Facility to coat the SPS magnets with carbon

Objective: coat at least 90% of the SPS with a carbon thin film with low secondary electron emission in order to mitigate electron cloud.

Objects to coat: dipoles (MBB+MBA = 70%), Quadrupoles (QD+QF = 10%), LSS (10%), eventually SSS (10%). The pumping port shields shall also be coated.

Facility to coat the SPS magnets with carbon

Objective: coat at least 90% of the SPS with a carbon thin film with low secondary electron emission in order to mitigate electron cloud.

Objects to coat: dipoles (MBB+MBA = 70%), Quadrupoles (QD+QF = 10%), LSS (10%), eventually SSS (10%). The pumping port shields shall also be coated.

Quadrupoles , drift tubes for LSS and SSS, and pumping port shields will be coated in actual facility (b. 181-R-F12) (potential conflicts with NEG coating for LHC have not yet been analyzed)

Surface cleaning is mandatory prior to coat. Two options: 1) wet cleaning; 2) plasma cleaning (validation foreseen for 2014).

Facility to coat the SPS magnets with carbon

Surface requirements: 600 m2 (+100m2 for storage); >18 tons crane. Close to BA3 or BA5. (avoid road transport and easy extraction from tunnel )

Production constrains: ~1000 magnets to be cleaned and coated in one year (LS2) => 6 / day.

Coating systems required to assure such pace: 1) if wet cleaning 12; 2) if plasma cleaning 16. (two dipoles piled up per coating system).

Production steps for each dipole:

TE-VSC

Surfacecleaning coatingDismount

from SPS transport tocoating lab

TE-MSC

TransportTo SPS installation

TE-MSC

WET CLEANING PLASMA CLEANING

Surface required 600 (+100) m2 600 (+100) m2

Manpower 2 + 3 + 1 4 + 1

Advantages •Is Independent of coating systems

•Less handling of dipoles•The same people for cleaning and coating;

Disadvantages •Handling of radioactive liquids (0.5 Ton / dipole);•Install “demineralized” water circuit.

•Requires more coating systems

Wet vs Plasma cleaning

Coating system

16 meter

Dipoles pilled up by two

Pumping system + gas injection+ plasma generator + step motor

Structure to support graphite cathodeAnd stainless steel anode (in case of plasma cleaning)

16 coating systems in parallel

32 meter

19 meter

The prototype coating system (b.181-R-G12)

The prototype coating system (b.181-R-G12)

The prototype coating system (b.181-R-G12)