While Masterflex® tubing is designed to deliver top performance, all tubing has a limited number of times it can be compressed before breaking. Generally, over time, the tubing will wear and break. When this happens, it most often splits along the longitudinal axis where the most stress occurs. This is a function of the tubing material and the wall thickness to inside diameter (I.D.) ratio.
In another scenario, you may experience a loss of 50% of the flow rate. In this case, when the tubing is released from the rollers, it loses its ability to snap back to its original shape. Thus the flow rate decreases substantially because as the tubing regains its shape the vacuum created behind the roller decreases with fatigue. The fluid will not be pulled through the pump head as quickly. This is also a function of tubing material and wall thickness to I.D. ratio.
To increase your tubing life:
Slow down the speed of the drive. This decreases the frequency of compressions of the tubing. Use a larger tubing size to maintain the same flow rate.
Select a thick-walled tubing to increase the number of compressions required to wear the tubing out. It will also increase its memory capacity (for example, size 25 and size 15 tubing both have the same I.D. with the same flow rate, but size 15 has a thicker wall and will last longer).
Choose the tubing formulation with the longest life that is also compatible with your fluid. Norprene® and PharMed® offer the longest life while C-FLEX® and silicone provide the next longest life. Tygon® formulations have a shorter life and Viton® generally provides the shortest life (less than 250 hours at 100 rpm).
Decrease system pressure. The life of tubing is significantly reduced at higher pressures, especially when using formulations such as C-FLEX and silicone which have low pressure ratings.
Reduce the occlusion to decrease the stress applied to the tubing every time it is compressed.
Avoid sharp tubing bends, especially near the pump head. When using Easy-Load® pump heads, run the tubing straight out of the pump head for at least 6-8″. This will keep the tubing centered over the rollers.
Create a maintenance program. Plan to move the piece of tubing that is over the rollers 6-8″ after a determined number of hours before it reaches its failure point.
View our selection of Masterflex pump tubing.