Over the years Miller Mechanical has built various heat exchangers both horizontal and vertical; removable tube bundles and fixed bundles; floating and fixed tube sheets; and with and without expansion joints.  Heat exchangers, with only a couple of hundred tubes up to a re-boiler with almost 2000 tubes, have been fabricated and shipped from our facilities.  Materials are chosen based on the contents, temperatures and a host of other factors that must be considered in order to arrive at the best overall configuration for that application.