PIP2IT HEBT Final Design Review Vacuum design Alex CHEN In - - PowerPoint PPT Presentation

▶
pip2it hebt final design review
SMART_READER_LITE
LIVE PREVIEW

PIP2IT HEBT Final Design Review Vacuum design Alex CHEN In - - PowerPoint PPT Presentation

Feb 26, 2023 323 likes •544 views

PIP2IT HEBT Final Design Review Vacuum design Alex CHEN In partnership with: Final Design Review for the PIP-II Injector Test India/DAE Italy/INFN High Energy Beam Transport UK/STFC France/CEA/Irfu, CNRS/IN2P3 13 February 2019 2/13/2019

slide-1
SLIDE 1

In partnership with: India/DAE Italy/INFN UK/STFC France/CEA/Irfu, CNRS/IN2P3

Alex CHEN Final Design Review for the PIP-II Injector Test High Energy Beam Transport 13 February 2019

PIP2IT HEBT Final Design Review Vacuum design

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

1

slide-2
SLIDE 2

Outline

  • Introduction
  • Configuration
  • Ion Pumps
  • NEG
  • Cold Trap
  • Turbo Pump
  • MolFlow+ Simulation
  • Criterion for Optimization
  • Pressure Profile of residual gas (Hydrogen)
  • Vacuum Protection Test Results
  • Failure at Upstream of Differential Pumping Insert (DPI)
  • Failure at Downstream of DPI, (applied for HEBT)

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

2

slide-3
SLIDE 3

HEBT VACUUM

(Introduction)

  • Low Particulate Vacuum
  • 1E-9 torr at the entry of CM
  • Protect CM from vacuum failure

SSR1 HEBT Beam Dump and Shielding

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

3

slide-4
SLIDE 4

Configuration

  • Ion Pumps: to achieve UHV, HV for reliable operation, (4 vs 3)
  • NEG: in order to enhance hydrogen pumping at entrance of CM
  • Cold Trap: not chosen for cost/benefit reason
  • Turbo Pump: only for initial pumping down SSR1,
  • HEBT vacuum will be initially evacuated by slow pumping cart at

downstream port

  • Venting will be done through slow pumping cart from upstream port

near SSR1

  • One gate valve is used for segmentation

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

4

slide-5
SLIDE 5

HEBT VACUUM Configuration

(to SSR1 and Beam Dump)

Beam Dump and Shielding Ion Pump1 200 l/s w/ NEG Ion Pump2 200 l/s Ion Pump3 200l/s Ion Pump4 (optional) SSR1 GV NEG ( Capacitor Z400 by SAES) port capable to Pumping down/venting SSR1 Fast Close Valve Gate Valve

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

5

slide-6
SLIDE 6

SSR1-HEBT VACUUM Simulation

(Simplified Model in MolFlow+ )

2nd Half SSR1 Cavity String HEBT Dump 2.77E-6 mbar.L/s @Dump 2mA, 1.1% Hydrogen outgassing rate on all inner surfaces All 2.E-10 mbar.L/s.cm2 Ion Pumps 200 L/s CM: 2K, 0.99 Stick factor Transition: 2-5K (0.7) 5-50K(0.1) 50-300K, (0.0) LPM

(2.4E-7 mbar.l/s)

SLIT1

(4.6E-7 mbar.l/s)

F.C

(3.5E-7 mbar.l/s)

SLIT2

(4.6E-7 mbar.l/s)

F.C.

(3.5E-7 mbar.l/s)

Lg Tube

(2.2E-6 mbar.l/s)

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

6

slide-7
SLIDE 7

1.E-13 1.E-12 1.E-11 1.E-10 1.E-09 1.E-08 1.E-07

  • 100.0

0.0 100.0 200.0 300.0 400.0 500.0 600.0

Presure, mbar Distance From Gate Valve, cm

HEBT H2 Presure Profile Along Beam Line

F#3341, W-C F#3342, 1st C F#4665 HEBT1 F#4664 HEBT2 F#4557 DUMP

GV Pump Pump Pump Pump

SSR1-HEBT VACUUM Simulation

(Pressure Profile, Hydrogen)

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

7

slide-8
SLIDE 8

HEBT VACUUM (Warm Section)

(MolFlow Simulation: intermedium results)

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

8

slide-9
SLIDE 9

1.E-09 1.E-08 1.E-07 1.E-06 100 200 300 400 500 600

Pressure (mbar) Distance from Valve (cm)

HEBT H2 Pressure Profile

200-0-200 200-100-200 200-0-400 100-100-200 200-200-0 200-200-200

pump2 pump1

Ion Pump Size: 100 or 200 l/s

HEBT VACUUM (Warm Section)

(MolFlow Simulation)

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

9

pump3

  • Goal: to achieve 1E-9

Torr at the entrance of CM

  • Studied: the pump size

and its locations

slide-10
SLIDE 10

SSR1

(MolFlow Simulation)

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

10

pump3 Transition: 300K-50K-5K-2K

slide-11
SLIDE 11

1.E-08 1.E-07 1.E-06 1.E-05 1.E-04 1.E-03 10 20 30 40 50 60 70 80 90 100 Pressure (mbar) location

SSR1 Pumping Down

Air 6.5E-9 mbar.l/scm2 H2, 6.5E-9 mbar.l/s.cm2 H2 , 2.7E-10 mbar.l/s.cm2

SSR1

(Pumping Down with 160 l/s)

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

11

slide-12
SLIDE 12

2-5K (0.7) 5-50K (0.1) 50-300K (0.0)

SSR1-HEBT VACUUM Simulation

(Hydrogen Condensation on 1st Cavity surface)

Entire Cavity under 2K, 0.99 sticking factor, surface 8900cm2

  • The sticking factors of

hydrogen for the three transit region 2-5K, 5-50K, 50-300K are 0, 0.1, 0.7

  • Entire cavity was under 2K,

sticking factor 0.99 was assigned

  • Most significant hydrogen

flux arrived on the face of down stream wall

  • It takes 1.5 week to

buildup one monolayer on the face, however, on 1st cavity, H2 will diffuse on the other surfaces due to beam induced desorption

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

12

slide-13
SLIDE 13

SSR1-HEBT VACUUM Simulation

(Hydrogen Condensation on Cavity surface)

Facet # Sticking Opacity structur e area (cm2) Temp (K)

  • Imping. rate

(s-1m-2) Presure (mbar) Monolayer time, year even dist. Entire cavity Cavity4 67 0.99 1 5 125.085 2 2.72E+10 1.89E-15 1.32E+01 6.10E+02 777 0.99 1 5 125.085 2 1.46E+10 8.55E-17 2.45E+01 Cavity3 875 0.99 1 4 125.085 2 6.23E+10 4.29E-15 5.75E+00 3.50E+02 1585 0.99 1 4 125.085 2 1.06E+10 6.06E-17 3.39E+01 Cavity2 1683 0.99 1 3 125.085 2 1.44E+11 9.89E-15 2.50E+00 1.70E+02 2393 0.99 1 3 125.085 2 6.19E+09 3.61E-17 5.79E+01 Cavity1 2491 0.99 1 2 125.085 2 1.17E+13 3.43E-13 3.07E-02 2.18E+00 3200 0.99 1 2 125.085 2 2.67E+10 1.46E-16 1.34E+01

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

13

slide-14
SLIDE 14

Protection to CM from Vacuum Failure

  • Low particulate Vacuum practice in handling & installation
  • HEBT vacuum will be initially evacuated by slow pumping cart at downstream

port

  • Venting will be done through slow pumping cart from upstream port near

SSR1

  • One gate valve is used for segmentation
  • Fast close valve installed to minimize the vacuum failure impact on

CM

  • Test was done at MEBT,
  • Gas flux into CM is sufficiently low

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

14

slide-15
SLIDE 15

1st Test on MEBT DPI-FV

15

  • A. Chen | PIP2IT HEBT Final Design Review

M72WRP M61VSO M71S2P M63WRP M63DIP M11PIP M81VFC

LD PG Leaker Volume=0.29 liter

M72PIO M92WRP

1.

V1=36.5 liters(M61VSO-FV)

2.

V2=95.1 liters(POST FV)

3.

Permeation rate from Scanner O-Ring is about 6E- 7 torr.l/s

M52WRP

slide-16
SLIDE 16

Setup of 2nd Test

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

16

N2 Reservoir (0.33 Liter) Post FV Volume (2.79 liter) FV CC Gauge RGA Ion Pump Pirani Gauge

slide-17
SLIDE 17

2nd Test With Smaller and Tighter Volume (Leak From Downstream of DPI)

  • A. Chen | PIP2IT HEBT Final Design Review

17

With current setup

  • f DPI and IPs,

DPus/DPds =188 6.6E-6 7.6E-7 1.5E-8 4.6E-8 Pressure rise at US of DPI Pressure rise DS of PDI

slide-18
SLIDE 18

2nd Test With Smaller and Tighter Volume (Leak From Downstream of DPI)

  • A. Chen | PIP2IT HEBT Final Design Review

18

1.4E-5 with

Leaker at 350 Torr

4.5E-5 with

leaker at 810 Torr

1.0E-7 7.3E-9 3.8E-5 with

Leaker at 9.5 Torr

2.3E-8 Oct 1, 2-18

slide-19
SLIDE 19

Summary of Results for Vacuum Protection

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

19

1.E-07 1.E-06 1.E-05 1.E-04 1.E-03 1.E-02 100 200 300 400 500 600 700 800 900

Gas Amount Past (torr.l) Reservior Pressure (torr)

Gas Past Fast Valve in Vacuum Failures

UPSTREAM DOWNSTREAM

Leaker P0 P1 dP Gas Amount monolayer coverage Leaker Location torr torr torr torr torr.liter cm2 23-Aug 1.7 6.2E-09 1.7E-07 1.6E-07 4.6E-07 1.3E-02 US DPI 52 7.5E-09 1.9E-07 1.8E-07 5.1E-07 1.5E-02 24-Aug 760 7.9E-09 2.0E-07 1.9E-07 5.4E-07 1.6E-02 760 2.3E-08 2.3E-07 2.1E-07 5.8E-07 1.7E-02 1-Oct 9.5 7.3E-09 3.8E-05 3.8E-05 1.1E-04 3.1E+00 DS DPI 350 2.1E-08 1.4E-05 1.4E-05 3.9E-05 1.1E+00 810 1.0E-07 4.5E-05 4.5E-05 1.3E-04 3.6E+00 8-Oct 1.2 6.1E-09 5.1E-04 5.1E-04 1.4E-03 4.1E+01 9-Oct 130 6.0E-09 5.8E-07 5.7E-07 1.6E-06 4.6E-02 760 3.0E-08 2.5E-06 2.5E-06 6.9E-06 2.0E-01

slide-20
SLIDE 20
  • Configure can satisfy the vacuum requirement
  • MolFlow simulation was done, and residual gas (Hydrogen) pressure profile along

beamline was established,

  • However the hydrogen condensation on the cavity at ends may be a concern if no

sufficient desorption induced by beam or electrical power.

  • Fast valve to minimize gas flux into CM during vacuum failure
  • One gate valve to isolate the UHV region near CM from HV region near dump
  • All installation, pumping down, venting up follow practice of low particulate vacuum

Summary

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

20

slide-21
SLIDE 21

DPI (differential pumping insert)

2/13/2019

  • A. Chen | PIP2IT HEBT Final Design Review

21

Copper Tube 10mm(ID),200mm(Lon g) SS tube 1.5”(OD)

  • Al. cooling

Disc Ceramic Breaker (3kV) Ion Pump (100 l/s) Beam