TY - CONF A1 - Weltschev, Margit T1 - Investigations on the degree of damage of polyethylene grades of heating oil storage tanks after a service life in excess of 25 years N2 - Plastic storage tanks for heating oil have been on the market since the early 1970s in Germany, mainly made from polyethylene grades. Tank manufacturers and experts examining the tanks recommend the replacement of the tanks to ensure the safety after a period of 30 years. The tank manufacturer is legally obliged to specify the service life of the tanks. Polyethylene is subject to ageing by alteration of the properties during its life cycle. A distinction is made between internal and external ageing processes. The internal ageing, such as the breakdown of internal stresses, post-crystallization, phase sepa-ration of multicomponent systems and plasticizer migration is attributed to thermodynamically instable conditions of the plastic material. The external ageing in form of stress cracking, fatigue cracking, thermooxidative degradation or swelling is based on physical or chemical effects of the environment of the polyethylene grade. The degree of ageing and the nature of the degradation process mainly depend on the chemical degradation of the polyethylene, the wall thickness of the tank and the environmental conditions. There are no results available on the long-term behaviour of the polyethylene grades used as materials for heating oil storage tanks, especially after a service life of more than 25 years. The aim of this investigation was the determination of the factual degree of damage in comparison to the uncontaminated polyethylene grades. Data on the melt flow rate (MFR) and density of the used polyethylene grades are available because the BAM was the competent authority for the approval of the plastic heating oil storage tanks until the end of the 1980s. The technical service of specialist companies for fuel tank disposal supplied tank sections from the bottom, the shell and the roof of 8 segregated heating oil storage tanks. Some of the tanks had been in service for more than 30 years. Two polyethylene grades mainly were used as materials for these tanks over this time. The determination of the MFR according to EN ISO 1133 and the FTIR spectroscopy followed standard test methods. The highest average percentage increase in the MFR was determined as 31- 43 % for the bottom section of the tanks, for both the inner shell and the outer shell. The lowest increase in MFR was measured for the top of the tank, with 6 - 12 % for the inner shell and 0 - 8 % for the outer shell. The tank shell sections had an average percentage increase in MFR of 10 - 33 % for the inner shell and of 14 - 40 % for the outer shell. The oxidative damage of the polyethylene grades was highest in the bottom area due to the permanent contact with the heating oil and degradation products. The microtome cuttings were analyzed with image-guided infrared microscopy in the transmission mode and confirmed the results obtained with the MFR measurements. In summary it can be concluded that the oxidative damage of the polyethylene grades after long-term contact with heating oil is relative low. T2 - EUROCORR 2017 CY - Prag, Czech Republic DA - 03.09.2017 KW - Polyethylene KW - Heating oil tanks KW - Service life KW - Degree of degradation PY - 2017 AN - OPUS4-41907 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Beständigkeitsbewertungen von Tank- und Behälterwerkstoffen in der Datenbank Gefahrgut und in der BAM-Liste T2 - Vortrag an der Bergischen Universität Wuppertal im FB Sicherheitstechnik im Seminar, ausgewählte Kapitel der Sicherheitstechnik/Materialkunde: Werkstoffe und Fertigungstechnik CY - Wuppertal, Germany DA - 2008-07-17 PY - 2008 AN - OPUS4-17739 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit A1 - Sturm, Christine T1 - Correlation between material parameters of high density polyethylene grades and the test performance behaviour of packagings T2 - EUROCORR 2008 CY - Edinburgh, Scotland, UK DA - 2008-09-07 KW - Dangerous goods packagings KW - HDPE grades KW - Material parameters KW - Design type tests PY - 2008 N1 - Serientitel: EFC-Event – Series title: EFC-Event IS - 299 SP - 1 EP - 12 PB - DECHEMA CY - Frankfurt am Main AN - OPUS4-17993 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Übertragbarkeit von Materialkennwerten auf das Baumusterverhalten von Verpackungen aus HDPE T2 - Kolloquium BAM CY - Berlin, Germany DA - 2008-10-01 PY - 2008 AN - OPUS4-18050 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weltschev, Margit T1 - Kostengünstiger Stahl mit hoher Beständigkeit KW - Duplexstahl KW - Korrosionsbeständigkeit KW - Tankwerkstoff KW - Gefahrguttransport KW - BAM-Liste PY - 2009 SN - 0944-6117 IS - 6 SP - 20 EP - 21 PB - Vogel CY - München AN - OPUS4-19640 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Weltschev, Margit A1 - Deuerler, F. ED - Suter, G. ED - de Rademaeker, E. T1 - Comparison of material parameters of polyethylene grades and the test performance behaviour of packagings for the transport of dangerous goods T2 - 13th International symposium on loss prevention and safety promotion in the process industries CY - Brugge, Belgium DA - 2010-06-06 KW - HDPE-Formstoffe KW - Werkstoffkennwerte KW - Spannungsrissbeständigkeit KW - Verpackungen KW - Baumusterprüfung PY - 2010 SN - 978-90-76019-291 VL - 02 SP - 383 EP - 386 CY - Brugge, Belgium AN - OPUS4-21451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Use of corrosion-resistant higher-alloyed metallic materials for the transport of dangerous goods in tanks T2 - 2nd Conference Steels in Cars and Trucks (SCT 2008) Future trends in steel development, processing technologies and applications" - Bringing the automotive, supplier and steel industries together CY - Wiesbaden, Germany DA - 2008-06-01 PY - 2008 AN - OPUS4-17697 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Vergleich der Materialeigenschaften von Polyethylenformstoffen mit dem Baumusterverhalten von Gefahrgutverpackungen; Übertragbarkeit von Kennwerten T2 - 12. Gefahrgut-Technik-Tage Berlin, BAM CY - Berlin, Germany DA - 2009-11-12 PY - 2009 AN - OPUS4-20390 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Comparsion of the resistance to oxidative degradation of polyethylene grades with the test performance behaviour of packagings for the transport of dangerous goods T2 - CORROSION 2010 CY - San Antonio, TX, USA DA - 2010-03-14 PY - 2010 AN - OPUS4-21052 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit A1 - Deuerler, F. T1 - Comparison of the resistance to oxidative degradation of polyethylene grades with the test performance behavior of packagings for the transport of dangerous goods T2 - NACE International Corrosion Conference 2010 CY - San Antonio, Texas, USA DA - 2010-03-14 KW - Dangerous goods packagings KW - Polyethylene grades KW - Resistance to oxidative degradation KW - Design type tests KW - FTIR spectroscopy PY - 2010 SP - 10044-1 - 10044-13 AN - OPUS4-21089 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -