Time and time again, we read about the importance of changing processes to work with Industry 4.0, Internet of Things (IoT), and smart manufacturing. We understand the significance of ensuring electronics manufacturing is automated by improving communication, monitoring, and analysis so that processes are and optimized and truly productive. We all know how important having the correct systems in place is, but are we implementing the necessary processes required to future-proof our factories? To plan actual manufacturing sequences of an intelligent digital factory, all essential process data has to be acquired and evaluated with suitable sensor technology aggregating that data to drive value-added process improvements.
One area forging ahead when it comes to intelligent solutions that answer this call is reflow ovens and soldering processes. As electronic components and PCBs get smaller and more complex, they become more difficult to reliably manufacture. These intricate assemblies require every individual solder joint to be exact and make rework unnecessary after the completion of the assembly. In practice, the quality of the solder joint is often judged by optical- or measurement-based criteria and tolerances; however, identifying objective and comparable parameters can be difficult. This is why innovative software is the key to successful soldering.
The technology employed in soldering processes has to incorporate highly advanced equipment to successfully solder assemblies of all shapes and sizes. This requires greater flexibility and increased degrees of automation and capabilities that permit self-optimization of manufacturing processes. There are companies who recognize this need and are designing intelligent systems that incorporate smart sensors capable of monitoring the condition of soldering system components, allowing for predictive maintenance to enhance the management and status of production.
Figure 1: Smart solutions, like Rehm Thermal Systems' ViCON software, are impacting processes.
Smart software and computing power are becoming more important within soldering systems, particularly for the optimization of maintenance intervals, more precise process timing, and monitoring and controlling the consumption of resources (Figures 1 and 2).
Figure 2: ViCON screenshot and machine overview.
Reflow soldering systems are now mostly optimized with regard to their control functions, energy consumption, sustainability, and manufacturing efficiency. They can be linked with a production line monitoring system that forwards data to a manufacturing execution system (MES) and enterprise resource planning (ERP). The software used in reflow soldering systems allows traceability models permitting process data, system status, alarms, and other information to be transmitted.
This is an important feature as it eliminates unreliable estimations. Because PCBs have varying thicknesses and component densities (all of which demand different profiles), by optimizing a thermal profile for every new assembly, the thermal conditions will be correct and lead to fewer failures caused by a poorly-tailored solder profile.
Intelligent software solutions can now create a system that reliably controls and monitors equipment. A leading manufacturer of reflow soldering systems has fine-tuned the technology to develop a closed system consisting of monitoring tools and various modules, each of which completes its own individual task. Enormous amounts of data are acquired by the modules from the system and monitored. Master software then compiles the data and evaluates it, for example, to keep the specified parameters constant for the respective manufacturing profile. It is systems like this that are future-proofing processes and developing data profiles. Table 1 compares current and future options for incorporation into information systems.
Table 1: Incorporation of reflow soldering systems into information systems. (Source: Rehm Thermal Systems)
To continue the development of data exchange with the reflow soldering system towards process-controlled computer-based algorithms, new smart sensors and software components will be required that are capable of communicating via a data infrastructure with numerous mechanical and electronic system elements as well as with the product to be produced.
An example of this intelligent software is Rehm Thermal Systems’ ProCap for the VisionX series. The tool monitors the stability of the reflow convection soldering for each individual product enabling optimal process traceability by tracking changes in the soldering process using temperature comparison measurements. The system detects specific heat transfer performance of the individual PCB in each of the system’s zones and evaluates this information by means of the ProCap software package. Figure 3 shows a typical temperature-time profile of a ProCap sensor while a PCB is passing through, and Figure 4 shows a screenshot of ProCap.
Figure 3: Typical temperature-time profile of a ProCap sensor while a PCB is passing through.
Figure 4: ProCap screenshot.
The data is continuously evaluated with current measurement data linked to the product database. ProCap then saves the target values for a certain temperature profile and/or product to a baseline to which it compares currently collected data resulting in specific available information. During production, verification is provided for each individual product that the selected program is suitable for the PCB to be reflow soldered. By acquiring individual heat transfer, the ProCap system permits indirect communication of the PCB with the reflow soldering system.
The ProCap software also allows for the trend of increased process-specific traceability as well as the above. Specific PCBA solder profiles can be stored against precise board identification codes within the user's ERP/MES system, giving the quality department the ability to analyse and draw out important information should it be required. It also adds specific process optimization capabilities when identifying and testing possible reflow profiles for PCBAs by giving quantifiable heat measurement data alongside the optical IPC checks to qualify the best soldering profile options.
The incorporation of soldering systems with advanced software and suitable smart sensors will not only enhance the process monitoring, but it will also help to predict failures and trigger maintenance processes on the basis of measurement data and communication with an expert system, which analyses real-time and quantitative measures of production.
Finding and exploiting the key technologies of the future to allow for smart manufacturing is crucial for long-term manufacturing success. Reflow soldering systems equipped with smart sensors and highly-advanced software will permit system components to be monitored intelligently. When incorporated with networking and data collection capabilities, these systems can be integrated to work successfully and smartly in the factories of the future. Thanks to highly developed systems and software, electronics manufacturers can intelligently increase productivity and profitability.
Joe Booth is business development and marketing manager at Altus Group Ltd.