Search NASA⌕ Search

Engineering topics

Rabehl, R.

Publications and source records attributed to Rabehl, R..

AUP First Pre-Series Cryo-Assembly Design Production and Test Overview

New high field and large-aperture quadrupole magnets for the low-beta inner triplets (Q1, Q2, Q3) have been built and tested as part of the high-luminosity upgrade of the Large Hadron Collider (HL-LHC). These new quadrupole magnets are based on Nb3Sn superconducting technology. The US Accelerator Upgrade Project (US-AUP) is producing the Q1 and Q3 Cryo-Assemblies: a pair of ~5 m long magnet structures installed in a stainless-steel helium vessel (Cold Mass) and surrounded by cryostat shields, piping, and a vacuum vessel. In conclusion, this paper gives an overview of the design, production, and the results of the horizontal test of the first pre-series Q1/Q3 Cryo-Assembly.

43 PARTICLE ACCELERATORS↗

Quench Performance of the First Pre-series AUP Cryo-assembly

The High Luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN will include eight cryo-assemblies that are expected to be fabricated and delivered to CERN by the US HL-LHC Accelerator Upgrade Project (AUP) as part of the U.S. contributions to the HL-LHC. These cryostat assemblies are the quadrupole magnetic components of the HL-LHC Q1 and Q3 inner triplet optical elements in front of the two interaction points. Each cryo-assembly consists of two 4.2 m long Nb 3 Sn quadrupole magnets with aperture 150 mm and operating gradient 132.6 T/m. The first pre-series cryo-assembly has been fabricated and successfully tested at the horizontal test facility at Fermi National Accelerator Laboratory. Here in this manuscript we report the quench test results of the LQXFA/B-01 cryo-assembly. The primary objective of the horizontal test is full cryo-assembly qualification and validation of the performance requirements.

43 PARTICLE ACCELERATORS↗

Fermilab's Horizontal Test Stand Upgrade Overview and Commissioning

Cryo-assemblies with the Nb 3 Sn MQXFA low-beta quadrupoles for the High Luminosity LHC (HL-LHC) upgrade will be tested at Fermilab's magnet test facility. A total of 10 cryo-assemblies will be delivered to CERN within the US HL-LHC Accelerator Upgrade Project (AUP). The horizontal test stand at Fermilab already has been used for testing the existing LHC inner-triplet quadrupoles, but the stand and corresponding electrical and cryogenic sub-systems were not operational for more than a decade. In order to restore the test stand functions and meet the design and test requirements for the HL-LHC magnets, the existing horizontal test facility at Fermilab underwent a significant refurbishment of the cryogenic and mechanical components. Most of the upgrades were completed and verified during so called zero-magnet test by late 2020, and then final commissioning of the upgraded horizontal test stand was completed during the first cryo-assembly test in 2023. These tests verified the major cryo-mechanical installations, as well as the basic test stand operations, including controlled cooldown and operation at 1.9 K, magnet protection and process controls. Here, in this paper, overview of the Fermilab's horizontal test facility upgrade and commissioning of these upgrades are presented.

43 PARTICLE ACCELERATORS↗

Fermilab’s horizontal test stand upgrade overview and commissioning

Cryo-assemblies with the low-beta Nb3Sn quadrupoles for the High Luminosity LHC (HL-LHC) upgrade will be tested at Fermilab’s magnet test facility. Total of 10 cryo-assemblies will be delivered to CERN within the US HL-LHC Accelerator Upgrade Project (AUP). The horizontal test stand at Fermilab already has been used for testing the existing LHC inner-triplet quadrupoles, but the stand and corresponding electrical and cryogenic sub-systems were not operational more than a decade. In order to restore the test stand functions and meet the design and test requirements for the high luminosity LHC magnets, the existing horizontal test facility at Fermilab underwent a significant refurbishment of the cryogenic and mechanical components. Most of the upgrades were completed and verified during so called zero-magnet test by late 2020, and then final commissioning of the upgraded test stand was completed during the first cryo-assembly test in 2023. These tests verified all the cryo-mechanical installations, as well as the test stand operations, including controlled cooldown and operation at 1.9 K, the helium recovery capabilities, magnet protection and process controls.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

AUP first Pre-Series Cold Mass Installation into the Cryostat

For the HiLumi LHC Upgrade (HL-LHC), new high field and large-aperture quadrupole magnets for the low-beta inner triplets (Q1, Q2, Q3) are being built. These new quadrupole magnets are based on Nb3Sn superconducting technology. As part of the US-HiLumi Accelerator Upgrade Project (AUP), ten Cryostat Assemblies (LQXFA) for Q1 and Q3 replacement will be built, tested, and delivered to CERN. The first LQXFA was assembled and tested at Fermi National Accelerator Laboratory (FNAL) during fall 2022 and spring/summer 2023, respectively. This paper summarizes the assembly process and experience of the first LQXFA Cryostat Assembly at FNAL.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

AUP first Pre-series Cold Mass Installation into the Cryostat

For the Hi-Lumi LHC Upgrade (HL-LHC) new high field and large-aperture quadrupole magnets for the low-beta inner triplets (Q1, Q2, Q3) are being built. These new quadrupole magnets are based on Nb3Sn superconducting technology. As part of the US-HiLumi Accelerator Upgrade Project (AUP) ten Cryostat Assemblies (LQXFA) for Q1 and Q3 replacement will be built, tested and delivered to CERN. The first of the LQXFA was assembled and tested at Fermi National Accelerator Laboratory (FNAL) during the fall of 2022 and spring 2023. We will present the integration work of the Cold Mass assembly into the Cryostat Kit provided by CERN. Each Cold Mass contains two trained MQXFA magnets of ~ 5 m length installed in a stainless-steel helium pressure vessel. The Cold Mass will be surrounded by cryostat shields, piping, and vacuum vessel. We will discuss the metrology survey results and present the LQXFA measurements prior testing at the Fermilab Magnet Test facility and lessons learned.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

C1Po2D-04: Cryogenic Testing of the First HL-LHC Q1/Q3 Cryo-Assembly at

In early 2023, Fermilab is conducting horizontal cryogenic testing of the first Q1/Q3 Cryo-Assembly for the high-luminosity LHC upgrade (HL-LHC). The Cryo-Assembly was installed on the upgraded Fermilab horizontal test stand previously used for testing the LHC inner triplet quadrupoles. The cryogenic process requirements of this test include controlled cool-down and warm-up with a 100 K maximum temperature differential between the two ends of the cold mass, operation of a 1.3 bar, 1.9 K bath of subcooled superfluid helium during power testing and magnetic measurements, and operation at pressure up to 18 bar with full helium recovery after a quench.

Rabehl, R.↗

Cryogenic testing of the first HL-LHC Q1/Q3 cryo-assembly at Fermilab

In early 2023, Fermilab is conducting horizontal cryogenic testing of the first Q1/Q3 cryo-assembly for the high-luminosity LHC upgrade (HL-LHC). The cryo-assembly was installed on the upgraded Fermilab horizontal test stand previously used for testing the LHC inner triplet quadrupoles. The cryogenic process requirements of this test include controlled cool-down and warm-up with a 100 K maximum temperature differential between the two ends of the cold mass, operation of a 1.3 bar, 1.9 K bath of subcooled superfluid helium during power testing and magnetic measurements, and operation at pressure up to 18 bar with full helium recovery after a quench. This paper presents the operational experience gained from this first test.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Design of the Fermilab Pre-Series Cold Mass for the HL-LHC Accelerator Upgrade Project

Here as part of the U.S. contribution to the HL-LHC Accelerator Upgrade Project (AUP), Fermilab is designing and building cold masses suitable for use in the LHC interaction regions. The cold mass provides a vacuum-tight helium enclosure for the magnets. Two magnets are aligned both axially and in cross section at Fermilab based on survey and warm magnetic measurements. Bus work and instrumentation is added. A welded stainless steel vacuum-tight shell surrounds the two magnets, and the structure is prepared for insertion into the cryostat. This paper summarizes the design of the cold mass including alignment, bus work, weld details, and instrumentation.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

U.S. HL-LHC Accelerator Upgrade Project: Q1/Q3 Cryostat Assembly and Horizontal Test (Final Design Report)

The Inner Triplet (IT) quadrupoles are the magnetic system for reaching low beta functions around the Interaction Point (IP). The triplet is made of three optical elements: Q1, Q2, and Q3. The upgrade of the Inner Triplets in the high luminosity insertions is the cornerstone of the LHC upgrade. The decision for HL-LHC heavily relies on the success of the advanced Nb 3 Sn technology that provides access to magnetic fields well beyond 9 T, allowing the maximization of the aperture of the IT quadrupoles. A 15-year-long study led by the DOE in the US under the auspices of the U.S. LARP program, and lately by other EU programs, has shown the feasibility of Nb 3 Sn accelerator magnets. The HL-LHC is expected to be the first application of accelerator-quality Nb 3 Sn magnet technology in an operating particle accelerator.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗