Reliability & Maintenance

1. Reliability & Maintenance Paul C. Czarapata

2. Maintenance Time • The following chart represents the amount of time spent on maintenance during a 168 hour week. IT DOES NOT REPRESENT TOTAL DOWNTIME. Some periods overlap each other where the chart treats them linearly. It also does not represent availability for the same reason.

4. Status Update • Items Presented to DOE review • Voltage to Frequency Converters • Part of Quench Protection System in Tevatron • Plan called for replacement of Low Beta House Systems • All cards replaced, All crates replaced, All sense resistors modified. • Plan expanded to include all VFC’s in Tevatron

5. Status – cont. 2 • Overhaul Cryogenics Wet Engines • All overhauls are complete and should take us comfortably into the summer shutdown. • Cold Compressor Bearings • We have located an alternate source. • We have enough on hand but additional units are going to be ordered this FY.

6. Status – cont. 3 • Compressor Starters • Plan is to replace 2/3 this Fiscal Year 1/3 next year • First 1/3 are complete. • Second 1/3 will be done in Summer shutdown • Remainder will be ordered after October.

7. Status – cont. 4 • Other items are in process and showing good progress. We have handled the majority of the “critical” items.

8. Current Mysteries • Ground Motion • Traced to Domestic water well #1 • Magnet Motion • Traced to “bad” Tevatron magnet stands • Kicker Pre-fires • Company says “you have the best pre-fire rate of anyone using this configuration”

9. Motion in MI-8 line

10. Newest Dilema • Magnet Stands are rusting away. • Evidence of motion with Humidity (rust jacking) • Evidence of motion with high current in magnets • (weebolls wobble but they don’t fall down!) • Ed. Note weebolls were round bottom toys for small kids.

11. Tev Dipole Roll vs. I

12. Magnet motion vs. Quench and humidity

13. Magnet Stand in A16

14. Replacement of Stands • During the January shutdown we successfully replaced the A16-3 stand while the magnet was at nitrogen temperatures. The total number of stands needing replacement is now being cataloged for replacement when time is available. • We have placed additional tilt monitors in the Tevatron

15. And still more! • Linac Power Tubes • Use ~ 7 per year • This was based on 10,000 hr lifetime (typical) • Have had two failures after 2,000 hrs. • Compete with other labs for tubes • Military no longer uses this tube so volume is down for vendor. • Thoriated cathodes were changed from 2% to 1.5% due to OSHA difficulties.

16. Linac Tubes –cont. • Coming out of the January shutdown we had a tube that was believed to be only marginally useful (25%). • Two tubes due in February. Vendor says we will get 1 per month between now and August. We currently have Argonne’s spare installed.

17. Vulnerabilities • A list of items (vulnerabilities) was generated August of ’02. • These items would keep the lab down for at least 3 months should they fail. • The list was prioritized by likelihood and forwarded to DOE by Steve Holmes. • The list represented ~ $28.7M just in equipment.

18. Summary • We continue to battle an aging infrastructure for the machine components. • We will need high reliability and availability to meet the laboratories aggressive running schedule. • We will need increased funding to stay ahead of the problems.