Control Signals -» SMD Soldering

---

SMD Soldering

MODEL: SLR RANGE OF IR-REFLOW SOLDERING SYSTEMS

SLR Range of reflow soldering systems are the state-of-the-art soldering systems for SMD and hybrid PCB assemblies. SMD Components are soldered on the PCB by the reflow process: a process where desired amount of solder paste is applied to the PCB pads; SMD is gluded/placed on the pads and then this assembly is heated to a temperature slightly higher then the melting point of solder. The solder paste heats, melts and reflows forming a strong metallurgical joint. Heat is transfered to the PCB and SMD by rediation from a heat source that faces the PCB side to be soldered. Heat transfer by radiation is goverend by three parameters; Temperature of heat source, distance between the source (heater) and the sink (PCB) and the duration of expouser (inversely proportional to chain speed) All three parameters are infinitly controlable in this range of machines.

Short-wave-Iength Infra-Red Radiation, from the customised Quartz heater with parabolic metallic reflecting mirrors, serves as the uniformly diffused heat source for soldering of the highly dense SMD-PCB-asseniblies.

The system is suitable for soldering even fine print tracks upto 10 mils, without damage to the components and PCB of even FR-3/-FR-4, grade, laminates.

The system in-corporates three banks of diffused short-wave Infra-red heater assemblies, a motorised conveyor (Variable speed) and reverse black radiators.

An infinite number of heat/temperature profile to suit various density packing of SMDs are built into the system by incorporating an adjustable power source for the three heater banks.

The PCB assembly that enters the processing zone of the machine is first pre-heated to 110-140° C to activate the flux content of the solder paste and evaporation of the solvent and vehicle.

The mid-zone then reflows the solder at 200-2400C and the solder bond is established. The PCB assembly now enters the dwell and controlled cooling zone of heater banks where the temperature of the PCB assembly is gradually brought down to 100-120°C, avoding the thermal and mechanical stresses that might develop due to solidification of the solder and cooling of the PCB assembly.

The SMD-PCB-assembly then exits out of the processing zone on the chain-conveyor.

An 'induced-draft' exhaust hood is an integral part of the soldering system and is provided to remove flux vapours and fumes from the working zone, establish the convection heating pattern, and to aid the heat-up process inside the processing zone.

SPECIFICATIONS OF THE SYSTEM	SLR-6	SLR-12	SLR-14
Heating Zone width	150 mm	310 mm	360 mm
Max PCB Width that can be processed	140 mm	300 mm	350 mm
Power Requirement (IR Heat-zone)	8 Kw	10 Kw	12 Kw
Chain Conveyor	30 Watts	50 Watts	50 Watts
Supply Voltage (Three phase/ single phase)	230 VAC	230 VAC	230 VAC
LxWxH (mm)	18OO x 600 x 800	18OO x 800 x 800	18OO x 850 x 800