Above: Scannable 2D bar codes on steel created using a valvejet printer.
April, 2024: High-speed inkjet marking technology has come a long way in the last few years, and the latest advancements in print technology and ink formulations can pay significant dividends in process efficiency, versatility, speed and reliability, compared to legacy systems.
Among marking application segments, the metal industry stands out for having harsh, rugged environments and demanding equipment needs. It’s also fast-paced as shops increasingly embrace automation. Here, high-speed valvejet drop-on-demand (DOD) technology has emerged as the most reliable and efficient solution, offering crisp, durable marks that stand the test of industrial heat, oil and grime.
High-performance shops require marking systems that can keep up and operate reliably with minimal maintenance requirements. Not all marking methods and print technologies are created equal. Several conventional metal marking techniques exist, each with its own strengths and weaknesses:
• Dot peening. This method uses a vibrating stylus to create dimples on the metal surface. While durable, dot peening can be slow and potentially damage delicate materials.
• Scratch marking. A simple and affordable option, scratch marking involves using a sharp tool to create marks on the metal. However, the resulting marks are often shallow, prone to wear and tear, and may not work for harder materials.
• Laser marking. Offering high precision and permanent marks, laser marking employs a laser beam to burn the mark onto the metal surface. However, laser markers are expensive and require specialized training to operate effectively.
• Continuous inkjet (CIJ). CIJ printers create marks using a continuous stream of ink. While offering speed, CIJ inks can be susceptible to failure in harsh environments and can only make small marks. Additionally, CIJ printers require frequent maintenance to prevent clogging and other problems.
In contrast, the latest valvejet technology (when sourced from suppliers focused on the metal industry) represents a significant advancement in metal marking, addressing the limitations of other methods while increasing efficiency and versatility.
High-quality valvejet printers are specifically designed to withstand the rigors of metal fabrication environments. They possess exceptional resistance to dust, heat and humidity, ensuring reliable performance in challenging conditions. Unlike CIJ printers, valvejet technology employs a DOD approach. Ink is dispensed in precise droplets, resulting in crisp, clear and consistent marks on various metal surfaces, regardless of texture or finish.
Valvejet printers, such as the V-Series from Matt hews, feature selfcleaning printheads that minimize clogging and ink buildup. This significantly reduces maintenance downtime, keeping production lines running smoothly. In addition, the most advanced valvejet technologies deliver exceptional marking speeds, seamlessly integrating into demanding production environments without sacrificing efficiency.
WIDE SPECTRUM OF USE CASES
Valvejet printers can mark carbon and stainless steels and aluminum. They adapt effectively to various surface textures and finishes, ensuring consistent mark quality. They also are capable of handling virtually any ink type. This is a critical must-have for meeting the diverse requirements found across the metals industry. For example, some marks must be permanent. Other uses require marks that are removable, such as internal tracking codes that need to be removed for aesthetic reasons or replaced in a different stage of production.
Some inks are only visible under UV light, making them useful for internal codes that do not need to be visible in the finished product or for tracking codes on finished products. Inks may have specific formulations to meet compliance requirements, like aerospaceapproved or halogen-free.
Manufacturing conditions and requirements also drive the selection of ink types. Extra high-contrast inks, such as white pigmented ink, are often used for marking on dark metals. There are specialty inks, like MEK and acetone-based inks, that can penetrate through oils, lubricants, coatings and mill scale. Some applications require adhesive, fast-drying ink formulations to avoid smearing. And often inks must be heatresistant to mark on hot metal and/or for the marks themselves to stand up to high temperatures.
DRIVING EFFICIENCY
The growing adoption of valvejet marking in the metals industry is driven by the technology’s proven performance, reliability and cost advantages. As businesses strive to optimize their operations and enhance product quality, the flexibility and efficiency of valvejet marking systems make them a top consideration in the buying process. With ongoing innovations and a broad selection of ink formulations, the potential applications for inkjet marking continue to expand, promising even greater benefits for the metals industry.
Written by: Kevin Havre a global product manager for Matthews Marking Systems http://matthewsmarking.com/, a supplier of industrial marking and coding systems.