Seal integrity testing is non-negotiable when dealing with plastic tube packaging because the strength and reliability of the seal directly impact product quality and consumer safety. For MSD Ltd. and its clients in pharmaceuticals, medical devices, and food packaging, ensuring strong seal integrity in our tube filling and sealing machines is part of our commitment to excellence. 

But how do we guarantee this essential quality? This guide examines the common challenges, best practices, and advanced testing methods for maintaining impeccable tube seal integrity.  

Why Seal Integrity Matters in Tube Packaging

Seal testing of the tubes holding medical creams, ointments, chemical liquids, and glue is essential for user safety and optimal dosing. Leaking tube seals can cause product contamination and compromise shelf life, leading to costly and frustrating product recalls and damage to a brand’s reputation.

Common Plastic Tube Sealing Issues and Their Causes

Weak tube seals are a frequent concern for any product manufacturer. These can arise from worn-out heating elements or misaligned sealing jaws. Issues like this affect the heat-sealing process, making plastic tube seals prone to failure. 

Misaligned jaws can apply uneven pressure, compromising the tube seal strength. Inadequate tube end heating or faulty heating elements further exacerbate the issue and prevent the proper fusion of tube ends. There may be compatibility issues with tube materials as different plastic types require varying sealing parameters.

Optimising Heat-Sealing in Tube Filling Machines

Achieving an optimal tube seal requires precise heat, correct pressure, and tight control of the dwell time. Your production line may produce different products, which means switching to a different tube material requiring a new heat setting. 

Machines like those provided by MSD Ltd. offer adjustable parameters to ensure consistent results. 

You can use various testing methods to ensure tube seal integrity, such as Burst testing, a destructive seal testing method that measures the seal’s ability to withstand internal pressure. 

Non-destructive seal testing methods, such as vacuum decay and dye penetration testing, are also options. Vacuum decay testing detects micro-leaks by monitoring pressure changes, while dye penetration testing uses coloured solutions to identify leaks. Headspace analysis and tracer gas leak testing can also be used.  

Best Practices for Routine Quality Control

We highly recommend setting up regular inspections, periodic calibration, material compatibility testing, and statistical process control (SPC), which are all vital for maintaining excellent seal quality control. 

Machine operator training is also crucial, as it ensures your staff understands when and how to perform correct seal integrity testing. Adherence to ASTM standards for seal integrity testing and ISO standards for package testing enhances your quality assurance.

Choosing the Right Plastic Tube Filling Machine

Using the most appropriate tube-filling machines on your production line is the best way to achieve consistently high tube seal integrity. Fully automatic machines can streamline high-volume production, while semi-automatic and manual machines are best for lower volumes, new product testing and more specialised applications. 

Material compatibility is also important, and machines should be capable of handling various tube packaging materials without risking seal quality. Your production volume and product accuracy requirements must align with your machine’s inherent capabilities. Regular machine maintenance and support, such as those offered by MSD Ltd., ensure sustained performance and minimise downtime.

Regulatory requirements for packaging integrity are stringent in highly regulated industries. Understanding the importance of seal integrity for maintaining aseptic and sterile packaging for medicines, such as topical creams.

How MSD Ltd Can Help

Manufacturers can take proactive measures to prevent many issues. Undertaking seal failure testing and conducting regular analysis is crucial for identifying and fixing packaging defects. MSD Ltd. offers effective tube integrity solutions so that you can address these challenges. 

We offer comprehensive seal testing solutions, including non-destructive and destructive methods, to ensure your packaging meets the highest standards. Contact us for seal integrity solutions, request a quote for seal testing, or learn more about our services.

By implementing these best practices and utilising advanced testing methods, manufacturers can ensure the seal integrity of their product tubes, safeguarding product quality and consumer safety.