Even more agility for the EMS service provider from Erfurt

In 2017 Ertron had to purchase spare parts for its existing wave soldering system. The plant was getting a bit long in the tooth and reaching its technical limits. Preparation and post-treatment of assemblies, such as the masking of components that must not come into contact with solder, or the elimination of solder bridges after soldering was binding more and more capacities. This was also true of cleaning the assemblies, since the wave soldering system was equipped with a foam fluxer. Thomas Wohlgemuth (then responsible for the wave soldering department) brought back valuable impulses and ideas from his visit to the Ersa know-how seminar “Wave and selective soldering”. It was thus logical for Ertron that Ersa should also be included in supplier selection for the new soldering system and a corresponding inquiry was sent to Mark Birl, the Ersa sales engineer responsible. The only possible solution for Ertron was a full tunnel wave soldering system, because the main objective – apart from the economic factor – was long-term improvement of soldering quality. During the first talks it became apparent that on account of the Erton range of components and products, a selective soldering system could be the better choice rather than the POWERFLOW N2 wave soldering plant originally planned. During a visit to the Ersa Application Centre in Wertheim, Mr Probandt and Mr Wohlgemuth from Erfurt took a close look at both machine options. After the visit, the decision was clear: VERSAFLOW 4/55 with double soldering module was the right choice. The selective soldering system turned out to be the better solution for the products manufactured by Erton, and it scored in terms of flexibility and the soldering quality achieved during the tests.

Thanks to the new selective soldering system, time-consuming preparatory work that would have been necessary for the wave soldering process due to the Ertron product spectrum is no longer required. Unlike in the selective soldering process, the assembly moves in a fixed direction – the direction of travel – over the soldering wave in the wave soldering machine. The soldering wave comes into contact with the entire underside of the PCB in this case. Areas and components that must not be wetted with solder are either covered using special soldering masks or masked as at Ertron. In a selective system, on the other hand, only the components to be soldered are approached and processed by the soldering nozzle. As an additional benefit, this reduces the thermal stress for the assembly and has a positive effect on its quality. The setting possibilities are also limited with a wave soldering machine, this affects the holding time of the assembly above the soldering wave or the soldering wave tear-off, for example. The soldering program always has to use mean values. In the VERSAFLOW 4/55 on the other hand, soldering parameters can be entered individually for each soldering spot. Ertron regularly had problems with bridges formed between component pins during the wave soldering process, because connector strips had to be routed across the soldering wave due to the PCB layout. Missing or insufficient solder passages were also an issue.

Long-term improvement has been achieved with the VERSAFLOW 4/55 because all the soldering parameters including the nozzle to be used for each soldering spot can be defined individually and saved in the soldering program. The user uses PCB data, either CAD data such as DXF or ODB++, or graphic files such as GIF or JPG to prepare the soldering program with the CAD Assistant 4 – the program editor from Ersa that has been integrated in the machine software ERSASOFT 5 since VERSAFLOW 4. The autorouting function calculates the optimum travel paths for the microdrop fluxer and solder pots, while the definition of blocked areas prevents collisions with components. It goes without saying that the travel paths can be saved manually as well. Unlike in the wave soldering system, the solder pots of the VERSAFLOW 4/55 can move under the PCB in the x and y directions. As a result, connector strips can be processed according to length, independently of their position. This means that the pot with the soldering nozzle moves past the pins under a connector strip and thus sets up the solder connections one after another – thus minimising solder bridges per se.

Ertron mainly processes products that are soldered in the PCB panel. For this reason, the VERSAFLOW 4/55 was equipped with a double soldering module. Thus Ertron achieves double the throughput compared with a single soldering module, since two assemblies of the PCB are processed simultaneously in parallel operation. Whereas the old wave soldering system was in use for 1.5 days a week, the VERSAFLOW is now used or three to five days a week to produce the same volume. At first glance, this seems to be longer, but the deciding thing is that in terms of the overall value creation process Ertron has significantly increased product quality – the employees in equipping and rework free up capacities for other work, downstream processes in quality control also run much faster.

“We would have had a certain increase in quality with a nitrogen wave soldering machine as well. However, the VERSAFLOW offers us a significantly higher level of flexibility in electronics manufacturing. Together with the outstanding soldering quality delivered by this system, this was the deciding factor for Ertron to invest in a VERSAFLOW 4/55 from Ersa. Our customers have noticed the enhanced quality, too – which is further proof that we made exactly the right decision,” Ertron Managing Director Reinhard Probandt is pleased to report. Things can certainly continue in this spirit for both Ertron and Ersa!