Dynamical Modelling Of The End-CAP Toroid Installation

Project Responsables:

from CERN: Marzio Nessi

from Center: Alexander Sharmazanashvili

Year : 2007

The End-Cap Toroid (ECT) is the heaviest individual assembly of the ATLAS detector, with a total mass of approximately 250 tonnes. Its installation requires lowering the assembly, together with its lifting fixtures, to a depth of 100 meters underground and positioning it with an accuracy of 50 mm. The installation sequence involves complex vertical and longitudinal movements while navigating through the highly congested environment formed by surrounding detector components.

Engineers from the CATIA Competence Center performed a comprehensive dynamic simulation of the installation process using detailed 3D models of both the End-Cap Toroid and the complete ATLAS detector. The analysis was carried out using the CATIA Digital Mock-Up (DMU) modules, and the results were documented in a detailed technical report.

The study concluded that the predefined installation trajectory for the End-Cap Toroid cannot be executed without significant modifications to several existing detector components. The required interventions are summarized below:

Muon Chambers

Removal of an interference (clash) at an elevation of 75.8 m (Point G, Segment #3). Elimination of a 71.0 mm clearance conflict at an elevation of 75.5 m (Point D, Segment #3).

Cryogenic Pipe

Elimination of a 74.5 mm clearance conflict at an elevation of 73.4 m (Point A, Segment #2).

The most critical section of the installation occurs between elevations of 75.6 m and 75.8 m, where extremely small clearances are observed on opposite sides of the End-Cap Toroid. The minimum available clearances are:

TX1S_Shielding: 33.4 mm (Point E, Segment #3). Service Pipe for the Muon Spectrometer: 33.0 mm (Point F, Segment #3).

These results demonstrate that the original lifting path is not feasible under the existing detector configuration and that the identified modifications are required to ensure the safe installation of the End-Cap Toroid.

Report:

.pdf 3.54Mb Installation:

.wmv 50.7Mb Simulated:

.wmv 64.7Mb