Teflon Tubing Is a Powerful Tool for All Types of Laboratory Analysis Using an Autoanalyzer
When Perstorp bought Alpkem way back when, they radically changed the platform and created the Expanded Range (ER) detector which to this day is arguably the best autoanalyzer detector ever made. In combination, they added their type of tubing and mixing blocks which together instantly created a very powerful tool for all types of laboratory analysis using an autoanalyzer. They primarily used Teflon and flanged fittings as well as acrylic and PEEK mixing blocks. Over the years since Alpkem was bought by OI Analytical the original configuration of tubing that made the platform so powerful has degraded considerably.
Most of these flow systems now have an inconsistent mixture of tubing such as EVA, PE and PEEK as well as a variety of IDs and ferrules instead of flanged fittings. This creates a series of problems from surging due to inconsistent flow interruptions, potential for easy blockage and chemical degradation and buildup on the tubing from reagents. For instance, PEEK tubing when used with a hot heater gets very brittle over time and ends up leaking hot reagents all over including the on the heater electronics. Needless to say, this is expensive and leads to an expensive replacement of the heater. But Teflon has a higher melting point, is more inert and is more lubricous. In fact, PEEK can be dissolved with sulfuric acid which is commonly used in Phosphate and TKN analysis.
Just as Perstorp initially configured these systems, EZkem has been placing Teflon tubing on Alpkem and OI Analytical heaters when we repair them and perform PMs on flow systems. Not only have we not seen any leaks occur, but we also see much better flow dynamics and a greater resistance to chemical buildup from reagents. Similarly, when we have rebuilt Alpkem and OI Analytical heaters with Teflon customers have seen dramatically improved flow dynamics on low level analysis cartridges such as phosphate or ammonia.
These improvements are the greatest when all the tubing on the cartridge (as well as the heater) is replaced with flanged Teflon tubing. Teflon tubing lasts longer, does not need ferrules when used with a flanged fitting, and when the entire system is configured with the same ID Teflon the flow dynamics are dramatically improved and produce lower level results. Please contact us if you have any questions or need more details.