To prevent failure during lengthy use, tube life should be monitored and a preventive maintenance program enacted.
Single-use tubing can be used for the length of a biopharmaceutical product campaign and changed when a new product is to be manufactured. To prevent failure during lengthy use, tube life should be monitored and a preventive maintenance program enacted. Pharmaceutical Technology spoke with Gregg E. Johnson, global senior product manager for the Cole-Parmer peristaltic pump product lines, about these concerns.
PharmTech: How long does single-use tubing typically last?
Johnson (Cole-Parmer): The lifespan for tubing is dependent upon pumping conditions- speed, pressure, fluid, and fluid temperature. Some new biopharm formulations of silicone tubing can last 200 to more than 1000 hours. For the Pharmed materials (made from a thermoplastic elastomer), life expectancy can be several thousands of hours.
PharmTech: How does a company go about monitoring the tube life?
Johnson (Cole-Parmer): In our testing lab, we monitor the tube life by recording the hours between failure. Once we have a pattern, we can set up preventative maintenance based on the specific installation. Each one is different due to different fluid, piping systems, and other devices in the fluid path.
PharmTech: What are some rules of thumb for performing preventive maintenance?
Johnson (Cole-Parmer): Preventative maintenance (PM) and the frequency at which it is performed is determined by the pump operator. A simple recommendation is to review the tube-life data provided by the pump manufacturer. A good place to start may be at 75 to 80% of the manufacturer’s data until a reliable pattern is defined. Each installation is different. Once this pattern is established, and longer PM cycles are desired, the operator can elect to extend the cycles to fit needs.
PharmTech: How can tube life be extended by moving the tubing to a new position?
Johnson (Cole-Parmer): If an operator is performing a long-term campaign and is concerned about tube life, he or she can extend the run and prevent the possibility of tubing failure by moving the tubing to a new position. This is accomplished by setting the system up with excess tubing on the discharge (outlet) of the pump. Once the campaign is running, the operator can, on a periodic basis-once a week or once a month-pause the pump rotation, open the pump head, and slide a section of unused tubing (from the excess at the start of the campaign) and move the used section from the pump head to the suction (inlet) side. The pump is then closed and restarted.