

K.-Y. Li ◽

W.-J. Luo ◽

M.-H. Yang ◽

X.-H. Hong ◽

S.-J. Luo ◽

...

Keyword(s):

Machine Tool ◽

Thermal Deformation ◽

Thermal Error ◽

Machining Accuracy ◽

Feed System ◽

Positioning Accuracy ◽

Cooling Channels ◽

Position Accuracy ◽

Machine Tool Accuracy ◽

Volume Method

ABSTRACTIn this study, the thermal deformation of a machine tool structure due to the heat generated during operation was analyzed, and embedded cooling channels were applied to exchange the heat generated during the operation to achieve thermal error suppression. Then, the finite volume method was used to simulate the effect of cooling oil temperature on thermal deformation, and the effect of thermal suppression was experimentally studied using a feed system combined with a cooler to improve the positioning accuracy of the machine tool. In this study, the supply oil temperature in the structural cooling channels was found to significantly affect the position accuracy of the moving table and moving carrier. If the supply oil temperature in the cooling channels is consistent with the operational ambient temperature, the position accuracy of the moving table in the Y direction and the moving carrier in the X and Z directions has the best performance under different feed rates. From the thermal suppression experiments of the embedded cooling channels, the positioning accuracy of the feed system can be improved by approximately 25.5 % during the dynamic feeding process. Furthermore, when the hydrostatic guideway is cooled and dynamic feeding is conducted, positioning accuracy can be improved by up to 47.8 %. The machining accuracy can be improved by approximately 60 % on average by using the embedded cooling channels in this study. Therefore, thermal suppression by the cooling channels in this study can not only effectively improve the positioning accuracy but also enhance machining accuracy, proving that the method is effective for enhancing machine tool accuracy.

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A Robust Fiber Bragg Grating Hydrogen Gas Sensor Using Platinum-Supported Silica Catalyst Film

Journal of Sensors ◽

10.1155/2018/5810985 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Marina Kurohiji ◽

Seiji Ichiriyama ◽

Naoki Yamasaku ◽

Shinji Okazaki ◽

Naoya Kasai ◽

...

Keyword(s):

Fiber Bragg Grating ◽

Gas Sensor ◽

Temperature Change ◽

Catalytic Combustion ◽

Room Temperature ◽

Precursor Solution ◽

Hydrogen Gas ◽

Combustion Heat ◽

Catalyst Film ◽

Sensor Device

A robust fiber Bragg grating (FBG) hydrogen gas sensor for reliable multipoint-leakage monitoring has been developed. The sensing mechanism is based on shifts of center wavelength of the reflection spectra due to temperature change caused by catalytic combustion heat. The sensitive film which consists of platinum-supported silica (Pt/SiO2) catalyst film was obtained using sol-gel method. The precursor solution was composed of hexachloroplatinic acid and commercially available silica precursor solution. The atom ratio of Si : Pt was fixed at 13 : 1. A small amount of this solution was dropped on the substrate and dried at room temperature. After that, the film was calcined at 500°C in air. These procedures were repeated and therefore thick hydrogen-sensitive films were obtained. The catalytic film obtained by 20-time coating on quartz glass substrate showed a temperature change 75 K upon exposure to 3 vol.% H2. For realizing robust sensor device, this catalytic film was deposited and FBG portion was directly fixed on titanium substrate. The sensor device showed good performances enough to detect hydrogen gas in the concentration range below lower explosion limit at room temperature. The enhancement of the sensitivity was attributed to not only catalytic combustion heat but also related thermal strain.

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Bulk Transition Elements Based Materials for Magnetic Cooling Application

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.170.248 ◽

2011 ◽

Vol 170 ◽

pp. 248-252 ◽

Cited By ~ 4

Author(s):

Mohamed Balli ◽

Osmann Sari ◽

L. Zamni ◽

A. Robert ◽

J. Forchelet ◽

...

Keyword(s):

Magnetic Field ◽

Composite Material ◽

Powder Metallurgy ◽

Magnetocaloric Effect ◽

Temperature Change ◽

Room Temperature ◽

Test Bench ◽

Transition Elements ◽

Magnetic Systems ◽

Magnetic Cooling

In this paper we investigate the performances of two bulk magnetocaloric refrigerants based on La(Fe,Co)13-xSix and prepared by powder metallurgy. Both materials were developed especially for a magnetic cooling machine. We have determined the magnetocaloric effect in term of temperature change under magnetic field using a test-bench with practical running conditions. ΔT was measured under 2 T and close to room temperature range. The obtained results will be compared with those of some reference materials reported in the literature. In addition, a composite material based on La(Fe,Co)13-xSix is proposed for magnetic systems using Ericsson and AMR cycles for refrigeration close to room temperature.

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Significantly enhanced room temperature electrocaloric response with superior thermal stability in sodium niobate-based bulk ceramics

Journal of Materials Chemistry A ◽

10.1039/c9ta00713j ◽

2019 ◽

Vol 7 (19) ◽

pp. 11665-11672 ◽

Cited By ~ 13

Author(s):

Ying Yu ◽

Feng Gao ◽

Florian Weyland ◽

Hongliang Du ◽

Li Jin ◽

...

Keyword(s):

Thermal Stability ◽

Temperature Change ◽

Room Temperature ◽

Large Temperature ◽

Sodium Niobate ◽

Bulk Ceramic

This work simultaneously achieved a large temperature change (ΔT, ∼0.70 K) at room temperature and ultra-stable ΔT(±1.4% variation between 300 K with 380 K) in 0.78NaNbO3–0.22BaTiO3bulk ceramic.

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Mathematical Model of Thermal Deformation in Precision Measurement and its Application

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.411.287 ◽

2011 ◽

Vol 411 ◽

pp. 287-291

Author(s):

Xiao Li Ma ◽

Huai Bo Qiang ◽

Xiao Zhou Feng

Keyword(s):

Mathematical Model ◽

Expansion Coefficient ◽

Thermal Deformation ◽

Steady Temperature ◽

Shape Factors ◽

Temperature Changes ◽

Cylindrical Shaft ◽

Volume Expansion Coefficient ◽

Geometric Size ◽

Material Line

As everyone knows, the temperature changes can cause the changes of mechanical geometric size. The thermal deformation obtained by traditional calculation formulas are approximate and linear, used in low precision requirement, however, if applied in high precision field, it is very limited. In this paper, by using the relations between crystal material line expansion coefficient and volume expansion coefficient, we will establish the thermal deformation mathematical model of cylindrical shaft and hole parts in the steady temperature, the model will consider the effects of the shape factors of parts on thermal deformation.

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