#102 Extended service life and reduced maintenance in isolation application.  Problem: At a gulf-coast chemical plant, three cooling tower pumps were isolated employing high performance butterfly valves. There were 42-inch lined valves (Jamesbury 8000) on the suction side and 36-inch lined ball valves (Norris R-3000) on the discharge side. After a relatively short time in service, degrading lining and swelling rubber seals kept the valves from closing properly.  Solution: The local Tufline Sales Engineer and the Tufline Distributor Representative were called in to analyze the situation and offer recommendations. They proposed the use of Tufline high-performance butterfly valves. They assured the facility managers that the unique patented and protected seat would provide tight shutoff, through numerous cycles, for a greatly extended period of time. The seat is simple and symmetrical. Its symmetry assures mistake-proof maintenance. It always goes in right. Its simplicity of design means there are no springs to break, no O-rings to swell, and no hoops to erode. The unique design also protects the seat from abrasion and corrosion, further extending service life.  Critical Timing With local distributor support and inventory, not only was Tufline able to meet their demanding delivery requirements, but the valves were also modified in that short time span to match the existing face-to-face dimensions, all at an attractively competitive price.  Result: The first plus was that the lighter weight Tufline valves were easier and more economical to install. The most important payoff for the processor has been greatly extended long-term reliability. Maintenance (when it is infrequently required) is also easy and economical. Index of all performance report case histories.