Moving beyond manual methods: laser labelling in electronics manufacturing
The UK is home to a substantial portion of the world's contract electronics manufacturing (CEM) sector, producing high volumes of critical, high-value electronics like medical devices, automotive and telecom equipment.
The complex, high-mix production prevalent in the region has driven a focus on quality control and traceability which is essential for highly automated and digitised manufacturers embracing Industry 4.0 practices. In these production environments, many questions come from manufacturers on how to improve the product identification process, where customers feel that manual product labelling used to identify and monitor parts is proving to be inadequate to meet the stringent demands.
Labour shortages in the UK mean that CEMs are looking to automate many repetitive, manual processes. This has exacerbated traceability challenges further. In response, a growing number of manufacturers are transitioning to automated laser marking systems for product labelling to address these traceability gaps.
Joe Booth, CEO Altus Group further discusses.
Manual labelling – the good and the bad
Manual labelling has previously served as a reasonably simple and inexpensive option for basic product identification. Workers could quickly apply pre-printed stickers by hand or add markings with stencils or ink pens to designate logos, serial numbers, and barcodes. This made manual labelling an appealing starting point when production volumes were smaller and products less complex. However, as manufacturing has scaled exponentially and products have become more sophisticated with exacting specifications and traceability requirements, manual methods have proven to be limited in meeting the demands of electronics fabrication. However, it does have its place; for prototyping and early development, manual labelling could be a good option.
The low cost and flexibility of a ‘simple sticker’ allow workers to rapidly apply and modify labels on prototypes as designs evolve. This adaptable label placement enables quick iteration without specialised equipment. However, as production volumes have increased, products have become more sophisticated, and technical specifications have grown more exacting, manual labelling has proven limited in meeting the complex requirements of cutting-edge electronics manufacturing.
There are several drawbacks when using manual labelling methods:
Human error and inconsistency
Manual label application depends on the individual workers, with the most skilled operator making occasional mistakes which are increased across long production runs. Different operators also apply labels differently. Such inconsistencies and inaccuracies in component identification can lead to defective products, recalls, and traceability problems.
Manually adding individual labels onto components is a slow process, especially with small electronic components. Even for an experienced worker, manually handling and positioning each tiny label is time consuming. The more labels required per product, the greater the time involved. This manual process becomes highly labour intensive and a bottleneck for production flows, significantly decreasing manufacturing throughput and efficiency.
Lack of adaptability
Pre-printed labels used in manual labelling have minimal flexibility when design changes are required. Companies using manual labels must discard obsolete label stocks and order new pre-printed labels whenever they want to adjust label content or position. This wastes inventory and requires production downtime during changeovers. Pre-printed labels also cannot generate unique serialised numbers, enable customisation, or easily mark variable data like date codes. If labels are printed on the fly, this reduces the impact of limited adaptability.
The adhesives used in manual stick-on labels can begin to fail over time when exposed to repeated humidity, high temperatures, abrasion, or chemicals. Labels can peel, fall off, become illegible or disappear completely – resulting in products with missing or incorrect identification. This makes ongoing traceability and warranty tracking difficult.
Manual labels can only be applied on accessible surfaces with enough area for adhesion. Odd shapes, small sizes, and hidden areas restrict where labels can be placed. The labels are limited in what materials can be used and must meet size requirements for human handling. These constraints limit options for product design and labelling locations.
Additionally, manual labelling cannot provide the permanent marks mandated by certain regulatory requirements like unique device identification (UDI). Overall, the many limitations and disadvantages inherent with manual labelling make it unsustainable for smooth, high-quality electronics production.
Laser labelling addresses limitations of manual methods
Automated and precise, modern laser marking systems surpass the limitations of manual labelling by offering permanent marking capabilities. One argument that manufacturers may say is a disadvantage is the initial outlay of the equipment, however, it has numerous advantages that far outweigh the investment cost.
These systems have become integral to the production line, prompting CEMs to opt for laser marking technology.
Permanent markings for lifelong traceability
Lasers create marks by altering the surface structure of materials through ablation, oxidation, melting or other photochemical processes. This means labels become integral, permanent parts of the product itself - not just stuck on. Laser marked identification withstands wear, abrasion, temperature extremes and chemical exposure. Electronics OEMs can trace labelled products across their entire lifecycles.
Precision marking and legibility
Lasers can mark intricate details and small font sizes down to micron levels. Complex machine-readable codes like barcodes are imprinted with perfect precision and accuracy. This prevents errors in component identification - especially critical for complex miniature electronics parts. Lasers easily mark unusual shapes and designs, including curved, angled or hidden surfaces unavailable to manual methods.
Laser marking is a non-contact process. It does not require physical contact with the PCB surface, unlike ink printing or mechanical engraving methods. The laser imprints marks by directing focused light energy onto the material to alter its structure without touching it. This non-contact process eliminates any risk of causing damage, distortion, or stress to delicate electronic components during marking. This enables safe, clean, and damage-free identification of even the most sensitive, densely-packed PCB designs. It can also be used on various surfaces, from metals and ceramics to laminates and plastics, making it ideal for modern high-mix electronic components.
Fast and integratable
Laser marking seamlessly integrates with fully automated production lines and material handling systems. Parts can be precision marked quickly with no manual intervention. Programmable laser systems also enable rapid changeovers between label formats and data variables. This allows for high-throughput production runs without delays.
Laser systems excel at on-demand marking of labels with variable information like dates, times, and serial numbers. Programming is fast and flexible - allowing for quick customer-specific customisation.
Stringent government traceability regulations like UDI require permanent product labels that remain intact over long periods and harsh conditions. Laser marking satisfies labelling permanence regulations that manual methods can’t.
Laser labelling – the clear choice for advanced electronics
After considering the advantages and disadvantages of manual and laser labelling, it becomes evident that laser technology is the best option for today’s electronics manufacturing. The many drawbacks and bottlenecks inherent in manual methods now hinder quality, throughput, and responsiveness. Laser labelling addresses these shortfalls and enables state-of-the-art production.
Laser systems fulfil the rigorous demands of high-precision Industry 4.0 electronics production environments, enabling immediate and flexible product identification, intricate coding, automated workflows, and guaranteed label permanence.
As electronics manufacturing progresses into smart factories with data-driven production strategies, laser labelling integrates seamlessly into these advanced concepts. Laser systems interface directly with central automation controls, production databases, enterprise resource planning systems and machine learning platforms. This integration enables laser-marked labels to become essential components of advanced PCBA manufacturing practices.
Electronics producers looking to maximise efficiency, quality and reliability will gain a competitive advantage from using laser labelling. Laser labelling emerges as an enabling technology for CEMs looking to meet accelerated time-to-market schedules while still satisfying customer requirements, trade regulations, and traceability requirements.