Healthy obsession

The latest laser and micro-percussion technologies are being used to mark products in medical and other sensitive industries without contamination. Julia Pierce reports.


Confirming the traceability of products and components is increasingly becoming mandatory, so the issue of how to mark items without contamination is a big one for many industries.

Traceability has grown in importance over the past few years. Previously it was often impossible to trace the origins of each and every individual process step leading to the final product. This had caused obvious concern in safety critical applications, particularly for the provider of the finished product who would then be exposed to high levels of liability risk.

But now, the ability to mark components of any material means any faults or failures can be immediately detected and rectified no matter where their origin lies.

Laser Lines has been using Synrad’s sealed carbon dioxide lasers to show how silicone tubing used in sectors such as the medical industry can be marked. These advanced lasers are used in a variety of industrial processes including cutting, welding, drilling and marking.

Silicone tubing is widely used in the pharmaceutical and biotechnology industries where ultra-pure fluid transfer is essential for health and safety. In addition to its flexibility and puncture-resistance, the tubing is free from additives that could leach into or contaminate fluids carried inside the system.

Using WinMark Pro, Laser Lines created a mark file containing 15 sets of two-digit numeric characters laid diagonally across the mark field of an FH Series FLA200 lens. This technique allows a section of tubing to be marked with symbols measuring approximately 210mm versus the maximum field length of 165mm possible with a vertical orientation.

Text objects were created using Simple, one of WinMark’s 12 built-in stroke fonts at a text height value of 2.7mm. A string of 30 characters was marked in a cycle time of 0.68 seconds. The process used 25W of power at a velocity of 508mm per second.

‘Unlike most other marking technologies, lasers can provide high quality indelible marks on almost any material,’ said Gary Broadhead, sales director for industrial lasers at Laser Lines. ‘This is a non-contact process that does not deform or damage the part in any way. Laser marking is widely used within the medical device industry for product identification and traceability.’

Meanwhile, recognising the absolute need to avoid contamination by impurities when using its Metaletch electrochemical marking system, Universal Marking Systems (UMS) has come up with a variety of modifications. Recently it added a Remote Start Handle (RSH) meaning producers no longer have to search under the bench for the foot pedal to operate the system. A cycle start button, electrolyte feed, cycle LED and earth clamp with flying lead are all within easy reach.

The RSH can be used with UMS’s Carbon Marking Heads (M7 & M8 series) and the Saddle Marker Heads (SMH) for easy pipe and tube marking. Importantly, the SMH has a stand fitted with a sponge that is tested to ensure it does not leach any impurities allowing it to be used in controlled environments such as the aerospace and nuclear industries.

The M7 and M8 heads’ controlled electrolyte flow eliminates the need for untidy crystallised dipping dishes, creating a much cleaner working environment while reducing evaporation of electrolyte and allowing consistent, high quality and repeated cost effective marks while keeping open liquids off the workbench.

Elsewhere, Technifor has a reputation for ensuring traceability of items to prevent cross-contamination from the materials, fluids or people touching them. French legislation requires medical equipment traceability and the ability to identify the last five patients that have been in contact with a reusable medical instrument.

To achieve this, Technifor worked with a hospital in St Etienne, France, applying quality control and traceability practices to the surgical instrument sterilisation process to eliminate any potential cross-contamination of patients using a system called Medrix ID.

Based on micro-percussion technology, Medrix is designed for 2D DataMatrix marking and reading in all surgical instrument identification applications.

Technifor has now released the XF510 new generation micro-percussion marking solution, which is smaller than previous offerings with a marking window of 50x20mm. It is twice as fast as its other systems, producing 10 characters/sec. Other benefits include reduced integration costs and increased productivity with user-friendly programming. Its compact dimensions make it suitable for integration on a production line, rotary table or exiting unit. As it weighs just 2.3 kilos, it can be mounted on a robotic or articulated arm.

In the UK, Pryor has worked in a similar way with UK sterile services specialist Meditrax, providing integrated traceability and tracking systems to the healthcare market.

Using an electronic barcode-based tracking system, Traybax, it developed a system to mark and track a tray of instruments. This means hospitals know which surgeon used a set of instruments to operate on a specific patient.

Comis Orthopaedics, a manufacturer of minimally invasive implants and instruments, uses Pryor’s HP20 Nd:Yag laser marker with a V2 enclosure. This floor-standing machine has four-axis control, 160mm focal length lens and includes an electrical Z axis. It also has a circumferential fixture, an adjustable marking platform of 200x200mm and fume control for use on polymer marked plastics.

The system is controlled using the PryorLaser professional marking software on a PC connected directly to the laser system.

Recent developments from Pryor include a robust fibre laser marker with a pump diode claimed to have a mean time between failures of greater than 100,000 hours and the LOCUS low-cost, ultrasound code reader, a hand-held device able to decode Data Matrix and human readable marks concealed by paint or other industrial coatings to a depth in excess of 1mm.