BGV Chamber Concept and Layout

Ray Veness and Nicolas JuradoWith thanks to Plamen Hopchev and Giuseppe Bregliozzi

Chamber Concept

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• Main design constraints– ‘Window’ in thin-walled aluminium• AA2219 (6% Cu) is the only qualified grade that resists

NEG activation temperature and is weldable– Fits between the QRL and Beam 1 pipe– Has a realistic chance of manufacture for installation

at ~Easter 2014• Implies using materials already available at CERN and

standard solutions in critical locations

Chamber Concept

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A

B

C

D

Chamber Concept

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• A: Window chamber– Manufactured from AA2219 3D forged blocks

• 1 m long forged bars exist in VSC for 50 mm chamber section• 400 mm diameter block exists in VSC for window, but must be forged• Bi-metallic (Al-316LN) Conflat flanges (DN100 and DN 235) can be bought from ATLAS Technologies in

the USA

• B: Enlarged drift vacuum Chamber– Manufactured from stainless steel

• DN235/OD295 316LN flanges are CERN stores standard• 212/219 ID/OD tube (any length upto ~6.5 m) is a standard LHC vacuum chamber dimension – VSC

should have in stock• Vacuum chambers supports for this tube should also exist in VSC• Weld-in port(s) for gas injection if needed

• C: Transition Chamber– Could use ‘standard’ LHC transition from 212-80 mm with smaller flange– If smaller than 80 mm needed, then either use an insert or a special design

• D: Vacuum pumping modules– Standard 400 l/s ion pump modules, as defined by G.Bregliozzi

Chamber Concept

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OD295 flange gives only a 4.5mm clearance to the nominal OD of the adjacent beamline. This needs to be agreed with VSC

Preliminary Layout

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G.Bregliozzi proposes making new vacuum sectors, splitting A7L4 into A7L4, B7L4, C7L4 with 2 new valve/instrument sections and replacing 3x standard 7 m chambers with the BGV sector

New valves/instruments in these locations

Preliminary Layout

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According to this preliminary study by N.Jurado (BE-BI) the nominal position at ~DCUM 9775 should not interfere with QRL bellows or other equipment

Conclusions and Actions

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• Conclusions– A conceptual design has been proposed, using available materials for

critical parts, that could (with effort) be made within the LS1 timescale– A preliminary discussion with Plamen and Giuseppe has led to a layout

plan that appears acceptable for VSC and appears to fit in the LHC

• Next actions– Request approval from VSC for use of their materials (aluminium, stainless

tubes, supports) and for the 4.5 mm clearance to the adjacent chamber– Order long lead-time items: Forging of the OD400 aluminium block to a

rough shape; bi-metallic flanges– Request an ‘official’ integration study– Detailed design of the window chamber and the length of the drift

chamber can be studied in parallel with these actions