A tubular heat exchanger has at least one pair of dimples which are extruded into at least one tube of the heat exchanger by deforming the tube wall inwardly. For More details visit: http://www.patentstorm.us/patents/6945320.html

A tubular heat exchanger comprises tubes mounted between upper and lower plates employing a heat- and acid-sensitive resin at the upper plate. To prevent a fluid medium from corroding the resin, a further plate comprising an acid- and heat-resistant material is provided separating the medium from the resin, and a cooling medium is flowed through the separating space For more details visit: http://www.freepatentsonline.com/4224982.html