| 摘要 |
A process for applying a weld overlay to a tube with a single pass of a weld head. An inverter-type alternating current pulsed power source, composed of a primary inverter and a secondary inverter, is used to control the melting rate of welding wire during welding of the overlay to the tube. The primary inverter controls the value of output current, and the second inverter changes the polarity of output current between electrode negative. For a given welding current, the wire melting rate increases significantly as the electrode negative ratio increases, and this makes a relatively high welding speed attainable. Increasing the electrode negative ratio at a fixed, predetermined wire feed rate decreases the weld penetration depth, which correspondingly lowers the dilution rate and results in a smooth and narrow welding bead.
|
