Vision_Series_EN - 第16页
16 Parallel processes Lead-free and leaded soldering in one system Do you want to run two different processes alongside one another in the same reow system while ensuring thermally sensitive circuit board assembly on to…
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Opened vacuum chamber of the VisionXP+ Vac
Divided, separately regulated transport system
The VisionXP+ Vac has a tripartite transport system:
pre-heating/peak area, vacuum unit and cooling zone.
All three areas of the transport system can be optionally
equipped with a central support for particularly wide boards.
The possibility of reducing the transportation speed in the
cooling zone when using the vacuum enables the extension
of the cooling time of components and therefore guarantees
an optimum temperature for subsequent process steps. The
throughput of the system is additionally increased with the
expansion of the transport system by a second track.
The vacuum chamber is installed in the VisionXP+ Vac as
an enhancement to the available peak zones. The integrated
pyrolysis and separate ltering of the atmosphere extracted
from the vacuum chamber are additional plus points in terms
of maintenance and cleaning. A generously dimensioned
vertical travel range of the vacuum chamber in the service
position enables good access to the internal mechanisms
during maintenance periods.The automatic running of the
process chamber into the processing or maintenance posi-
tions minimises downtimes and reduces maintenance effort.
All heating zones of the VisionXP+ Vac are regulated indi-
vidually and separated from each other thermally, guaran-
teeing flexible prole guidance and a stable reflow process.
The measurement of a temperature prole with the vacuum
process switched on shows that despite a very low vacuum
of 10 mbar, all prole settings have been fullled (≤ 3 K/s
heating, tL ≤ 90 s, TP ≤ 240 °C). With the help of the heating
integrated into the chamber, the temperature of the compo-
nents inside the vacuum unit can be adapted to the settings
of the most common standards. This rened solution
ensures a time-efcient and stable production process.
Efcient, easy to maintain and void-free
Precise pressure and temperature proling
VXP+
Vac
VXP+
Vac
VXP+
Vac
Pressure and temperature prole of a soldering process with the VisionXP+ Vac
without vacuum with vacuum
VisionX-Series | Vacuum
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Parallel processes
Lead-free and leaded soldering in one system
Do you want to run two different processes alongside one
another in the same reow system while ensuring thermally
sensitive circuit board assembly on top of this? In that case
you will need a great deal of exibility when it comes to
parameter setting. The technical conguration of the dou-
ble-track model from the VisionX-Series enables incredibly
exible process set-ups, thus opening up a wide working
window for soldering. The double-track systems are tted
with two transport tracks which can be asynchronously
operated at varying speeds.
Heating zones which are well thermally isolated from one
another, positioned in a grid of 350 mm both above and
underneath the transport tracks along the length of the
process chamber enable a wide range of reflow proles.
Just one homogeneous heating zone with one dedicated
fan stretches across the width of the process chamber
and both transport tracks in each case. There are abso-
lutely zero thermal barriers between the transport tracks
(gas baffle plate) or split nozzle arrays that could individ-
ually influence the gas flow on the right and left transport
tracks, meaning that the temperature and speed of the
gas flowing on both tracks are the same. If the two tracks
have both leaded and lead-free components mounted,
optimum reflow proles can be achieved by means of
different transport speeds. The VisionX-Series offers the
best conditions for this.
Pb
Pb
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In the SSP (Speed Switch Process) the process atmosphere
cooling process takes place without impacting the nitrogen
level. Extra pipes are installed in the pre-heating and peak
zones to serve as an outlet through which the cooler ambi-
ent air can be drawn by the internal exhaust system and a
fan upon activation of the SSP, serving to achieve the zones'
target temperature. Quick exhaust is activated when there
is a change of program to a lower temperature prole and
is deactivated once the temperature tolerances have been
reached.
SSP
SSP+
The SSP+ functions according to the same principle as
the SSP in the case of a process change, but an additional
setting possibility distinguishes it from SSP. When it comes
to proles with high temperature differences between the
individual heating zones SSP+ can be used to achieve an op-
timum division of zones. Because temperature can overspill
from a zone with a high temperature into neighbor zones, it
may be necessary to actively cool this on a permanent basis
in order to ensure the relevant temperature prole. Here
the internal exhaust system draws the colder ambient air
through correspondingly installed pipes and, in doing so, en-
sures precision temperature stability in the respective zone.
The spill-over heat from neighbor zones is thus drastically
reduced and optimum zone division guaranteed.
VXP+
Vac
VXP+
Quick Exhaust
Quick exhaust serves to extract process atmosphere rapidly
as a means of achieving the desired temperature change.
Here the process gas in the cooling line is extracted via the in-
ternal exhaust system. Quick exhaust is automatically activat-
ed if there is a change of program to a colder prole. As soon
as the temperature is within the tolerance range specied by
the program, quick exhaust is automatically deactivated.
VXP+
Vac
VXP+ VXS
VXS
Optimised process changeover
Rapid switch to lower temperature proles
Process changes often need to take place during a production shift, where the reow soldering
system requires longer periods to cool from a higher to a lower temperature prole. This is the case
for example when changing from lead-free to leaded solders. For considerably quicker cooling Rehm
offers various options which enable drastic reductions in waiting times.
VisionX-Series | Process changeover