Electronic PCB assembly services provider, Hindley Circuits, has recently taken delivery of its new Miele PLW6111 aqueous cleaning system to satisfy a new high reliability contract.
Graham Fraser, Managing Director of Fraser Technologies Ltd., the exclusive supplier of Miele equipment into UK electronics manufacturing, describes some of the benefits of aqueous cleaning with the Miele equipment.
The assembly of printed circuit boards (PCBs) requires precision and expertise to ensure the boards are reliable and fully meet customer specifications and expectations.
Not only is the correct assembly crucial, but for many assemblies and products, it is essential that all traces of flux residue from the soldering processes have been removed.
Occasionally this is only for aesthetics, but more usually this is to ensure high reliability, and provide a clean surface for other processes, such as conformal coating or potting, and remove any residue that could inhibit performance.
For high-reliability industries, such as automotive (EVs), energy, aerospace and defense, etc., it is even more imperative that the PCBs perform exactly as required with minimal risk of failure.
One of the many ways assemblers ensure this high quality is through rigorous cleaning of the PCBs.
Hindley Circuits is a well-known provider of electronic PCB assembly services for a variety of industries throughout the UK.
After winning a new manufacturing opportunity in a high-reliability industrial sector earlier this year, Hindley’s operations team evaluated the cleanliness requirements and determined that cleaning was essential to fulfilling their customer’s needs, and to obtain better results with an improved turnaround time.
Choosing the right cleaning process or equipment
After considering process options and whether to use solvent or aqueous solutions, the engineering team completed trials with the Miele PLW6111, which is the larger chamber system of the PLW6000 range.
The results achieved using Miele’s SlimLine PLW6111 aqueous cleaning machine from Fraser Technologies met all of their customer’s requirements, not only for cleanliness, but for equipment size and throughput capabilities.
The Miele option provides a complete solution and the team at Fraser Technologies conducted several trials to ensure Hindley achieved its optimal results and met all cleanliness standards. They also provided a final specification, including a purpose-built, externally-heated chemical isolation tank, and bespoke basket options with dedicated inserts for supporting the PCBs.
Once installed, the engineers at Hindley were able to tweak the programmes, experimenting with the variety of wash times and temperatures. Whilst the first run of boards were cleaned immaculately, the team discovered they could reduce the time by a quarter and achieve the same results. As a bonus, Hindley found it could also clean its wave solder pallets, further enhancing the value proposition.
Aqueous cleaning in action
The high-reliability project requires the PCBs to meet all standards of IPC-A-610 Class 3, which specifies that there are less than 1.56 µg CaCl/cm². The Miele machine meets these requirements, while also providing gentle cleaning on delicate boards.
The Miele SlimLine is a single chamber aqueous cleaning system measuring only 65cm wide, providing a large internal capacity within a small footprint.
It offers a flexible chamber space, allowing a wide range of components to be cleaned quickly at the same time. The larger PLW6111, as installed at Hindley, has the capacity for up to three slide in baskets, which can be located at four different heights.
The machine provides a smart load system, flexible and intelligent controls, a highly efficient cleaning process, a wide range of load carriers and accessories, and it allows for visual monitoring of the chamber via a glass window with internal lighting.
All of these benefits were important in Hindley’s decision to select Miele. The footprint was key as they did not have a lot of space for a new piece of equipment in the existing plant room and needed it to fit into a small area. The large internal size of the chamber was also imperative to ensure the process was not a bottleneck for the quantities needed to clean each day, along with the speed of the wash and the ability to adjust settings as required.
Hindley cleans 108 PCBs per day in the Miele machine and can accommodate 64 in one wash. The team has also started cleaning products for other projects in the machine due to the quality of results.
Steve Crosby, Engineering Manager at Hindley Circuits, commented on the results of the machine:
“We’ve been really pleased with the results of the Miele machine over the last few months. The team at Fraser Technologies were extremely thorough in conducting trials and ensuring they provided us with the right solution for our requirements. Once the machine was in situ, it only took a minimal amount of experimentation for our team to find the programme that worked well for us and we’ve made a seamless transition to this cleaning process since.
“The machine itself is simple to set up and modify, and the loading and unloading is efficient. It offers the consistency and reliability we need and the results are exemplary. Our engineering consultant, who works with a variety of businesses and has supported the provision of cleaning equipment for others, said that this is the best wash plant he has ever come across. We can see this ourselves in the results, but it’s great to have it backed up by another industry expert.”
Roy Goshawk, Sales Manager at Fraser Technologies, said:
“This is an innovative aqueous cleaning machine from a high-end manufacturer with a reputation for excellent reliability and strong customer support.
Hindley Circuits experienced flux residue on its boards, and we knew that a machine like the Miele SlimLine, combined with our chemistry, could thoroughly remove this residue without damaging the fragile PCBs.
Miele is unique in guaranteeing that parts used for the manufacture of their equipment will continue to be available for a minimum of 15 years.
“We are really happy to see that Hindley has achieved the results it required, and that its own customer is satisfied with the quality of the products.”
Miele SlimLine aqueous cleaning applications
As well as electronics PCBs, the machine is suitable for a wide variety of components and specialist cleaning applications in the automotive, medical devices and aerospace industries. Combined with the right chemical, it is especially effective for flux removal and for other parts cleaning and degreasing applications.
The results achieved using Miele’s SlimLine PLW6111 aqueous cleaning machine from Fraser Technologies met all of their customer’s requirements, not only for cleanliness, but for equipment size and throughput capabilities.
The Miele option provides a complete solution and the team at Fraser Technologies conducted several trials to ensure Hindley achieved its optimal results and met all cleanliness standards. They also provided a final specification, including a purpose-built, externally-heated chemical isolation tank, and bespoke basket options with dedicated inserts for supporting the PCBs.
Once installed, the engineers at Hindley were able to tweak the programmes, experimenting with the variety of wash times and temperatures. Whilst the first run of boards were cleaned immaculately, the team discovered they could reduce the time by a quarter and achieve the same results. As a bonus, Hindley found it could also clean its wave solder pallets, further enhancing the value proposition.
Aqueous chemical cleaning solutions, which can be used in this system, can be applied to a variety of metals such as copper, stainless steel, and brass to remove grease, cutting fluids and general particulate.
Graham Fraser, Managing Director of Fraser Technologies, said:
“The equipment offers a high level of flexibility with intelligent controls, including a wide range of load carriers and accessories. And with the added value of our custom made chemical isolation tank, this system can recirculate and reuse the chemistry, further reducing costs and environmental impact.
“We have a strong relationship with Miele after years of collaboration, and very much share its values for high quality, sustainable and innovative cleaning systems. As the exclusive UK distributor for this equipment, we have been really pleased with the results our customers like Hindley Circuits have seen to date. We’re looking forward to rolling the system out to more manufacturers across the country.”
Fraser Technologies is a leading provider of both aqueous and solvent cleaning solutions and equipment. The expert team looks at each job individually, offering trials and personalised customer service, and advises on the cleaning fluids, cleaning systems and equipment that are correct for each individual business and provide optimum performance requirements.
Hindley Circuits provides the highest quality PCB assembly services for clients across the globe operating across a diverse range of sectors. With investment in the latest technology and upskilling of its staff – who are all fully trained and have been independently assessed in accordance with IPC-A-610 standards – they can deliver even the most intricate of PCB assembly services to the highest levels of accuracy.
For further information, visit frasertech.co.uk and hindleycircuits.co.uk.
