(1) Generation of welding cracks: When the weld design is unreasonable, such as improper design of the geometry and size of the weld, it may lead to the concentration of welding stress. Titanium alloy fittings are machined during the welding process, and this concentration of stress may trigger the generation of cracks. Cracks not only affect the overall strength of titanium alloy fittings, but also may cause them to break during use, seriously affecting their safety and service life. (2) Welding quality: Unreasonable weld design may lead to a decrease in welding quality. For example, welds that are too wide or too deep may lead to difficulties in temperature control during welding, which in turn affects the uniformity and integrity of the welding tissue. Insufficient or excessive filling of the weld may also lead to insufficient strength or defects in the welded joint. (3) Welding deformation: Titanium alloys are susceptible to heat during the welding process. If the weld design is unreasonable, it may lead to uneven heat action in the welding area, thereby triggering welding deformation. Welding deformation not only affects the dimensional accuracy and shape stability of titanium alloy parts, but also may increase the difficulty and cost of subsequent processing. (4) Mechanical properties: Unreasonable welding design of titanium alloy parts may change the local microstructure and chemical composition of titanium alloy parts, which in turn affects its mechanical properties. For example, the growth of abnormal grains may lead to changes in the hardness, strength, toughness and other properties of titanium alloys. In addition, the generation of internal stress and the phenomenon of hydrogen embrittlement may also lead to a decrease in the mechanical properties of titanium alloy parts. (5) Corrosion resistance: Unreasonable weld design of titanium alloy parts processing may cause defects or uneven organization of titanium alloy parts in welding areas, which may be more susceptible to erosion by corrosive media. Therefore, unreasonable weld design may reduce the corrosion resistance of titanium alloy parts, especially in harsh working environments. (6) Difficulty of operation: Unreasonable weld design of titanium alloy parts processing may increase the difficulty and complexity of welding operations. For example, overly complex weld shapes may require higher welding skills and longer welding times. This not only increases operating costs, but also may reduce welding quality and efficiency.