A Possibility to Improve Resistance of Cast-iron Hydraulic Valves to Cavitation Wear

• Autorzy: Orłowicz A. W. , Tupaj M. , Mróz M. , Kupiec B. , Jacek M. , Radoń M.

Identyfikatory

DOI

10.24425/123628

• Języki publikacji: EN

Abstrakty

EN

A common problem encountered in hydraulic valves is a progressing deterioration of tightness of their water flow cutting-off seats. The seats are provided usually with a copper-alloy insert joined mechanically with cast-iron valve housing. The problem of unreliability of such joints can be solved by providing surface of the seat with a coating, deposited with the use of HVOF method and resistant to abrasive and cavitation wear. The tests were carried out for a sealing-draining seat insert made of CuZn39Pb2Al brass used to date and a specimen taken from the cast-iron valve housing which was the substrate for a plasma-sprayed coating of powder containing 86.1% Cr, 7.2% Ni, and 6.7% C. The coating, 345 ± 15 μm thick, was characterized with good quality of bonding with cast-iron substrate and high compactness of the material. The cavitation wear test on materials used in the study were carried out with the use of Vibra-Cell ultrasonic liquid processor (Sonics) equipped with a piezoelectric probe operating at the frequency of 20 kHz. Based on profilograms taken along a line crossing centers of cavitation craters, measurements of the height parameter R_t, and microscopic observations of surfaces it has been found that the coating plasma-sprayed onto substrate of nodular cast iron demonstrated higher resistance to cavitation compared to copper-alloy inserts used so far in cast-iron hydraulic valves. Cavitation craters on the material used typically for valve seats to date were more distinctly outlined and deeper compared to craters observed on the coating. Larger were also sizes of local tear-outs which resulted in larger difference between the peaks line and the valleys line.

Słowa kluczowe

EN

cast iron; hydraulic valve; cavitation wear; plasma sprayed coating; sealing ring

PL

żeliwo; zawór hydrauliczny; zużycie kawitacyjne; powłoka natryskiwana plazmowo; pierścień uszczelniający

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2018
• Tom: Vol. 18, iss. 4
• Strony: 31--34
• Opis fizyczny: Bibliogr. 13 poz., rys., tab., wykr.

Twórcy

autor

Orłowicz A. W.

• Rzeszow University of Technology, al. Powstańców Warszawy 12, 35-959 Rzeszów, Poland

autor

Tupaj M.

• Rzeszow University of Technology, al. Powstańców Warszawy 12, 35-959 Rzeszów, Poland

autor

Mróz M.

• Rzeszow University of Technology, al. Powstańców Warszawy 12, 35-959 Rzeszów, Poland

autor

Kupiec B.

• Rzeszow University of Technology, al. Powstańców Warszawy 12, 35-959 Rzeszów, Poland

autor

Jacek M.

• Rzeszow University of Technology, al. Powstańców Warszawy 12, 35-959 Rzeszów, Poland

autor

Radoń M.

• Rzeszow University of Technology, al. Powstańców Warszawy 12, 35-959 Rzeszów, Poland

Bibliografia

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• [3] Adamski, M. (2003). How to avoid cavitation — circulation pumps. Rynek Instalacyjny. 11. (in Polish).
• [4] Bagiński, J. (1998). Cavitation in water supply and heat engineering systems. Poznań: Wyd. Politechniki Poznańskiej. (in Polish).
• [5] Jamróz, S. (2015). Critical flow-related phenomena and ways to suppress them. Armatura i Rurociągi. October-December 10,12. (in Polish).
• [6] Romo, S.A., Santa, J.F., Giraldo, J.E. & Toro, A. (2012). Cavitation and high-velocity slurry erosion resistance of welded Stellite 6 alloy. Tribology International. 47, 16-24.
• [7] Kwak, C.F., Man, H.C. & Cheng, F.T. (2001). Cavitation erosion–corrosion behaviour of laser surface alloyed AISI 1050 mild steel using NiCrSiB. Materials Science and Engineering. A303, 250-261.
• [8] Hattori, S. & Mikami, N. (2009). Cavitation erosion resistance of Stellite alloy weld overlays. Wear. 267, 1954-1960.
• [9] Stella, J., Schüller, E., Heßing, C., Hamed, O.A., Pohl, M. & Stöver, D. (2006). Cavitation erosion of plasma-sprayed NiTi coatings. Wear. 260, 1020-1027.
• [10] Bitzer, M., Rauhut, N., Mauer, G. Bram, M., Vaßen, R., Buchkremer, H.P., Stöver, D. & Pohl, M. (2015). Cavitation – resistant NiTi coatings produced by low pressure plasma spraying (LPPS). Wear. 328-329, 369-377.
• [11] Wang, Y., Stella, J., Darut, G., Poirier, T., Liao, H. & Planche, M.P. (2017). APS prepared NiCrBSi-YSZ composite coatings for protection against cavitation erosion. Journal of Alloys and Compounds. 699, 1095-1103.
• [12] Malek Ghaini, F., Ebrahimnia, M. & Gholizade, Sh. (2011). Characteristics of crack in heat affected zone of ductile cast iron in powder welding process. Engineering Failure Analysis. 18, 47-51.
• [13] Ebrahimnia, M., Malek Ghaini, F., Gholizade, Sh. & Salari, M. (2012). Effect of cooling rate and powder characteristics on the soundness of heat affected zone in powder welding of ductile iron. Materials and Design. 33, 551-556.

Uwagi

PL

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2018).