Research On The Equipment Of The Plasma Arc Powder Surfacing For Roller

Roll's surface is very easy to be damaged because of the complex and poor working condition and then result in its failure. The technology of surface repairing and heat treatment has become the main development direction and approach to extend roll's life and reduce production cost. Practice has shown that the plasma arc powder surfacing is one of the effective ways to repair the roll and has become an important measure for our country's rolled steal enterprises to improve the repair quality, shorten the repair cycle and improve the efficiency. Plasma arc powder surfacing is a welding process which use the plasma arc as the heat source, the alloy powder as the filler material, then clad the filler metal onto the base surface. Its goal is to make the surface of the materials or the components get the deposited layer with the special use properties of bearing wear, corrosion, heat, oxidation and so on. This welding process has the advantages of low dilution rate, good forming, stable process, high automation degree and so on.A plasma arc powder surfacing equipment for roll is developed respond to the actual production needs. PLC is the control core of the device, supplemented by the touch screen to set and modify the surfacing parameters and display the state of parameters during the surfacing process. In order to make the welding torch have the capabilities of oscillating quickly and positioning accurately to ensure and improve the welding quality, a servo system is used instead of the stepper drive system commonly used in the oscillating system. The welding process of this device is completed by three movements of torch oscillating, roll rotation and torch transfer. The torch oscillating is implemented through oscillating mechanism driven by servo system controlled by PLC. The roll rotation is completed by the lathe motor controlled by inverter controlled by PLC. And the torch transfer is achieved by the stepper motor controlled by PLC.The device has two surfacing methods that are circumferential welding and spiral welding and the main difference is the different moving modes of the welding torch. The welding torch will make a lane change at the end of each lap along the roller axis during the circumferential welding. However, the torch movement is continuous when the spiral welding is adopted. The setting of the two surfacing methods increases the choice and flexibility in the actual operation and, to some extent, provides a reference for the development and improvement of the same type welding equipment.