The Negative Effects of Reusing Syringes and Accessories

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Every component in the Timed and Pressure dispensing system plays an important role in controlling the accuracy and repeatability of the dispensing process.  To meet the high accuracy and repeatability rate desired in most applications, the syringe barrel, piston and dispense tip are designed for a one-time use only. 

Here are reasons why:

A high-quality syringe barrel is designed with zero draft ID.  This feature allows the material dispense consistently.  During the dispensing process, the syringe ID can be stretched out of round.  If the barrel is reused, this stretching can cause the barrel- piston assembly to fail. In addition, the piston seal will be worn out. This effect will create a few issues such as material blow-by and the leaked material will migrate back to the dispenser. Secondly, air can drift around the piston and entrap in the dispense material which can cause moisture sensitive material to cure prematurely.  Lastly if the syringe barrel is out of round the dispensing output will be inaccurate and inconsistent.

Dispensing needle is impossible to be clean out completely. Adhesive residue inside the needle will create turbulent flow which can generate minuscule air bubbles. Eventually, the residue will completely obstruct the material path impacting quality.   

The main reason companies decide to use recycled consumable parts is to reduce manufacturing cost. Reusing consumable dispensing parts is not the right way to reduce cost.  Before making the decision to recycle syringe barrels, pistons and dispense tips, manufacturing managers should do a thorough study to see if the practice is worth the risk. 

While some manufacturing processes do not require good process control or dispensing repeatability and contamination control, most manufacturing processes are designed to address these issues. Most managers agree that replacing barrels, pistons, and dispense tips after one use, reduces rework and quality issues and reduces material waste and overall process cost while improving product through-put and improving product performance.