**Travel to Japan**

11/23/2004

Dates of Travel: 11/8/04 to 11/19/04

Traveler:

Steve Marks, Mechanical Engineer, EGME12

Frank Zucca, EGME

Organization: Ernest Orlando Lawrence Berkeley National Laboratory

One Cyclotron Rd., Berkeley, CA 94720

Trip Number: Steve Marks: 200500478

Frank Zucca: 200500480

Destination: Spring-8

Purpose of Trip: The purpose of this trip was to observe final assembly,
vacuum preparation, and vacuum bake-out of the in-vacuum insertion
device (IVID) being built for installation in the ALS.

Contacts: Neomax: Mr. Okada

Spring-8: Dr. Tanaka

Facilities visited: Spring-8.

Abstract: Ten days were spent at Spring-8. During that time we observed
final assembly of the IVID vacuum chamber and RF transition, preparation
and vacuum bake-out. An ALS procedure document is being prepared for our
use should we need to repeat the bake-out process.

**Detailed Trip Report**

[Vacuum Assembly]{.underline}

The vacuum assembly was underway when we arrived on 11/10/04. Fig. 1
shows the state of the IVID when we arrived. Thermocouple wires can be
seen in the figure. Fig. 2 shows a close up of the magnetic structure
mounted within the vacuum chamber. The Cu/Ni conduction sheet can be
seen on the surface of the magnets in. The RF transition had not yet
been assembled and mounted.

![](media/image1.jpeg){width="5.989583333333333in"
height="4.481944444444444in"}

Figure 1. State of vacuum assembly on 11/10/04.

![](media/image2.jpeg){width="5.989583333333333in"
height="4.481944444444444in"}

Figure 2. Close up of magnetic structure mounted within the vacuum
chamber.

The RF transition was installed on 11/12/04. Fig. 3 shows the RF
transition end flange prior to installation. Fig. 4 shows the water
cooled flexible sheet installed on to the end of the magnetic structure.
The structure shown in Fig. 4 is shimmed on top and bottom so that it
mounts square with the end flange. This step is necessary to ensure that
all contacts in the conductive path are flush without any gaps
throughout the range of gaps. Fig. 5 shows the initial mounting of the
end flange. Note the gap along the bottom edge of the opening. The
flexible assembly was re-shimmed to remove this gap.

![](media/image3.jpeg){width="5.989583333333333in"
height="4.481944444444444in"}

Figure 3. RF transition end flage.

![](media/image4.jpeg){width="5.989583333333333in"
height="4.481944444444444in"}

Figure 4. RF transition water cooled flexible sheet.

![](media/image5.jpeg){width="5.989583333333333in"
height="4.481944444444444in"}

Figure 5. Initial installation of end flange.

[Vacuum Bake-out]{.underline}

A brief summary of the vacuum bake-out will be provided here. A detailed
bake-out procedure is being prepared as a separate document.

The vacuum bake-out consists of three phases: heating from room
temperature to steady state temperature, steady state bake-out, and cool
down. Temperature is controlled with two systems: a pressurized hot
water system that circulates water through the magnetic structure
cooling circuit, and heaters applied to the outer wall of the vacuum
vessel. Thermocouples attached to the in-vacuum magnetic structure and
the vessel are used for control and monitoring of temperatures during
the bake. Digital dial indicators are used to monitor relative expansion
between the vessel and the magnetic structure. Fig. 6 shows the system
wrapped and ready for bake. Fig. 7 shows the water circulation unit.
Fig. 8 shows the power supply rack for vessel heating.

![](media/image6.jpeg){width="5.989583333333333in"
height="4.481944444444444in"}

Figure 6. System wrapped for bake-out.

![](media/image7.jpeg){width="5.989583333333333in"
height="4.481944444444444in"}

Figure 7. Pressurized hot water circulation unit.

![](media/image8.jpeg){width="5.989583333333333in"
height="4.481944444444444in"}

Figure 8. Vessel heater power supply rack.

Initial heating is accomplished by increasing the circulating water
temperature. This is followed by increasing the temperature of the
vessel. Temperatures are increased by approximately 5°C every five
minutes. The rate of temperature rise in the water and the vessel are
varied to minimize the relative growth of the vessel versus the magnetic
structure. The goal is to keep the relative motion less than 2mm.

Steady state operation was achieved after approximately eight hours. At
steady state, the vessel wall temperatures were approximately 185°C,
in-vacuum backing beam temperatures were in range between 115°C and
125°C, and supply water temperature was 100°C. Demagnetization occurs at
about 140°C, so 125°C was established as the maximum temperature for the
magnetic structure. Fig. 9 shows the computer screen monitor of
temperatures, pressure, and dial gauge readings.

![](media/image9.jpeg){width="5.989583333333333in"
height="4.481944444444444in"}

Figure 9. Computer monitor screen.

After three days of bake-out, the system was cooled down. The cool down
operation was the reverse of the heating; temperatures were dropped
approximately 5°C every five minutes while monitoring the dial gauges.
The pressure prior to cool down was \~10^-8^ T. During cool down the NEG
pumps were activated and the ion pumps and gauges were turned on. NEG
activation consisted of heating to 450°C for 30 minutes.

[Schedule for Completion]{.underline}

-   Keep under vacuum until 12/2/04.

-   Purge with dry N 12/3/04.

-   Ship 12/10/04.