Reflow Soldering
November 2023
In the constantly evolving landscape of electronics production, the industry is faced with a multitude of challenges arising from more and more new applications. On the one hand, there is the ongoing trend towards ever smarter devices with more functions, and on the other, the rapid growth of power electronics. Miniaturization versus heat dissipation, gigahertz versus megawatts, hundreds of components on a thumbnail versus transistors the size of a matchbox. And somewhere in between is industrial electronics, which needs a little bit of everything. Adapted joining technology is required to meet all these requirements. Ersa GmbH supplies the right system for every application.
Soldering is still the most important joining technology in electronics today. And for good reason. Soldering is unrivaled in flexibility, can be scaled excellently and offers the full range of components. Soldering does not place any special requirements on the PCB and the various processes allow almost any application to be realized.
Soldering is suitable for all applications. From low-cost to high-end, small or large components, there is a suitable soldering process for everything. Especially in the area of very large quantities and price-sensitive products, there are actually no alternatives.
The majority of the components, in relation to the number of units, are assembled using SMD technology. Several thousand components per assembly are not uncommon. This is another reason why chip designs in particular are becoming smaller and smaller. At the same time, however, the range of components is becoming ever wider, so that components that were previously firmly rooted in through-hole technology (THT) are also being processed as SMDs. This requires powerful reflow ovens such as the HOTFLOW series from Ersa. Because only high heat transfer guarantees low temperature differences across a wide range of components. This delta is elementary for the highest quality, as it ensures that high-mass components can be safely soldered, while small components do not overheat.
Add to this the requirement for maximum throughput and you end up in the premier class of reflow ovens. Just like the HOTFLOW THREE from Ersa, which sets benchmarks in every area. Optimal heat transfer and even heat distribution in the oven are achieved by the highly developed flow concept. All aspects were considered in the design of the convection: an optimized zone separation allows sensitive profile adjustment, the intelligent fan units combine high performance and efficiency. The thermal performance with up to 26 heating zones enables very high throughput, which can be further increased by options such as two-track conveyor system. All this makes the HOTFLOW THREE one of the most high-performance reflow systems on the market. But even the best machines cannot produce if they are not maintained. This is where the revolutionary condensate management of the HOTFLOW THREE comes into play. One of Ersa's primary objectives during development was to reduce downtimes. The result is a three-stage cleaning concept that offers a customized solution for every zone. This allows the HOTFLOW THREE to achieve maintenance intervals of 12 weeks or more, even at maximum throughput. This high availability gives Ersa customers a significant competitive advantage.
The triumph of selective soldering is a reflection of developments in electronics production. The applications are becoming more and more diverse, the component variants are increasing. No other process can meet this range of challenges better than selective soldering. And no other supplier offers a broader portfolio than market leader Ersa. From the SMARTFLOW and ECOSELECT entry-level models, for small to medium-sized series, to the VERSAFLOW 4, with versions for large assemblies or maximum throughput. Ersa offers the right machine for every requirement.
The same functional elements are used in the fluxer, preheater and soldering module across the entire system range, from the ECOSELECT and VERSAFLOW ONE to the VERSAFLOW 3 and 4. This has the great advantage for the user that a standard soldering process is available in all selective soldering systems from the world market leader Ersa, which is compatible across the entire range of systems and is therefore interchangeable and comparable. This gives the user the security of only having to qualify the selective soldering process once if this is required by the customer.
The VERSAFLOW ONE is the new entry level into the VERSAFLOW world of selective soldering. It offers inline technology at the price of a batch machine. The ONE is the first system in its class to offer the option of two pots per soldering module, the distance between which can be adjusted manually in the conveyor direction. It is therefore the ideal choice for small and series production of simple assemblies that require reliable technology with high throughput. The VERSAFLOW ONE includes all the features of the series and thus builds on Ersa's decades of experience in selective soldering. It has a 3mm pin chain conveyor and program-controlled width adjustment as standard for maximum flexibility and performance. The flux module is based on well-proven multidrop system with one or two flux heads and numerous options. The precision of the multidrop fluxer enables almost any possible geometry.
The basic version of the preheater is equipped with a short-wave IR heating module from below. Top heating with convection in the preheating unit is available as an option. Contactless monitoring of the PCB temperature in the preheating module guarantees maximum process reliability. Many automatic features such as automatic nozzle activation or solder wire feed increase availability and therefore throughput. Last but not least, they improve user guidance, for which the Ersasoft 5 operating software has also been optimized. In addition, the VERSAFLOW ONE has the latest smart features such as traceability and a connection to the KE Connect platform, making it a safe investment to be prepared for future requirements in digitalized electronics production. With over 2000 systems installed worldwide, the VERSAFLOW 3 series systems are the workhorses in the field of selective soldering technology. Extensive options are available in this series, allowing the systems to be equipped with up to six soldering pots in three soldering modules. Building on the features of the VERSAFLOW 3, the flagship VERSAFLOW 4 offers additional flexibility in the field of fluxing and soldering. The optional Ultra-Flex modules in fluxing and soldering are designed in such a way that two fluxing heads or soldering pots are arranged on two separate, independently operating axis systems, each in one module. The user has the option of freely using X, Y and Z variability for processing assemblies. This flexibility offers the highest degree of variable usage possible with
automatic programming. This variability is the reason why this system is virtually a standard in the production of soldering-heat-intensive inverters for e-mobility and the PV industry.
It is precisely in this area that press-fit also shines. During press-fitting, components or pins are pressed into the PCB without any additional heat input. The technology has a number of advantages such as greater reliability of the joints, no heat load, energy savings and greater cleanliness due to the absence of flux. Nevertheless, for a long time press-fitting led a niche existence, limited to connectors and pins. It was the boom in power electronics that gave press-fitting a new boost, and the market is developing rapidly. This is because press-fit connections enable significantly lower contact resistances than soldered joints. This is an unbeatable advantage when using several hundred amperes on PCBs.
Ersa took the market development and customer feedback as an opportunity to also develop a system for press-fitting. The VERSAFIT 500 is a logical addition to the Ersa portfolio. Here too, the aim was to maximize performance, quality, reliability and throughput. This makes the VERSAFIT 500 a real booster for customers' competitiveness.
The VERSAFIT 500 is a highly flexible inline system whose core component, the press cylinder, is servo-electric and can therefore be precisely controlled and monitored in terms of force and travel. The press cylinder is mounted in a stable metal frame, which prevents inaccuracies caused by twisting during pressing. This eliminates the need for movable tools or other compensation mechanisms, which are commonly found on many presses.
The assemblies are positioned under the pressing tool using a high-precision X/Y table, which is also the conveyor system for the assemblies. In order to meet the requirements for high flexibility, the VERSAFIT 500 has a magazine for a wide variety of press-fit tools. The user defines the tool change and its selection, as well as the associated process parameters, in the control program. A program is activated via known coding of the assembly or workpiece carrier. Process control during the press-fitting process is extremely important. The VERSAFIT 500 system enables the evaluation of various parameters such as force, travel or gradients. The data is recorded and is also available for further processing in other systems via interfaces.
Whether electronic assemblies for in-ear headphones the size of a fingernail, 5G antenna systems with a length of 3 m, thick copper circuit boards for power electronics or high layer multilayers for communication technology - Ersa's systems cover all these applications. Ersa systems are characterized by flexibility down to the individual process parameters for each individual joint, as well as high demands on throughput and quality. This variety of systems, combined with a worldwide service network and individual process support, gives Ersa's customers the security of the highest quality and availability at low cost and optimum efficiency.