高稳定性电弧喷涂刚性送丝机的设计

目的解决传统电弧喷涂送丝机的局限性,特别是柔性送丝结构存在的送丝速率低、送丝波动大等问题。方法设计了刚性送丝结构,进而成功研制了高稳定性电弧喷涂刚性送丝机,并通过送丝速率测试、喷涂电流测试及喷涂焰流观察等对比性试验,验证了设计的有效性和可行性。结果在无喷涂状态下,传统柔性送丝机和文中研制的刚性送丝机的送丝速率均随送丝电压的增大而增大,且刚性送丝速率呈近似线性变化趋势,而柔性送丝速率具有一定随机性。在相同送丝电压下,刚性送丝的速率高于柔性送丝,即具有更小的送丝阻力;且刚性送丝机两侧丝材送进平均速率的同步误差均小于3%,而柔性送丝机的同步误差为5%左右,说明刚性送丝机具有较好的送丝同步性。同时,柔性送丝机的送丝速率波动率为10%左右,而刚性送丝机的仅为2%左右,说明刚性送丝机在无喷涂状态下具有优异的送丝稳定性。在喷涂状态下,刚性送丝机和柔性送丝机的喷涂电流波动率分别为4.76%和29.36%,且刚性送丝机的喷涂焰流比柔性送丝机的更加集中稳定,说明刚性送丝机在喷涂状态下也能保持良好的送丝稳定性。结论刚性送丝结构可以有效减小送丝机的送丝阻力并保证两侧丝材送进的同步性,使送丝过程具有更高的稳定性。

Design of High Stability Rigid Wire Feeder for Arc Spraying

The work aims to solve limitations of traditional arc spraying wire feeder, especially problems in flexible wire feeder including low wire feeding rate and great feeding fluctuation. A rigid wire feeding structure was designed, and a high stability arc spraying rigid wire feeder was developed successfully. Furthermore, effectiveness and feasibility of the design were verified by such comparative experiments as wire feeding rate test, spraying current test and spray flame flow observation. In the absence of spraying, the wire feeding rate of both traditional flexible wire feeder and the rigid wire feeder developed in this paper increased with the wire feeding voltage, and rigid wire feeding rate tended to increase linearly while flexible wire feeding rate was of certain randomness. At the same wire feeding voltage, the rigid wire feeder exhibited higher feeding rate, i.e., smaller wire feeding resistance. Furthermore, synchronous errors of average wire feeding rate on both sides of the rigid wire feeder were less than 3% while that of the flexible wire feeder was nearly 5%, indicating that the rigid wire feeder had better wire synchronization. Meanwhile, fluctuation ratio of wire feeding rate of the flexible wire feeder was about 10% while that of rigid wire feeder was only about 2%, showing that the rigid wire feeder had excellent wire feeding stability in the absence of spraying. Under spraying condition, spraying current fluctuation ratio of the rigid wire feeder and flexible wire feeder was 4.76% and 29.36%, respectively. Spraying flame flow of the rigid wire feeder was more concentrated and stable than the flexible wire feeder, showing that the rigid wire feeder could maintain excellent wire feeding stability under spraying condition. Therefore, the rigid wire feeding structure can effectively reduce wire feeding resistance of wire feeder, and guarantee synchronization of wire feeding on both sides, and improve stability of the wire feeding process.