1. Pressure regulators problem.

2. 3.12.2004S.Konovalov "Pressure regulators." Tested gas componentSample #TestedTest resultcomments Pressure regulator Bachofen Instrum AG LPRI 20487.09.04-19.09.0450% after 115h in all zone> 40 %/100 h 20496.10.04-11.10.0450% after 93h in all zone 50 %/100 h 2049-2 after flushing and heating25.10.04- 13.11.04<2% after 220hElectronegative impurities 2049-3 more flushing at room temperature 13.11.04-24.11.045-8% after 232h2-3 %/100 h 1060Slight Si contaminationChemical test Membrane for Bachofen pressure regulator 20568.1104-12.11.048-12% after 70h14 %/100 h Pressure regulator Zimmerli ZM-R25S 204523.08.04-6.09.0425% after 254h10 %/100 h 20506.10.04-15.10.0413% after 185h7 %/100 h 2050-2 after flushing25.10.04-1.11.0412% after 140h8.6 %/100 h 2052 after flushing25.10.04-1.11.0425-45% after 140h in all zone18-32%/100h 2053 after flushing25.10.04-1.11.04Up to 5-8% after 220h3%/100h 205716.11.04-25.11.0413% after 190h10-15%/100h* 10582.07.04No Si, organicsChemical test Viton membrane of Zimmerli regulator type #2053 20548.11.04-12.11.046-9% after 70h11 %/100 h Teflon parts and seat (Viton) of Zimmerli regulator type #2053 20558.11.04-18.11.04No ageing after 212h PTFE membrane of Zimmerli pressure regulator 205815.11.04-2.12.04No ageing after 220h Pressure regulator Zimmerli with PTFE membrane ?

3. 3.12.2004S.Konovalov "Pressure regulators." One more pressure regulator was tested Zimmerli ZM-R25S sample #2057 Ageing rate is 10-15 %/100h – more or less the same as in the previous tests. 3 Bachofen and 5 Zimmerli pressure regulators have bean tested in 13 tests. All tested samples of Bachofen and Zimmerli pressure regulators gave ageing.

4. 3.12.2004S.Konovalov "Pressure regulators." Which parts of p-regulators are responsible for the ageing? Metal parts. Membranes. Other non metal parts. Grease, lubricants… Solvents used for cleaning.

5. 3.12.2004S.Konovalov "Pressure regulators." Tests of membranes. Viton membrane for Bachofen pressure regulator – ageing 14 %/100h Viton membrane of Zimmerli regulator type #2053 ageing 11 %/100h Teflon parts and seat (viton) of Zimmerli regulator type #2053 No ageing after 212 hours. Viton membranes are the main sources of ageing.

6. 3.12.2004S.Konovalov "Pressure regulators." Which material can be used for diaphragms instead of viton? PTFE membrane of Zimmerli pressure regulator was tested. NO ageing after 220 hours.

7. 3.12.2004S.Konovalov "Pressure regulators." Do we have other sources of Si except membranes? We are planning to test Zimmerli pressure regulator with teflon membrane. It is flushing since Tuesday and will start irradiation on Monday.

8. 3.12.2004S.Konovalov "Pressure regulators." Pressure regulator Bachofen Instrum AG LPRI sample 2049 after flushing and heating gave electronegative impurities. The concentration of electronegative impurities decreased during the test. Gas gain v.s. gas flow Sample 2049-2 No ageing with electronegative impurities

9. 3.12.2004S.Konovalov "Pressure regulators." Ageing processes started again when concentration of electronegative impurities decreased. Electronegative impurities removed