The ALS’s next long shutdown period will commence in January, giving staff and technicians a chance to complete work critical to keeping the ALS at the scientific forefront. Between January 3 and March 20, 2017, the ALS will be closed to users so that facility, beamline, and accelerator upgrades and maintenance can be accomplished.
“We realize the hardship long shutdowns create for many of our staff and users,” says ALS Project and Facility Management Lead Steve Rossi. “During the shutdown, we will accomplish work that is critical for the livelihood of our scientific program and reliability of our accelerator. Some of these tasks represent only a single phase of multi-year shutdown plans. We make every effort to parse our major upgrades into smaller phases, but at some point we reach a portion of work that must be accomplished in its entirety.”
One of the biggest projects on the schedule in the upcoming shutdown is the replacement of the low conductivity water (LCW) cooling towers. The almost-30-year-old wooden cooling towers have reached the end of their service life. Because the ALS uses about 3,000 gallons per minute of LCW for cooling and requires great stability in terms of both flow and temperature, this is a critical need. The ALS has experienced tower reliability issues and unexplained losses in cooling capacity, which presents a significant risk to our operations. Berkeley Lab will replace the towers as the first phase of the project, while the remainder of the work will be completed in a future shutdown.
Another significant 2017 shutdown project will be the storage-ring low-level radio frequency controls. This is the final phase of a multi-year renewal of the ALS storage ring radio frequency (SRRF) system. The antiquated SRRF analog controls will be replaced with new digital controls, which involves the swap-out of many chassis with multiple critical terminations. This work requires significant commissioning time, so must be done during a long shutdown.
During the shutdown, ALS staff will be installing the COSMIC non-evaporable getter (NEG)-coated vacuum chamber and EPU insertion device. This will be the first major use of NEG coating in the ALS storage ring and represents an important step in developing experience with the NEG technology, which is essential for the ALS Upgrade Project (ALS-U).
ALS staff will also clear out the sector 2 straight to make way for the new GEMINI in-vacuum insertion device (IVID). Sector 2 of the ALS currently contains a number of components key to ALS operations. A multi-year effort to relocate these components to other areas of the accelerator has been under way. This year’s activities are phase two of three. During this phase, staff will be removing a decommissioned longitudinal RF kicker, which had its functionality replaced by a new component last shutdown. In addition, the pinger magnet system will be removed and set aside for re-installation during a future shutdown, the camshaft kicker will be removed and mothballed, and the third harmonic cavities will be moved from storage ring sector 2 to storage ring sector 3. This work will open the vacuum system, which requires significant vacuum conditioning and commissioning. The GEMINI IVID will be installed in a future shutdown.
Many other maintenance and upgrade efforts on the accelerator and beamlines will also be accomplished during this shutdown.