Aluminum tube bending has helped the military put out the oil refinery fires during the Iraq war. 45 degree elbows formed by mandrel tube bending connect straight tube sections across the desert to transport water.
Each aluminum section, either straight or bent, has grooves machined into the ends of the tube. In the case of the bent aluminum sections, the machining is done after the bending. The grooves are part of a special coupling.
Another special requirement is to pack the curved sections using green lumber because the tube is annealed after being bent. The green lumber does not ignite from the heat of the annealing process.
