PIP-II Linac Cryogenic Distribution System Design Challenges

• Main Authors: Banaszkiewicz, T, Chorowski, M, Duda, P, Stanclik, M, Dhuley, R, Martinez, A, Soyars, W
• Format: Journal Article
• Language: English
• Published: 20-08-2024
• Subjects: Physics - Accelerator Physics
• DOI: 10.48550/arxiv.2408.11018

The PIP-II linac Cryogenic Distribution System (CDS) is characterized by
extremely small heat inflows and robust mechanical design. It consists of a
Distribution Valve Box (DVB), Intermediate Transfer Line, Tunnel Transfer Line,
comprising 25 Bayonet Cans, and ends with a Turnaround Can. Multiple helium
streams, each characterized by distinct helium parameters, flow through each of
these elements. The CDS geometry allows maintaining an acceptable pressure drop
for each helium stream, considering the planned flows and helium parameters in
different operation modes. This is particularly crucial for the return line of
helium vapors, which return from cryomodules to the cold compressors and thus
have very restrictive pressure drop requirements. On both sides of the DVB
there are fixed supports for process pipes. One of the DVB design challenges
was to route the process pipes in such a way that their shape provided
sufficient compensation for thermal shrinkage. This ensures th at the forces
resulting from thermal shrinkage acting on the cryogenic valves remain at a
level acceptable to the manufacturer. The required thermal budget of the CDS
was achieved by thermo-mechanical optimization of its components, like process
pipes fixed supports in Bayonet Cans.