Implementation of Light Weight Magnetic Shielding into the
LHC Ventilation Crates
Introduction
This note addresses the concerns regarding the light weight shielding expressed at the
LEAF meeting on 26 August 2005.
The conceptual design of these units was completed several years ago and agreed
upon among the concerned parties. In this design, the fan-motor would be shielded by
relatively heavy (mild-) steel shielding.
Since some time, a physicist, L. Periale, who works in the group PH-ESS, has done
some development and tests, with the motivation to find a solution with a shielding
material lighter than the one in the conceptual design.
It was agreed with C. Parkman that when those tests have delivered results which can
be considered conclusive, TS/LEA will explore how this can be engineered into the
crate.
Moreover, magnet experts are being consulted to review the solution before resources
are used to update the drawings and negotiations with the manufacturer are initiated.
Implementation of this improved shielding into the design of the unit should only be
done after engineering and tests have been completed successfully. In the mean time,
the heavy solution, which is known to not be very practical, remains the baseline.
Plan of work





Meeting with C. Parkman and L. Periale to transfer the results of their tests of
the lighter material shielding, and any other observations which need to be
taken into account when implementing this into the fan crate.
In the mean time, consultation with magnet experts should progress to review
the solution before further resources are used.
Update of the drawing (with the help of D. Gabriele who has done the original
drawings) which can be analyzed by the manufacturer of the crate (including
the shielding).
Fabricate a set of shielding and make a comparative test-run in the test magnet
which has been used for the previous units.
Upon conclusive tests, the units with plastic fan-turbines can be ordered with
this light weight shielding material. The contract with Automelec/Peruzzi must
be commercially adapted (negotiated) to this modified shielding (the heavy
shielding is included in the initial supply upon request)
Magnet Shielding Project Responsibilities:
PH-ESS
 Transfer of the proposal, test results and material data of the proposed
shielding.
TS/LEA
 Engineering of the implementation into the fan crates.
 Test-run of a fan-crate in the test magnet with comparison of the previous
results with the heavy shielding.
 Participate in the negotiation with the manufacturer for the fabrication of the
units equipped with shielding.
FI/LS
 Logistics concerning the units, which are stores objects.
 Interface with the experiments concerning their need related to volume and
time.
 Negotiations with the supplier.
Provisional schedule:
15 September: Drawings updated; contacts made with possible shielding
manufacturers.
1 October: Test shielding made, tests done and negotiation with the contractor
finalized.
15 October: Orders done for 100 units fully equipped with magnetic shielding.
30 November: Delivery of the 100 units (can be done in batches of 20).
M. Wilhelmsson
TS-LEA