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How to expand heat exchanger tubes efficiently

Product Announcement from Haskel International LLC

Expand heat exchanger tubes into tube sheets through the direct application of high internal hydraulic pressure. Direct Hydraulic expansion with pure water produces clean joints. Minimize stress, crevice corrosion, and metallurgical changes, avoid forcing lubricant into the tube surface & prevent surface flaking or spalling inside the tube.

HydroSwage® by Haskel offers a wide range of equipment designed to expand heat exchanger tubes. HydroSwage® tube expansion applications are used in Power Generation, Nuclear Power Generation, Nuclear Energy, Heat Exchanger Manufacturing, Heating and Air Conditioning, Sanitary Shell and Tube Heat Exchangers, Petro-Chemical, Pulp and Paper Mills, Pharmaceutical, Steam Condensers, Pressure Vessels, and Hydro-Forming.

Proven to Provide Years of Dependable Service!

Our systems are proven to provide years of dependable service. Customers such as ENSA, Ansaldo, Doosan Heavy Industries and B&W Canada, all use the HydroSwage® Mark IV systems that have been in operation close too, if not 20 years!

How Hydroswage works

The HydroSwage® System is innovative and designed to hydraulically expand heat exchanger tubes into tube sheets through the direct application of high internal hydraulic pressure within an established expansion zone. Direct Hydraulic expansion with pure water produces clean joints. Lubricant is not forced into the tube surface, and there is no surface flaking or spalling inside the tube.

A Tube-Loc TM drawbar quickly positions and sets the tube into the tube sheet prior to HydroSwage® expansion. It is also used to set tubes prior to welding, and to flare boiler tubes.

Water pressure from an air driven pumping system intensified to the desired high pressure. It is transmitted through a small bore, flexible high pressure tube to a lightweight hand-held mandrel holder. A mandrel, which latches into the mandrel holder, directs the pressure to the inside diameter of the tube ad is held within an accurately prescribed pressure zone. Pressure is contained within the expanding tube by a soft elastic seal which is supported by a patented elastic backup and an expanding segmented steel ring. Pressure is applied over the full length of the joint in one step. The pressure zone is accurately adjusted which reduces the damaging crevices at the edges of the tube sheet. Stress, crevice corrosion, and metallurgical changes are thus minimized.

A smooth transition from expanded to un-expanded areas, along with no change in tube material properties, greatly reduces strain hardening, tube fatigue and stress induced corrosion cracking. Tube wall thickness and tube length change is minimal. Before contact is made with the tube sheet, a small reduction in tube wall thickness and length occurs because a constant volume of tube material is expanded to a larger diameter. However, no change occurs during the high pressure swaging, eliminating the shear strain and loss of seal between tube and sheet that is a characteristic of roller expanding.

For more information visit our website or e mail us with your inquiries