Optinova, one of the largest manufactures of intravenous catheters has installed “in line” leak detection equipment into their production process for catheter tube manufacturing. The thin wall tubing is used for nutrition and blood transfusion delivery systems. Optinova called in Adixen Scandinavia (an Alcatel Company), a specialist leak detection company based in Sweden, to assist them with the challenging task of developing a system to identify pinholes in the tubing while it is being formed. Installing in line leak detection would reap huge benefits for Optinova by eliminating secondary after process testing, or testing after more work had been put into the tube.
The approach that was discussed and agreed upon by both parties was to have the tube formed in a cloud of diluted hydrogen tracer gas* and then passed through a specifically designed accumulation chamber at line speed. Minor defects, pinholes in the tube, would be identified by a detector that continuously monitors the chamber for the presence of hydrogen leaking from the tube into the chamber. A signal would be given from the detector to the tube manufacturing process if a leak was detected, the line would be stopped and the faulty section cut and removed. The process would then continue.
The detector that was chosen was the high sensitive hydrogen leak detector – H2000 PLUS. The H2000 PLUS has a sensor (Gas-FET) that is specific to hydrogen, has high leak rate sensitivity (5X10-7 cc/sec), requires no schedule maintenance and is competitively priced to meet most budgets.
A prototype test system was designed and delivered to Optinova by an Adixen application specialist and set up to run a few tests under the direction of Mr Roger Andersson, manager of development and engineering at Optinova. He said: “The test results showed that the system worked brilliantly.”
Adixen were tasked by Optinova to build a final engineered solution based on the initial prototype findings and to repeat the testing over a longer period of time. The new system was installed onto one of the tube manufacturing lines and run continuously. Mr Andersson said: “Adixen did a great job. Of all the equipment we have purchased in our manufacturing process the tube leak tester was the one we have had to do the least adjustments to, which is really high praise.” Optinova have now invested in seven tube leak test systems from Adixen, one for each tube production line, resulting in quality tube production at line speeds.
*Diluted hydrogen as a tracer gas (95% nitrogen, 5% hydrogen) is a non-flammable, inexpensive, readily available and environmentally friendly.