1. STT gas system a possible implementation
PANDA Tracking Meeting
October the 10th 2013
Jülich
STT gas system
a possible implementation
Guidelines adopeted to flush the PANDA straws
Parameters to be controlled
The gas flow piping: a possible realization with manifolds
Test of gas sealing on prototype manifold
Conclusions and open questions
V. Lucherini – INFN LNF

2. Setting the Task
To flux a mixture of gases, Argon-C02, 10(20)-90(80), through » 4650 straw tubes, assuring a given number (» 4 ) of gas changes per day in their overal volume (of » 1000 l) .
To ensure the required overpressure (» 2 bar), purity grade and sealing of the mixture.
To reduce the redundancy of the system to lower the costs, the material budget and the complexity.
To ensure a minimal redundancy to guaranty, in case of failure of single components, the operation of at least parts of any sector;
Full automated setting and remote control, with the possibility to switch to manual/local operation, of the gas flow parameters as:
- ratio of the two components in the gas mixture;
- quantifying the Inlet / Outlet gas flow;
- setting and controlling the gas over pressure;
controlling the temperature;
(uninterrupted gas flow).

3. Layout Control System (M. Bragadireanu talk)
Settling the Task
Build independent pipe lines, arranged in such a way to ensure an independent gas flux in every sector and in each main subdivision of each sector.
- one line per sector for each (inner & outer) axial straw regions: 6×2 = 12 lines;
– two lines per sector for each of the stereo straw groups: 6 × 2 = 12 lines.
Total: 24 pipe lines ( + 24 return pipes).
SST gas flux
Layout Control System (M. Bragadireanu talk)

4. STT (Straw Tubes Tracker ) &“Service Support Frame”
-Gas Pipes” lines: n.4
-Gas Pipes” lines: n.4
-Total “Gas Pipes” lines: 12
(For left half-tracker)
-Gas Pipes” lines: n.4
Gas Distribution
to straws on this side
- STRAW TUBE TRACKER
- SERVICE SUPPORT FRAME
-Gas Pipes” lines: n.4 p
-Gas Pipes” lines: n.4
straw-to-straw
gas piping on this side
-Gas Pipes” lines: n.4
-Total “Gas Pipes” lines: n. 12
(For left half-tracker)
1000 mm

5. PATHWAYS OF GAS PIPES (and HV cables)
-The encumbrance of the
connectors has not been
considered!
20 HV Cables
4 Gas Pipes
(From the Forward Side)
HV CABLE DATA
- Cross Section 8,1mm^2/each
- Total: 8,1x20 = 162mm^2 (Each Pathway)
- Weight: 0,0162 Kg/m
13 HV Cables
8 Gas Pipes
(From the Forward Side) 13 7
Theoretical needed cross section for each
top & bottom pathway: = 502mm^2
13 HV Cables 6
8 Gas Pipes
(From the Forward Side) 13
GAS PIPE DATA
13 HV Cables
- Cross Section 28,26mm^2/each
- Total: 28,26x12 = 340mm^2 (Each Pathway)
- Weight: kg/m
4Gas Pipes
(From the Forward Side)
12 Gas Pipes
20 HV Cables
Backward side

6. - GAS PIPES -
Weight: 0,0162Kg/m
Outer diam: 6 mm
Inner diam: 4 mm
Inox pipes to distribute (recover) the gas flow to individual straws

7. p GAS MANIFOLD SYSTEM Bleu pipes: gas inlet Yellow pipes: gas outlet
- STRAW TRACKER GAS SYSYTEM INTEGRATION. p
GAS PIPES GUIDE
FLUX TO INDIVIAL STRAWS
STRAW MODULES
SUPPORT END-PLATE
GAS MANIFOLD SYSTEM
Bleu pipes: gas inlet
Yellow pipes: gas outlet

8. Manifold for the Inner Layer
Bleu pipes: gas inlet
Yellow pipes: gas outlet

9. Manifold for the Skewed Layer
Bleu pipes: gas inlet
Yellow pipes: gas outlet

10. Manifod for the Outer Layer
Bleu pipes: gas inlet
Yellow pipes: gas outlet

11. Enlarged view of some of the Manifolds
Bleu pipes: gas inlet
Yellow pipes: gas outlet

12. Forward side: pictorial view of the manifols for one sector: three for each one
Bleu pipes: gas inlet
Yellow pipes: gas outlet

13. Forward side: pictorial view of the manifols for one sector: three for each one
Bleu pipes: gas inlet
Yellow pipes: gas outlet

14. Manifold encumbrance p
I.P.
1060mm
1142mm

15. Manifold prototype and test
No gas leakeage from the prototype (made in plexiglas) in a fist test lasting four days

16. Conclusions and open questions
A piping system to flux the SST hase been devised trying to follow the the guidelines of the SST TDR.
A compact network of pipes, distributed in an appropriate way in the external surface of the SST set-up can allow to bring the inlet and outlet gas flow in a compact way
A manifold has been devised as a possible “interface” between the inlet/outlet gas pipes and the distributor of the gas mixture to the individual straws
A propotype manifold has been realized and succesfully tested for gas sealing
…of course this is just one, between many, of the possibile solutions of the task...