VERSAFLOW 4/55: Maximum flexibility with VERSAFLEX

The same variety seen in the KEBA product spectrum is reflected in the components and PCB panels in electronics manufacturing. This of course results in different spacing of the PCB in use.

In order to process these economically, a further stipulation made by KEBA was the automatic programme-controlled y-setting option for the axes in the double soldering module. In the course of the project, it became evident that it was not the standard double soldering module which achieved the best cycle times and flexibility but rather the individually-adjustable VERSAFLEX module. In this double soldering module, the two solder pots are not installed on one axis but rather on two independent axes. This gives KEBA completely new possibilities as regards the variability of the system – depending on the application, PCB panels can continue to be processed in parallel operation. For products which, for example, are processed using different nozzle diameters, the asynchronous mode is ideal. Here the two pots move on their axes completely independently and do their jobs at the same time which, of course, is positively reflected in the cycle time.

The CAD Assistent 4 integrated into the machinery software of the VERSAFLOW 4/55 is used for creating the soldering programmes. The auto routing function ensures optimised cycle times thanks to efficient process paths. Definition of the exclusion areas prevents collisions. In addition, the software automatically distributes the soldering tasks to the two existing modules and contributes further to optimised cycle time. “With the VERSAFLEX modules, we were able to give KEBA exactly the flexibility and efficiency which the company needs in the new selective line,” says Ersa Sales Manager Mark Birl. Nor does KEBA have to compromise in any way on soldering quality. Delivery was taken of the VERSAFLEX ULTRA software package which allows each soldering point to be assigned an individual set of parameters. “As a result, the customer does not have to work with average values, but can process each soldering point with the matching parameters,” explains Mark Birl further.

A European electronics manufacture  can only survive in international competition by supplying top product quality. When it comes to soldering, the soldering module alone is not decisive. The preliminary process too – such as pre-heating – plays a vital role. Homogenous and gentle pre-heating is important to avoid damaging the components. In order to guarantee reliable and good capillary fill, the right basic temperature of the PCB and component is necessary. In this way it is possible to avoid the liquid solder solidifying half way through the process, because the PCB or component draws off too much heat energy. The second risk is that the PCB or components suffer thermic shock as soon as it comes into contact with the solder. Excessive temperature differences can lead to mechanical tensions resulting in damage to the assembly.

The KEBA products are what are known as long lead time items – this means relatively long soldering times per product. This requires a good basic temperature for the assembly. “For this reason, we integrated an additional pre-heating module in front of soldering module 01, and a additional pre-heating module between soldering module 01 and 02 to retain the temperature of the assembly,” explains Mark Birl. Adaptations of this kind to meet specific customer requirements can be easily catered to thanks to the modular construction of the VERSAFLOW 4/55.

All pre-heating modules are equipped with IR lower heaters and upper convection heaters, guaranteeing efficient, reliable and homogenous warming. In addition, to further support the soldering process, heating was integrated into the nitrogen fumigation. The warm nitrogen exits the fumigation ring, surrounds the soldering nozzle and flows directly to the stele to be soldered. The soldering point is additionally heated to prevent premature hardening in the feedthrough. An advantage with slender pins, standing far apart, where the energy does not wander from soldering point to soldering point.

In the medium term, the VERSAFLOW will be working at full capacity in two-shift operation, because, at KEBA, all the signs indicate further growth. With the VERSAFLOW 4/55, the selective soldering area is ready to cope. And should a third soldering module become necessary, which KEBA anticipates – no problem either. Because the lines for energy and data transfer to the third soldering module have already been integrated into the machine. If expansion is required, a call to system partner Ersa is all it takes, and the system is upgraded and ready to go again in two days.