Titanium tube-tube sheet explosive welding forming involves the simultaneous multi-point explosive welding forming of rare metal thin-walled long pipe fittings and tube sheets and the microscopic analysis of the interface.
Titanium tube-tube sheet explosive welding has the following key technologies to be solved:
- (1) When titanium / steel is used for explosive welding, if the charge parameter control is not good, it is easy to cause high temperature of the interface and intermetallic compounds are generated at the interface, which will greatly reduce the heat transfer effect of the composite tube. Therefore, the explosive welding charge process of internal heat exchange titanium tube or zirconium tube is one of the keys to successful explosive welding.
- (2) Generally speaking, the wall thickness of the outer tube and inner tube of the composite tube is only 1 ~ 2mm. Ultra-thin metal composite materials, especially ultra-thin pipes, are prone to cracks or even break during the explosion welding process. Therefore, the detonation speed and the thickness of the charge must be accurately controlled.
- (3) The seawater corrosion-resistant high-efficiency composite tube must not only save rare metal materials, but also achieve efficient heat transfer. The key to efficient heat transfer is that the combined interface of the composite tube must be an excellent micro-wave interface, and the formation of the micro-wave interface Accurate optimization and design of charging parameters are required.
Explosive welding technology is used to realize the welding and forming of thin-walled titanium tubes and tube sheets, which not only improves production efficiency and reduces processing costs, but also improves the service life of heat exchangers and safe production, so it has important industrial application value. At the same time, through the optimization and precise control of test charge parameters, it is expected that an explosion welding molding workshop will be built inside the factory, which will greatly reduce production costs.
Using explosive welding forming process, compared with the above various tube expansion technologies, it has the following outstanding advantages:
- (1) Because explosive welding is a special type of pressure welding, it is possible to achieve welding between zirconium and titanium pipes and special-shaped metals such as steel that cannot be achieved by conventional welding and tube expansion methods;
- (2) Because the explosive welding interface belongs to the solid phase combination between atoms, the welding strength between the heat exchanger tube and the tube plate of the heat exchanger is high, which not only ensures the safety of the heat exchanger, but also greatly improves the heat exchanger Service life
- (3) Since explosive welding can achieve simultaneous detonation at multiple points, the productivity is high, and all tubes and tube sheets of a heat exchanger can be welded and formed at a time.