Due to its excellent corrosion resistance, titanium is widely used in petroleum, chemical, seawater desalination, ocean development, and other related engineering fields. However, the cost of titanium is very high, especially for large-scale equipment, and this problem is particularly prominent. Titanium clad plates not only have excellent corrosion resistance to titanium but also greatly reduce manufacturing costs, so titanium composite plates are often used in the above fields. An economical and quality-assured alternative to planks. Among them, heat exchangers, condensers, and other titanium clad plate tube sheet welded structures are relatively common structural forms in the above-mentioned engineering fields. Therefore, it is of great significance to discuss the welding process of titanium clad plate tube plate to promote the promotion of titanium clad plate and to ensure the welding quality of the titanium clad plate tube plate structure.
Weldability Analysis of Titanium Composite Plate
First of all, titanium starts to absorb hydrogen at 250°C, oxygen at 400°C, and nitrogen at 600°C, and the ability to absorb hydrogen, oxygen and nitrogen increases significantly as the temperature increases. Contamination by impurities such as gases can cause embrittlement of welded joints. Therefore, as long as the surface temperature of the titanium material reaches above 250°C, high-purity argon should be used for protection. Secondly, titanium is very sensitive to oil, dust, iron filings, etc. Therefore, the workpiece, welding wire, and auxiliary tooling must be carefully scrubbed with acetone or alcohol before welding, and workers must wear clean gloves for welding operations. The qualified weld seam and heat-affected zone color of titanium material should be silvery white or light yellow. For titanium composite plates, the linear expansion coefficient and thermal conductivity of steel are 1.6 times and 5.5 times that of titanium, respectively, which causes the welded joint to shrink inconsistently during the cooling process and form a large internal stress, thus leading to weld cracking, Therefore, when the titanium clad plate is welded, the base carbon steel and the clad titanium material cannot be fused with each other, that is, there cannot be a "transition layer".
To sum up, the key points of tube-sheet welding of titanium composite plate mainly lie in:
(1) Design protective tooling according to the product structure;
(2) Formulate a reasonable groove form and welding process to ensure that the base carbon steel will not be melted and cause carbon and iron ions to pollute the titanium when welding the cladding.
Baoji Taicheng Clad Metal Materials Co., Ltd is a titanium clad tube sheets manufacturer, which can provide high-quality products and services for overseas buyers. Our metal composite sheets are sold to various countries around the world, and we have a large number of long-term cooperative friends. High-quality products and services are the basis for our recognition. If you are interested in our products, welcome to consult and cooperate!
