Terminology of punch and die structures in tablet press

Tablet manufacturing is a common process in pharmaceutical plants. Understanding and utilizing the correct terminology for punch and die construction can help technical teams (RD, QA, QC, production, engineering) more conveniently analyze the causes and solutions to common technical problems.

Introduction

The punch and die set in tablet production includes the main components: upper punch, die and lower punch. All components are fabricated from high-hardness alloy steel to withstand adverse conditions such as high compressive forces and corrosion. Punch and die sets come in a variety of shapes and sizes to suit different production requirements. The punch and die in a tablet press have different structures and operations depending on the type of machine.

• In the Eccentric Tablet Press, the upper punch moves up and down, while the lower punch remains stationary. The upper punch is attached to a moving piston to create tablet compression force. The upper punch is ribbed, and in some cases, a locating pin may be included to ensure precise positioning when the punch is not perfectly round in shape.
• In Rotary Tablet Press, the upper punch, lower punch and die are mounted on three parallel rotating trays, rotating together with the tray when the machine is operating. The punch head is designed with a flange of a specific size to slide along the guide cam, giving the punch additional up and down movement when moving to the compression station. This mechanism helps the compression process to take place continuously and efficiently, optimizing tablet production.

You can refer to the article Bản chất của chày/cối trong ngành công nghiệp sản xuất dược phẩm

Some terms about punches and dies
The structure of the punch includes the main parts such as: The punch head, punch neck, punch body and stamping head are shown in the following figures:

Conclusion

In summary, understanding the terms of punch and die construction is the foundation for further research on the events occurring during tablet compression as well as understanding the possible causes of common problems during tablet cossmpression.

Reference

• Qiu, Y. Chen, G. G. Zhang, L. Yu, and R. V. Mantri, Developing solid oral dosage forms: pharmaceutical theory and practice. Academic press, 2016.