This process is often used in the manufacturing of printed circuit boards (PCBs). In wave soldering, a solder wave is created and passed over the PCB, which allows the components to be joined. In this article, we will discuss the basics of wave soldering and answer some common questions about the process. We will also provide some tips to help you improve your wave soldering results!
Soldering in General
It is frequently used in electronics construction, repair, and assembly to make electronic connections between components. Soldering can also be used to attach wires onto printed circuit boards (PCBs) and other surfaces. [1]
What is Wave Soldering
The process involves passing a wave of molten solder along the top surface of the PCBs, which causes the joints between the components and board to be flooded with liquid metal. Once the wave has passed over all of the connections, it allows for fast and reliable connections in mass production applications. [2], [3], [4], [5]
How Does Wave Soldering Machine Work
If you’re still asking, “What is wave soldering?” then you’re likely wondering how the process actually works. Wave soldering machines are made up of several components that work together to make a successful connection.
Wave soldering machines use a device called a pump or vibratory conveyor to move the PCB onto an open-topped wave soldering bath. The board is usually positioned with the components facing up and away from the molten solder bath. Once in place, the board moves across the top of the bath until it reaches the exit port at which point it is removed from within the chamber.
Inside this machine, a heated element heats up the pool of liquid solder until it reaches its melting point. This liquid then forms “waves” that rise and fall on top of each other as they travel through the machine towards its exit point. As these waves move over your PCBs, they will melt any exposed metal parts such as pads, pins, and other conductive surfaces, allowing them to make contact with the solder. This is what creates a strong electrical connection between components.
The wave soldering process can also be adjusted for different types of materials such as leaded or lead-free solder, flux type, and PCB size. Additionally, many newer models can even use multiple waves for increased efficiency. After the boards have been successfully soldered, they will pass through cleaning stations which remove any excess flux from the board surface before being inspected and packaged for shipment.
Overall, wave soldering is an efficient way to achieve excellent results when it comes to assembling complex electronic circuits. With its high production rate and low cost of operation it has become a popular choice among manufacturers around the world. [2], [3], [4], [5]
Advantages of Wave Soldering
But what makes wave soldering so beneficial? Here are some of the advantages that wave soldering has to offer.
Suitable for THT assembly
Wave soldering is particularly suited for use in Through-Hole Technology (THT) assemblies. Through-hole technology (THT) assembly is a method of assembling electrical components to printed circuit boards (PCBs). It involves inserting component leads through pre-drilled holes in the PCB and then soldering them in place. THT assembly offers a reliable and cost-effective way to assemble components on PCBs, making it an ideal choice for mass production applications. Wave soldering provides a reliable, cost effective way to make these types of assemblies.
Not all soldering techniques can be effectively used for THT assembly, as some require additional materials or components to be added after the board has been soldered. Wave soldering, enables components to be soldered directly onto the board without any extra materials needed. This makes it a great choice for large-scale applications in which a high volume of parts must be assembled quickly and efficiently.
More time-saving
The wave soldering process is superior to other methods such as hand soldering and reflow techniques because it offers unparalleled efficiency and reliability. With wave soldering, the solder can be quickly heated up and applied to the whole circuit board at once, eliminating the need for tedious manual labor or complex machines required for other types of soldering methods.
The primary benefit of using wave soldering is its speed compared to other processes like hand soldering. Because wave soldering is a continuous process, it has the capability to produce hundreds of boards in a single day. Additionally, since the solder is applied in one precise wave, there’s less chance for mistakes and inconsistencies which can lead to increased production yields and higher quality products.
Cost effective
The cost associated with wave soldering is relatively low compared to some other methods of soldering. Not only does it require less time and energy than hand soldering, but the equipment used is also relatively inexpensive. Furthermore, wave solders are generally very easy to learn how to operate.
Initiates less warpage
Another of the advantages of wave soldering is that it induces less warpage on your PCBs. This is due to the fact that the solder flux and molten solder are only applied to the top side of the board, leaving the bottom untouched. This also makes wave soldering a more efficient process as less time is spent in post-processing.
Provides a strong join quality
Lastly, the huge perk of wave soldering is that it can produce a strong joint quality with minimal effort. The process involves flooding each solder joint with molten metal, creating a reliable electrical connection that won’t easily break or corrode over time. Additionally, this technique allows for quick and efficient assembly in mass production applications. [3], [5]
What is the Main Disadvantage of Wave Soldering?
Despite the many advantages of wave soldering, it does have a notable drawback. The main disadvantage is that wave soldering isn’t suitable for the very small pitches of components. If a component has leads that are too close together, it won’t be able to survive the wave soldering process. This makes it necessary for manufacturers to use alternative soldering techniques for any components with fine pitches. [2]
How to Properly Wave Solder
Now that you know what wave soldering is, it’s important to understand the best practices for using this technique. There are several key steps that must be taken in order to create a successful and reliable joint.
Preparations
What’s the first step of wave soldering? Preparations! Before you start, it’s important to make sure that the components and PCBs are properly aligned and are free of any dirt or debris. This can be done by using an automated cleaner such as an ultrasonic cleaner or a manual cleaning process. Additionally, you’ll want to ensure that all parts have been correctly placed on the board prior to soldering in order to minimize any potential issues during assembly. To do this, you need to check the following components.
Solder resist layer
The solder resist layer is used to protect any components that should not be soldered. This layer acts as a barrier between the component and the molten solder, which helps reduce the risk of short circuits. It’s important to check this layer before you begin in order to ensure that all components are properly protected. It will normally be either green or black in color, and must be inspected for any defects.
Pad spacing
The pads on the board must be correctly spaced in order to ensure that the molten solder is spread evenly across the entire component. It’s important to check this prior to soldering, and make sure that any components with multiple pins are spaced at an appropriate distance from each other. If the spacing is incorrect, it can cause issues such as cold joints or bridging between pins. And these can lead to major problems down the line.
Fluxing
Once your components and boards have been prepared, it’s time to move onto the next step: fluxing.
When added correctly, flux will help create strong bonds between components and solder.
The type of flux used depends on the application, so it’s important to select the appropriate one for your needs. Generally speaking, rosin-based fluxes are best for wave soldering as they provide excellent wetting characteristics.
For wave soldering, flux is applied to the side of the PCB that is facing up. This is done by either manually brushing on the flux or using a spray-on applicator for more precise application.
Preheating
Once the flux is applied, preheating the board before soldering is an important step. Preheating helps to promote better solder wetting and surface tension between the components and PCBs which will lead to improved joint strength. And not only that, but it will also prevent a thermal shock to the components which can cause damage.
To preheat a board prior to wave soldering, it’s best to use a hot air heater, convection oven or hot plate that can reach required temperatures. Again, be sure not to overheat your board as this could cause damage or poor quality joints. In certain cases, infra-red heaters can also be used for preheating.
Wave soldering
Now that you’ve preheated your board and applied flux, it’s time to wave solder! Wave soldering is an automated process that uses a heated metal bath of molten solder which is then “waved” over the components and PCBs. As the heated solder passes over them, it melts and flows into any gaps or pits between parts, forming a strong bond and creating reliable connections.
When setting up for wave soldering, it’s best to use a dedicated machine which already has the correct temperature settings and timer presets. This will ensure consistent results every time. Additionally, you’ll want to check any nozzles or dispensers for proper alignment, as this can affect where the molten solder travels on the board.
Make sure the temperatures are high enough to reach the eutectic point of the solder you are using, but not so high that it could cause damage to components.
Cooling
Once the wave soldering process is complete, it’s important to allow for proper cooling before handling the board. This will ensure that everything is at a safe temperature and prevent any additional damage.
The board should be returned back to normal temps in a slow, controlled manner. This will both allow the solder to become stronger and also reduce any thermal stress on components.
Finally, you’ll want to conduct a visual inspection of the solder joints and check that everything is secure and properly connected. This will help to ensure that there are no shorts or loose connections which can lead to costly repairs down the line. [2], [3]
FAQ
What is wave soldering temperature?
The temperature required for wave soldering is determined by several factors including the specific type of flux being used, size and configuration of the components being joined, as well as how quickly or slowly the wave-soldering process must move. Generally speaking, most wave-soldering machines are programmed to operate at temperatures ranging from 464 F up to 482 F. Different types of solder require different temperatures, so it is important to check the manufacturer’s specifications in order to properly program your wave-soldering machine.
What is wave soldering used for?
Wave soldering is a process used in the electronics industry to solder surface mount components to printed circuit boards (PCBs). The wave soldering machine works by heating up a pot of molten solder, which is then pumped up into an elevated wavy-shaped ramp. As the board passes over this ramp, a thin layer of solder is applied along the length of the joint and non-solderable surfaces are protected from contact with it due to specially designed masking. This efficient process provides reliable connections between PCBs and components while minimizing production time and costs.
How is wave soldering done?
Wave soldering is a metal joining process used in the manufacturing of printed circuit boards (PCBs). It is a very popular method for attaching components to PCBs as it offers several advantages over traditional through-hole mounting techniques. In wave soldering, electrical components are placed onto the PCB and then passed over an electrically heated wave of molten solder. The heat from the solder wave melts the solder on contact with the component leads and PCB pads, permanently bonding them together. Thus, it eliminates manual hand soldering operations that can be time consuming and inconsistent.
What is the difference between reflow soldering and wave soldering?
Wave soldering involves immersing the entire PCB in a bath of molten solder, while reflow soldering is achieved by applying heat to pre-tinned component pins, allowing them to melt and bond with the board’s copper traces.
When deciding which method best suits your needs, it’s important to consider the type of components you are working with, as well as their size and quantity. Generally speaking, wave soldering is more suitable for through-hole parts—components that have leads that pass through holes drilled into the board—while reflow works better for surface mount components, which have solder paste applied to their leads before being placed on the board.
Wave soldering is also significantly faster than reflow soldering, as it requires less setup time and fewer equipment adjustments. This makes it a great choice for high-volume production runs with large numbers of parts. On the other hand, if you are dealing with small batches of components or extremely fine pitch devices—components with a very tight spacing between pins—then reflow is likely your best option as it offers greater accuracy and precision than wave soldering.
What is a wave solder machine?
The welding process involves a combination of heat and pressure to create a secure connection between the components. Wave soldering machines use a specialized nozzle or “wave” to move molten solder over the board, ensuring each component is completely covered in molten solder. This method of soldering can be used for both surface mounted and through-hole components.
Useful Video: Wave Soldering Process for Electronics Manufacturing. PCB Through-Hole Assembly
Conclusion
Wave soldering is a popular method used to join components to a circuit board. It can be an effective and efficient production process that is suitable for mass production and high-volume, automated assembly lines. When properly implemented, wave soldering can produce reliable connections with low levels of impurity or defects.
In this article, we have explored some of the key concepts surrounding wave soldering. We have discussed what wave soldering is, the steps involved in wave soldering, and the advantages and disadvantages of this technique.
Wave soldering requires a combination of the right materials, techniques, temperature management and other factors in order to achieve reliable results. Careful consideration should always be given when selecting equipment for your wave soldering station so as to ensure that it meets all necessary requirements. Finally, proper maintenance and cleaning procedures should be followed regularly in order to keep the system running at optimum efficiency.
Overall, wave soldering is an effective solution for assembling printed circuit boards in high volumes. With the right setup and an understanding of how to properly use it, wave soldering can be a reliable, cost-effective method for assembling boards with minimal defects.
We hope this guide has been helpful in providing you with all the information you need to understand what wave soldering is and how best to implement it into your production process. If you have any further questions or would like more information on wave soldering technology please do not hesitate to contact us! We are always happy to answer any inquiries and provide assistance as needed. Thank you for reading!
References
- https://www.twi-global.com/technical-knowledge/faqs/what-is-soldering
- https://www.electronics-notes.com/articles/constructional_techniques/soldering/wave-soldering.php
- https://resources.pcb.cadence.com/blog/2022-the-advantages-of-wave-soldering
- https://www.mclpcb.com/blog/wave-soldering-vs-reflow-soldering/
- https://www.allaboutcircuits.com/industry-articles/a-comparison-of-reflow-soldering-and-wave-soldering/
