Weighing the advantages of tubing versus pipe

Tube bending improves fluid-flow characteristics by creating compact systems with smooth directional changes. Conversely, the 45 or 90° elbows used in piping systems frequently increase turbulence. The demands placed on today's fluid systems are much tougher than they were a decade ago. Leaks that were once considered nuisances are now classified as fugitive emissions and hazardous spills, problems that can shut down plants. Modern processes are pushing pressure, flow, and temperature requirements to new heights every day, yet the basic concepts of connecting pipe have not changed much over the years. In fact, the integrity of most piping systems depends on sealing and fastening methods developed nearly a century ago. Tubing provides one solution to tougher regulations and increasing stresses on fluid systems. Tubing and pipe both carry fluids in industrial applications, but tubing offers several advantages over pipe. Compared with pipe, tubing is generally easier to install and maintain, costs less, and performs better. First of all, tube fittings are designed not to leak, even under rugged operating conditions because they have mechanical, metal-to-metal seals. Tightening fitting nuts cold-swages ferrules onto the tubing. On the other hand, threaded-pipe connections typically require heavy equipment to cut threads and pipe dope or TFE tape to minimize leakage. In addition, the greater flexibility of tubing often means systems with fewer connections. This equates to fewer potential leak points and lower costs. Tubing is readily available in diameters up to 2 in. with a variety of wall thicknesses and materials to meet the toughest application demands. It's important to note that tubing and pipe are sized differently. A 1-in. pipe, for instance, has a 1-in. nominal bore, while a 1-in. tube has a nominal outside diameter of 1 in. Another advantage of tubing is that it can generally be installed faster than pipe. Tubing