Technical_reference.pdf - 第98页
Technical Service Manual 98 Revision Dat e: August 2004 A IR M O DE- The N2 s olenoid and the Compr essed Air Solenoid will toggle, fo llowing the selection of an Air profile by the operator. All gas flows in the oven re…
Technical Service Manual 97 Revision Date: August 2004
FUNCTION OF THE FLUX EVACUATION SYSTEM
N2 Mode -
The Flux Flow Control Manifold creates a recirculation loop by drawing gas from the tunnel into the controlled exhaust
plenum between the last heat and first cool zones, and returning it to the preheat and soak zones through several of the
patented individual cell inlets. The force powering this recirculation loop is low pressure at the cell inlet, created by the cell
fan. There are no moving parts to this system.
Flow into the controlled exhaust plenum is biased in favor of drawing from the cool zone side. This is accomplished by
raising the pressure in the cool zone (by inputting a high percentage of the total oven nitrogen consumption into that
area), and by reducing the pressure in the last heated zone (by fully opening the individual cell outlet.) The total oven
exhaust is taken from this one port.
The recirculation loop carries low O2 PPM gas from the first cool zone, into the preheat and soak sections of the heated
zone, maintaining low O2 PPMs throughout the tunnel. The recirculation loop carries out flux contaminants trying to enter
the cooling zones. The higher pressure in the cooling zones inhibits the migration of flux contaminants from the heated
zones. The amount of flow into the controlled exhaust from the last heated zone is at a rate that will maintain the total
recirculation loop gas temperature above 120°C, which prevents condensation.
Exhaust flow out of the oven is maximized in volume, and also positioned in the tunnel at the point of highest flux
concentration (the last heated zone), to maximize the amount of flux contaminant per cubic foot of exhaust.
Technical Service Manual 98 Revision Date: August 2004
AIR MODE-
The N2 solenoid and the Compressed Air Solenoid will toggle, following the selection of an Air profile by the operator. All
gas flows in the oven remain identical to the N2 Mode, except that Nitrogen is replaced with compressed Air. Flow ratios
and all other process parameters remain identical.
MAINTENANCE
The Flux Flow Control system is virtually maintenance free if operating properly. To ensure this, it is recommended that
the inlet tube from the Flux Flow Control manifold into zone 1 be checked periodically (every six months) for flux residue.
The Flux-Flow Control System is located under the sheet metal skins at the top of the Oven:
Individual Zone Exhaust Duct
Flux Flow Control Duct
Technical Service Manual 99 Revision Date: August 2004
HOODLIFTS
) Standard, (installed on all ovens) ! An option, (NOT installed on all ovens)
Operation;
The electromechanical actuators raise and lower the Hood (including the upper heat zones of the oven). All models of
Vitronics-Soltec Reflow Ovens have 2 or 3 (depending on oven size) LINAK hoodlift Actuators with a LINAK control box
directly wired to the HOOD UP and HOOD DOWN selector switch on the oven operator control panel. The general
arrangement of the LINAK Actuators is shown here. A UPS option is available to permit opening the Oven Hood in the
event of a power failure.