Until recently the methylene blue dye leak testing method has been used for blister packed tablets. This process, being messy, destructive as well as dependent on human errors, has now finally been replaced by a clean, precise, non-destructive leak tester that can easily be validated to detect, from cracks down to micro-leaks.
The compact LF-BLI machine is ideal for sample testing between the existing Blister Line and Cartoner Packing line. The blister packs are manually inserted on a test base, which may take up a number of blister packs depending on the size. A sensitive membrane is then sealed on the test base and a vacuum is applied, which (when set under a predetermined vacuum) will analyse the swelling of each blister cavity, thus indicating which blister pack is faulty. The machine will also indicate which cavity is leaking.
The main advantage of this machine is that no extra tooling is required for different size blister packs as the sensitive membrane will adjust to any size and shape. The LF-BLI machine is fully computerised utilising a SCADA platform. The software is easy to operate and includes utilities such as a products database and statistical reports. A printer may also be installed for printing test results and parameters. The technology is highly precise and fully validated.
The advantage is that the machine has a very fast pay back on investment and will save money for the company. Destructive testing using the methylene blue dye method can cost from €500 per day. With some expensive tablets it can cost even more. There is also a cost to discard the product. With the LF BLI machine the manufacturer can save the blister packs that have no leaks and have the payback of the machine in a few weeks.