Post on 18-Jan-2016
Muon Meeting 13/02/2004 LNF
G. Auriemma 2
• The first gluing machine is now in Potenza. • It is fully operational after the tuning by Federico and a lot of ------• The suction is not given by the Venturi tube, but by a vacuum pump
Muon Meeting 13/02/2004 LNF
G. Auriemma 3
Panels start flowing in…
3 panels picked-up 22nd Jan, next 7 arrived 10th Feb in Potenza
Muon Meeting 13/02/2004 LNF
G. Auriemma 4
Test of the machine• As a final check of the gluing machine the gluing of HV
bar on final panels has been performed, following the procedure seen during the visit to the LNF gluing laboratory.
• We tested the procedure on one copper-copper panel and one gold-copper panel, correctly cleaned with propanol (isopropylic alchool) and microfiber cloth.
• After the prescribed curing time the panel were removed from the machine and measured with a comparator. The precision of the gluing was found to be completely satisfactory.
• However 50% of the glued HV bar detached easily from the panels when simply pulled by hand
Muon Meeting 13/02/2004 LNF
G. Auriemma 5
Trace of failed gluing Cleaned with trichloroethylene
Copper -Copper panel #150
Muon Meeting 13/02/2004 LNF
G. Auriemma 6
Cleaned with trichloroethylene
Cleaned with propanolUncleaned
Gold-gold panel #208
Muon Meeting 13/02/2004 LNF
G. Auriemma 7
On the panel as it came from the factory there is a greasy substance that is
hydrophobic to ethanol
Muon Meeting 13/02/2004 LNF
G. Auriemma 9
Here the test is repeated on a portion cleaned with Trichloroethylen
Muon Meeting 13/02/2004 LNF
G. Auriemma 11
The grease was not present in the first batch that we received (copper-copper
panels #31 and #56)
On this panels the glue sticks extremely well even without any cleaning(see samples)
Muon Meeting 13/02/2004 LNF
G. Auriemma 12
Conclusions• It appears that something has been changed in
the forming of the panels, which should be investigated with the supplier
• The composition of this greasy layer should be understood in order to evaluate its impact on the performance of the chambers (specially for aging)
• In our opinion it is not guranteed that this substance is fully removed by cleaning with propanol
• From our tests to remove it strong organic solvents should be used (same experience at CERN where acetone is used)
Muon Meeting 13/02/2004 LNF
G. Auriemma 13
• Unfortunately we are not allowed by safety regulations to use toxic and flammable organic solvents in our lab due to insuffient ventilation, fire prevention and absence of specific drainage for chemicals.
• We think that if the use of this substance is required by the forming of the panels, it should be fully removed at the factory, before shipping, by cleaning the panels with acetone or trichloroethylen.