The CNGS Target Station

Technical Study
By theTarget Working Group

Presented by L.Bruno
AB/ATB

7-11 November 2003

Targets & Dumps Section

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

1

The CNGS Target Station

OUTLINE
1. Introduction
2. Shielding
3. Target Unit
4. Structural issues
5. Summary

7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

2

Introduction(that is, what I will say and what I will NOT…)

Subjects covered in previous workshops
9Driving parameters

9

Conceptual design philosophy

9Target configuration and optimization

Subjects covered in THIS workshop

7-11 November 2003¾

Engineering design of the shielding¾

Engineering design of the target¾

New issues and developments

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

3

Horn limit

Layout - Vertical view
Target enclosure
Crane limit

ShieldSteel frame

Target assemblyProton beam

Horiz. Base
plane

Fixed structure
7-11 November 2003

“Handled” structure

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

4

Layout - Front view

Iron shield

Passageside

7-11 November 2003

Side wall

Side wall

marbleTarget enclosure
800x1400x3200 mm3

CapCavernside
No accessProton beam

Base

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

5

Target handling
Fiducials

Beam

Unit
exchangemechanism

Alignment table

Collimator

Base table
BPKG
monitor

7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

6

Mobile shielding cap
ManualCoupling

Guidingrail

Passageside

7-11 November 2003

Quick
disconnect

Flat rail

Cavernside

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)7

Mobile shielding – Top view
MotorThreaded shafts

BPKG
Collimator

JacksSwitches

BeamRail sections
7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

Targetmagazine

Rail transition
8

Mobile shielding – Side view
Horizontal

Coupling

Slope 0.5%

Motor

B eam

7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

9

Target Alignment
Courtesy of D.Missiaen

Alignment is based on:

Passageside

Cavernside

No accessBase¾ 2 horizontal bars for : transversal alignment
 raw vertical alignment¾ 2 vertical back-up bars
used for accurate verticalalignment¾¾¾¾¾¾

Bars are:removable
equipped with fiducials
equipped with clinometer~1.2÷1.8 m longinclin. < 0.05/5 mrad (H/V)
provided with anhorizontalization system

Proton beam

7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

10

Alignment by the horizontal bars
Courtesy of D.Missiaen

Vertical measurements
performed by means of an optical level using a deepreference and/or the adjacent components. Accuracy
is not better than 0.15mm because of the barinclination.
Horizontal measurements
Done by a motorized tacheometer driven by a PC. The
operator is far from the area. Accuracy is in therange of 0.1 mm. The operator has to install and level
the bar in a radioactive area (short time).
PC-driventacheometer7-11 November 2003

Note: vertical measurements can be improved tobetter that 0.1 mm accuracy by using the verticalbars. Access to the radioactive top shielding is
restricted to long shut-downs
NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

11Target handling
Fiducials

BeamUnit
exchangemechanism

Alignment table

Collimator

Base table
BPKG
monitor

7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

12Target unit
The target unit is conceived as a static sealed systemfilled with inert gas. The tube has annular fins toenhance convective heat transfer.
Light materials are used to limit the heat load.

cad
En

Downstream
Window

Sealedfinned tube
InertgasdEn

artnCep
caubtleTarget Support

MATERIALS

Upstream
Window
7-11 November 2003p

Tube:
Windows:
Target Support:
Target rod:

Al-Mg alloy
Be by Brush & Wellman
Carbon Fiber reinforced Carbon
Fine-grain graphite
hexagonal boron nitride, CFC

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

13

Unit Windows
EB weld
B&W Bewindow(Ø1.5”)

Be-Al
joint
B&W Bewindow

Beam(Ø4”)

Aluminium
alloy 5083

St.Steel

7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

14

Upstream end cap“Pinch-off”
Helicoflex

Inner support

C-C Support Structure

7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

15

Central Tube
Outer
supportInner supports

A-A

7-11 November 2003

Outersupport

B-B

NBI 2003 – CNGS Target Station B-B
A-A
Presentation by L.Bruno (CERN AB/ATB)

Reference
surface16

Carbon Support Structure
Common ref.
surfaceTraversing
rod supports
7-11 November 2003

Inner supports
NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

Cooling
apertures17

Target elements – a new issue

New additional studies performed by an analyticalmodel point out that…

/////

If the target unit is cold (start-up)…
and a first proton spill of ultimate intensity…
hits the target with the worst misalignment…
followed by a second, similarly misaligned spill…
and stresses add up in the worst way ,Then…
7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)18

Maximum total stress [MPa]in a 2020PT graphite target rod… unacceptable stresses are found
7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

19

Target Material
hBNGraphite

52

3

σ4P

39

cp

26

21

E

13000200

400

600

800-11000

5σ4P

65

452α||E392

cp26

113α┴

00200

4006008000-11000

Temperature [°C]

Temperature [°C]7-11 November 2003

3α [µm/m °C]

4Young M. [GPa]65α [µm/m °C]

α/ σt [MPa]78

Cp [kJ/kg°C]5

Cp [kJ/kg°C]

Young M. [GPa]/ σt [MPa]78

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

20

Summary
Status in November 2003
1. The detailed design of the target station is being
worked out;
2. The choice of the alignment procedure is being
finalized;3. The target assembly is being optimized(manufacturing, integration,…)
4. The interfaces for handling, cooling, beam
instrumentation and alignment are being defined.
5. The worst-case stresses are presently an issue.
7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

21

Planning overview
2001

Technical study

Manufacturing

Installation
7-11 November 2003

Twg

2004

2005

Twg

2nd Review

Engineering study

Twg

1st Review

Conceptual design

2003

2002

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

22

Target element

7-11 November 2003

NBI 2003 – CNGS Target Station
Presentation by L.Bruno (CERN AB/ATB)

23