Titanium alloy for pumps, valves and pipes

Russian requirements for the operation of ship piping system are that structural materials should be guaranteed to have a service life of 8 ~ 9 years before the first docking repair, and the service life of the system should not be less than 15 years before complete replacement.  The requirement guarantees effective service of ships of all classes for 25 to 30 years.  Ships operate offshore, so their pumps, valves, pipes and other components face harsh ocean conditions.  

The pipeline system of Russian civil ship generally chooses M3C copper pipe and MH-5-1 copper alloy pipe according to the speed of water flow, and copper alloy is used for valves, pumps and heat exchangers.  If copper alloy material is used in vessel piping, it may have corrosion damage in the second year, and it is difficult to meet the requirements mentioned above.  It may be necessary to increase the thickness of the pipe to meet service requirements, and to increase the diameter of the pipe to support the flow rate.  The weight and cost of the ship's overall piping system has increased.

However, Russian warship pumps, valves, pipes and other more use of titanium materials.  The warship has been in service for a long time, and its service practice has proved that titanium alloy pipes, valves, pumps, heat exchangers and other products are highly resistant to seawater corrosion and have a long service life.  If all titanium materials are used to manufacture the ship water intake system, the service life of the system can be significantly prolonged and the service reliability can be improved.  

The U.S. Navy uses titanium alloy piping systems on ships.  Compared with the traditional copper-nickel alloy pipeline, titanium alloy has strong corrosion resistance, even in the high-speed flow of seawater (flow rate of 13m/s), it will not be eroded by seawater, especially suitable for the working medium of moving seawater, high flow rate, high pressure pipeline.  As a result, the titanium alloy's high corrosion resistance allows for thinner pipe designs, smaller pipe diameters, less space for ships, more flexibility in placement, and lower maintenance costs while maintaining the same seawater flow.  In addition, titanium alloy has a low density, about half that of copper-nickel alloy, and it produces a low mass pipe, which reduces the amount of equipment needed to support the pipe.  Ships are less loaded and consume less fuel.