Timely inspection of punch tooling and mechanical components for wear condition is conductive to extend their service life and improve productive efficiency. Regular inspection of punches and dies is not a case of time or labor wasting, but a guarantee for high quality tablets. Once found worn, we should take prompt measures to correct it, or replace a new one if badly worn. If we ignore the worn parts and let them continue to work, defect tablets will continuously occur, resulting in great losses for companies as well as customers. This article will clarify how to measure punches and dies and how to correct all the defects.
►Punch Tip Wear
Before measuring punch tab tooling to check its worn conditions, we should have a good understanding of exhaustive dimensions of tablet compression tool and how they affect tablet quality.
The correct method is to measure the working lengths to see how much they deviate within the station of punches. Start by selecting a datum(reference punch) from the target punches. Then compare its dimensions to those of the other punches to see whether thy are within 0.002 inch from shortest to longest. Replace the punches that fall outside that tolerance.
Then it comes to discuss the wearing of tip, and how it causes defects of tablets, and ways to correct it.
Common causes of punch wear:
- Use new punches with worn dies, or worn punches with new die;
- Worn die pocket leading to misaligned dies;
- Worn punch guides and key-ways leading to misaligned punches.