Browse > Article
http://dx.doi.org/10.5762/KAIS.2020.21.2.634

Study of lubrication and rheological properties of urea grease with respect to PTFE powder addition  

Son, Kihun (LUBCHEM Co., Ltd.)
Lee, Dongkyu (ORCHEM Co., Ltd.)
Lee, Youngseok (JINYANG OILSEAL Co., Ltd)
Woo, Jaegu (LUBCHEM Co., Ltd.)
Ha, KiRyong (Department of Chemical Engineering, Keimyung University)
Publication Information
Journal of the Korea Academia-Industrial cooperation Society / v.21, no.2, 2020 , pp. 634-643 More about this Journal
Abstract
In this study, the rheological and tribological properties of urea grease were studied according to the type and amount of polytetrafluoroethylene (PTFE) powders added to the urea grease, which is the most widely used among solid lubricants, to develop an optimal lubrication system. Urea grease was synthesized using 4,4'-methylenebis(phenyl isocyanate)(MDI), oleylamine, and cyclohexylamine, and PTFE powders prepared by dispersion or suspension polymerization process were then added. The basic rheological and tribological properties of the prepared greases were compared. The worked penetration numbers of urea grease decreased with increasing amount of PTFE powders, but both PTFE powders caused no significant changes in heat resistance and copper corrosion resistance. The shear viscosity increased with increasing PTFE powder content, and the dispersion-type PTFE powder was more effective in increasing the viscosity. In the value of the loss coefficient = 1, the shear stress was higher for the grease containing PTFE powders than the non-PTFE added grease, and the dispersion-type PTFE-added grease showed higher viscosity than the suspension-type PTFE-added grease. Finally, urea grease was found to have a low-performance improvement in terms of wear reduction effects by adding PTFE powders, but the load-bearing performance was up to 2.5 times higher for the dispersion-type PTFE and five times higher for the suspension-type PTFE.
Keywords
Lubricants; Grease; Suspension-type PTFE; Dispersion-type PTFE; Tribology;
Citations & Related Records
연도 인용수 순위
  • Reference
1 H. Czichos, Basic Tribological Parameters, Friction, Lubricant and Wear Technology, ASTM handbook, Vol.18, 474, 1992.
2 ASTM Standards on Petroleum Products and Lubricants Method D288-61.
3 K. H. Choung, Lubrication Engineering, KTC pp. 152, 1991.
4 Delgado M. A., Valencia C., Sanchez M. C., Franco J. M. and Gallefos C., "Influence of soap concentration and oil viscosity on the rheology and microstructure of lubricating grease", Ind. Eng. Chem. Res., Vol.45, pp. 1902-1910, 2006. DOI:http://dx.doi.org/10.1021/ie050826f   DOI
5 Okaniwa T., Kimura H,, "Effects of Various Factors on Properties of Lithium Complex Grease", Kyodo Yushi Co., Ltd., Vol.61, No.3, pp. 18-24, 1996.
6 R. Adams, John R. Johnson and Charles F. wilcox, "Laboratory Experimets in ORGANIC CHEMISTRY", 7th, pp. 2274, 1979 DOI:https://doi.org/10.1021/ed057pA26
7 T. Mang, "Lubricants and Lubrication" Wiley-vch, Second, completely Revised and Extended Edition, pp.694, 2007. DOI:https://doi.org/10.1002/9783527610341
8 H. H. shim, O. K, Kwon, K, H Lee, B, H, Kim, "Effects of Composition Ratio and Temperature on Friction and Wear of PTFE-Polyimide Composites", Tribology and lubricants, Vol.12, No.3, pp. 55-62, 1996. DOI:https://doi.org/10.9725/kstle.1996.12.3.055
9 Solvey, "Polymist(R) & Algoflon(R) PTFE Micronized Powders", 2016 Solvay Specialty Polymers Technical Bulletin, pp. 9-14, 2016.
10 KOREA Standards, Lubricating grease, KS M 2130.
11 ASTM Standards on Petroleum Products and Lubricants Method D2266-11.
12 ASTM Standards on Petroleum Products and Lubricants Method D2596-15.
13 DIN Standards on Testing of lubricants Method DIN 51810-1:2017.
14 Rahimi, S. Natan, B. "Numerical Solution of the Flow of Power-Law Gel Propellants in Converging in Converging Injectors," Propellants, Explosives, Pyrotechnics, Vol.25, pp. 203-212, 2000. DOI:https://doi.org/10.1002/1521-4087(200009)25:4<203::AID-PREP203>3.0.CO;2-E   DOI
15 M.Sugimoto, Y. Suzuki, K. Hyun, K. H. Ahn, T. Ushioda, A. Nishioka, T. Taniguchi, and K. Koyama, "Melt rheology of long-chain-branched polypropylenes", Rheol. Acta, Vol.46, pp. 33, 2006. DOI:https://doi.org/10.1007/s00397-005-0065-z   DOI
16 J. M. Madiedo, J. M. Franco, C. Valencia, M. C. Sanchez, C. Gallegos, J., "Modeling of the nonlinear rheological behavior of lubricating grease at low shear rates." Tribol, Vol.122, pp. 590-596, 2000. DOI:https://doi.org/10.1115/1.555406
17 T. Mang, "Lubricants and Lubrication" Wiley-vch, Second, completely Revised and Extended Edition, pp. 652, 2007. DOI:https://doi.org/10.1002/9783527610341
18 DIN Standards on Testing of lubricants Method DIN 51810-2:2017.