Prognosing the durability of polymer sealings

• Autorzy: Okularczyk W. , Kwiatkowski D.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The paper describes the phenomena connected with the sealing for water hydraulic systems. Design/methodology/approach: For the durability tests two types of sealings, made of three polymeric materials recommended for use in water hydraulics systems have been used. In all investigation arrangements the same guide elements have been used. The tests have been performed maintaining water pressure on the sealing at a level of p = 8±1 MPa and the average speed of the piston rod of v ≈ 0.35 m/sec. Water temperature during investigations was regulated within the range of Tmin = 291 K and Tmax = 305 K. The leakage was distributed to the measurement hoses with the internal diameter of 5mm. For the investigations, the working piston rod with ø 45 f7 with the following parameters has been used: Material: chromium-nickel steel AISI 431 (Cr=16.7%, Ni=2.08%) covered with hard chromium plating of ≥ 20 μm, micro-cracks number ≤ 5 000/mm2, Ra = 0.07 μm. Findings: Weibull method, thanks to its multifunctionality, helps to select elements for certain applications (required long failure-free mileages → high characteristic durability – sealings series 30413). Equipment which works sporadically → low characteristic durability but e.g. lower weight and sizes of sealing element – sealing series 30412. Practical implications: Within the confines of the given research concerning an optimal choice of piston rod sealing for water hydraulic systems, large dependence of the sealing durability on the properly chosen guide elements of the piston rod has been found. In extreme cases the durability changed even a few times. Originality/value: The Weibull method has been applied for assessment of durability and reliability of mechanical parts. A computer program has been used to compare two types of piston rod seals used in water hydraulic power systems. Durability limits have been estimated even though discontinued measurement data were used.

Słowa kluczowe

EN

engineering polymers; polymer properties; mechanical properties; statistic methods; polymer sealings; PE-UHMW; water hydraulic

PL

tworzywa konstrukcyjne; polimery konstrukcyjne; właściwości tworzyw; właściwości mechaniczne; metody statystyczne; uszczelnienia; PE-UHMW; hydraulika wodna

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 17, nr 1-2
• Strony: 125--128
• Opis fizyczny: Bibliogr. 10 poz., rys., tab., wykr.

Twórcy

autor

Okularczyk W.

• Institute of Polymer Processing and Production Management, Czestochowa University of Technology, Al. Armii Krajowej 19c, 42-200 Czestochowa, Poland

autor

Kwiatkowski D.

• Institute of Polymer Processing and Production Management, Czestochowa University of Technology, Al. Armii Krajowej 19c, 42-200 Czestochowa, Poland

Bibliografia

• [1] J. Migdalski i in.: Reliability handbook - base mathematics. Machines Industry Edition "WEMA" Warsaw 1982. (in Polish)
• [2] E. Otto i in.: Mathematics for building engineering and mechanical department. Tom III. PWN Warszawa, 1976. (in Polish)
• [3] www.versuchmethoden.de
• [4] Sz. Firkowicz: Product statistical test. WNT Warszawa, 1970.
• [5] H. Dette, Ch.I. Kozub: Bis das Getriebe kracht. Rubin 1/2000, S. 42-48. Der Ruhr - Universität Bochum. (in German)
• [6] www.tutech.de
• [7] www.weibull.com
• [8] Trostmann E.: Water hydraulics control technology. New York, Marcel Dekker, 1996.
• [9] K. Marcus, C. Allen: Effect of fillers on the friction and wear behaviour of ultra high molecular weight polyethylene during water-lubricated reciprocating sliding wear. Wear, 162-164 (1993), s.1091-1102.
• [10] H. Weiss.: Dichtungstechnik in wasserhydraulischen Anlagen. O+P Oelhydraulik und Pneumatik 43 (1999) Nr.2, s.104-106. (in German)