To minimise losses in the production of tablets, advancing and automating methods for measuring pharmaceutical compression tooling is crucial, says Mariusz Stachera
Despite the technological development in the field of process optimisation in the pharmaceutical industry, the use of measurement practices to assess the wear of punches and dies is not yet widely used. Observations show that in some companies producing drugs and supplements, the evaluation of the wear of the compression tools is still based only on the optical examination of the working part of the tools – or, worse, no measurements are carried out, which may lead to increased discards or major failures.
Punches and dies are one of the most important, and at the same time the most delicate, tools used in the production of tablets that work in an environment that always causes natural wear of these. The measurements ensure the preservation of geometric, weight and information parameters (embossing/score line) of the manufactured preparations, and thanks to them, it is possible to diagnose:
- Natural wear of the punch,
- Damage to the working part,
- Damage to the shaft and head of the punch,
- Damage to the die hole resulting from natural wear (ringing) and mechanical damage
- Quality of embossing/score line
Manual measurement carries the risk of errors
In most companies, the measurements are carried out manually using contact sensors, requiring the operator’s professional knowledge in the field of metrology, experience in the industry and simply a good focus on the activities performed. The manual measurement method can also introduce a series of errors both due to the measurement tools themselves and the transposition of the measured data to the measurement reports. The total time to perform the expected measurements with the use of several points and measurement positions for one tool is also significantly extended.
Fortunately, more and more often the validation departments in the pharmaceutical industry impose the necessity of measuring the tools already at the production stage. Both in terms of measurement methods as well as tolerances and quality of measurements, these requirements become more and more stringent. There is also often question of the measurement methodology applied so far. The latest technological developments in the field of optical metrology have made it possible to introduce improvements in measuring tools and move away from outdated methods. Currently, measuring machines are equipped with high-quality sensors, ensuring high accuracy and measurement speed.
Knowledge in the field of measurement requirements and the latest achievements in the field of measuring technology has enabled Adamus to provide high-quality measuring machines for punches and dies on the market. The device for dimensioning uses full automation of processes in the scope of not only measuring but also at the level of tool delivery to the measuring chamber using the robot’s arm.
Measuring machines, based on the obtained measurement results, perform the pairing of punches. Automatic pairing algorithm allows users to minimise production losses due to the weight loss of tablets. The latest solutions enable the pairing of repeatedly popular multi-tip punches in the industry.
On the market, there are models of machines equipped with a camera and image analysis algorithms, thanks to which it is also possible to measure the embossing on the punch bowl. Measurements of that are made with an accuracy of up to 1μm, thus eliminating the risk of defective batches of products. Furthermore, some measuring solution delivers database directly connected to the measuring system. That database, filled with historical and current measurement results, allows analysis of consumption trends. This makes it possible to order tools for maintaining production continuity before they are used up.
In the current production reality and with the high expectations of the consumer market, it is necessary to provide solutions that meet those expectations and even anticipate them. Automation of the measurement process while maintaining a professional, strictly dedicated to the pharmacy approach, provides not only what the final product recipient expects – tablets – but also minimises losses during production, including emergency technological breaks caused by tools whose quality was not monitored.
Mariusz Stachera is with Adamus