Decay Tube & Windows
Introduction(Location, Planning)

Decay Tube
Entrance Window
Exit Window
Vacuum System
11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons

1

Location

Decay tube
SleevesStore
Exit Window

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons2

Location

Install
FlangeInstall
Pumps
Decay tube

InstallExit Window

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons

3

Location

Install
Entrance
Window

Pumps
Decay tube

Exit Window

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons

4Planning

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons2006

11/11/2003

2005

JanuaryVent Decay Tube
Install Entrance
Window & Flanges
Bring back to vacuum

2004

AugustInstall Vacuum Pumps
Install Exit Window
Install Temporary Entrance Flange
Bring Decay Tube to Vacuum

2003

October
Transport Exit Window& Storage in Hadron Stop
Install Decay Tube (November 2003 -May 2004)5

Decay Tube
Decay Tunnel:
Internal diameter of 3.5m, 992m long, slope of 5.6%
Supported by shotcrete

Decay Tube:
Internal diameter of 2.45m, 998m long, 18mm thickMade of carbon steel
Vacuum 1 mbar

Decay Tube Sleeves:
6m long (2x3m, welded)
Will be combined to 18m long sleeves in target cavern

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons6Decay Tube: Transport
Transported from surface to target cavern

Mechanical workshop in target cavern
Top View
Æ To decay tube

3x6m sleeves welded Æ 18m
11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons7

Decay Tube

3 x 6m-sleeves on surface

11/11/2003

3 x 6m-sleeves in target chamber

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons

1x18m-sleeve in target chamber

8

Decay Tube: Installation
4 top supports
Lifting beam
4x10t jacks

3 fixed supports
winch

welded & checked

concrete

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons9Decay Tube: Quality ControlContractor - Independent Control Agency - CERN
Plates / Pipes
Dimensions, chemical analysis, mech. characteristics
Ultrasonic test
Welds
Visual Inspection
Ultrasonic test
Dye-Penetrant
X-RaysWorkshop *
100%
85%
100%
15%**

100%
20%

Decay Tunnel *
100%
100%
100%
---Tightness test of Decay tube - At the end of the works* %=percentage of weld length checked**X-rays check all welds not checked by ultrasound
11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons

10Entrance Window
Minimize particle loss Æ Thin

2mm Titanium window

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons

11Entrance Window: Safety
FE calculations Æ ok, no active cooling needed
X-ray & pressure test 3 bar Æ ok
Rupture?
Installation
Temporary Flange
Shut Down
Window + Shutter

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons

Safetyduring access(vent if doubt)12

Entrance Window: Safety
But what if rupture during beam?
SafetyPressure drop <0.5bar
Wind speed <<5m/s

FE-ModelNearestpersonRupture D=1.7m (full)Rupture D=0.5m
Reduced X-sections
Pits as buffer

1bar
1mbar

Results

Problem?

Pressure dropWindspeed

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons

2200Pa
200Pa
36m/s
10m/s

13

Entrance Window: Safety
Solution…

Sufficient?
Æ More calculations
Æ Other ideas
11/11/2003

Use ventilation to balance pressure(pressure losses in ducts)

Æ High-velocity zone moved
e.g. 2200Pa, allow 50m/s
Æ Duct of D=0.45m, takes 10 mins
NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons14

Exit Window Location

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons15

Exit Window
Lower energy particles Æ Thick

50mm Carbon Steel
Avoid high temperatures(beam dump: uncontrolled area, no access)FE calculations Æ not safe
(beam dump cooling: extra circuit easy to add)

Æ Active cooling
11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons16

Exit Window

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons17

Exit Window: Installation

Oct-03Aug-04
11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons18

Exit Window: Installation

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons

Oct-0319

Vacuum System

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons

20

Vacuum System
Vacuum Pumps
Pumps with air cooling or independent cooling circuit
Dry pumps Æ no oil Æ no duct needed for exhaust

Principle of Dry Pump

2 identical pumps of 250m3/h
Æ 3 days pumping to obtain 1mbar in decay tube

11/11/2003

NBI 2003 - Decay Tube and Windows
Presentation by Ans Pardons21