Paton Welding Institute, Kiev, Ukraine
The programMODUL is intended for preliminary evaluation by computing experiments of technological parameters (velocity of the wire feeding, the power source operating levels of currents and voltages etc.) for the arc welding by the modulated current with melting electrode.
The mathematical model is based on the equations set for description of changes in a time of the working wire length taking into account its feeding by the external mechanism and a diminution of its length due to the separation of melted drops. The wire melting description includes heating by the electric arc (part of energy U*I), and Joule heating.
Data-ins for computing are the following values:
- Radius of the wire;
- Length of working gap;
- Starting length of the wire on the beginning of process, if it is equal to length of working gap, the process begins with a short-circuit;
- The relation of diameters of the drop and wire on which happens the drop departure;
- Current and voltage of the power supply for the short-circuit mode.
During computing experiment diagrams of the current and voltage, distribution of temperature on length of the wire, velocities of melting, its averaged value and external feeding graphically are mapped.
The complicated form of the modulated welding current approximates by four square waves of various duration.Thus, the modulation in the program is determined by the following parameters:
- 4 temporary intervals (3 for a mode IMPULSE and 1 for PAUSE);
- 4 levels of working currents;
- 4 levels of operation voltage;
- 2 velocities of the wire feeding;
- 2 levels of efficiency of the melting process as a result the environmental conditions (sub-merged mode etc.);
The program allows to simulate a mode of welding with short-circuits, which occurs in that case, when the wire length becomes equal to length of the working gap. In that case, when the duration of the short-circuit mode exceeds some time, assigned by the user, the computing experiment is finished.
The programMODULwas prepared for work on personal computers, compatible with IBM PC/AT I80286 and better with MS DOS versions higher 2.0, or it analogies (DR DOS, PC DOS etc.), with the minimum of the free memory is about 300 KB. No problems with Windows 9x occurs also.
Modification and adaptation of this software can be made on request