1. Current Design and Short Status
ATF2 Collimator - Mechanics at LAL
Current Design and Short Status
I-LINK meeting 2015
LAL-IN2P3-CNRS and Paris-Sud Orsay University - Sandry WALLON – 01 July 2015 1

2. Outline « First » mechanical design (SS) : short brief
Alternative design in aluminum alloy : purpose ; pros and cons
Chassis for collimator
Manufacture, Checkings (vacuum, dimensions), mounting, Installation

3. 1. « First » mechanical design (SS) : short brief
Vacuum chamber (SS)
Indium wire seal (copper gasket possible [SS chamber])
DN40CF Flange (copper gasket)
848 mm
Transition foil (elastic part)
Transition pipe
Front wall
Linear slide
Jaw (mask)
600 mm
Backing plate

4. Transition foil (elastic part)
Rail (slide)
Transition foil (elastic part)
Front wall
Rear wall
Bellow
Stem holder
Carriage driven by ball-screw
Rated linear slides disp. repeatability : mm
Stem with brazed flange

5. 2. Alternative design in aluminum alloy : purpose ; pros and cons
Vacuum chamber (Al alloy)
Transition pipe
(inside vacuum zone ; screwed to chamber)
DN40CF Flange (SS) (screw to chamber ; indium wire crushed for tightness)
Purpose of Al alloy
Low production time to match LAL’s workshop work load Indium wire seal
Smaller design (height) required by rail length issue

6. Pros : Production on time at LAL
Lighter design (Chamber with its flanges : 15  7 kg)
No welds
Higher thermal conductivity
Cons :
Indium creeping (not worse than SS design) especially if beam hits entrance flange (but heat loss at very low level – see CST Nuria’s calculations [beam hitting the jaws])

7. Tansition part shift (SS/Al) : 30.7-5.3 mm

8. 3. Chassis for collimator : open discussion
Use of standard beam (Bosch system, …) : « building block style » Footprint to groung required, and way to fix the chassis (drawing from KEK)

9. 4. Manufacture, Checkings (vacuum, dimensions), Mounting, Installation
Main components already ordered (linear slides, bellows)
Production at LAL’s workshop expected to start on Aug.
Chassis to design and beams to order
Checkings foreseen (and to be planned) at LAL Vacuum leak - outgasing ; 3D (dimensions, geometrical specs)
Mounting ; checking jaws position / beam axis
Installation goal : Nov. or Dec. 2015