The initial point for the preparation of the program is the technology, respectively plotting -computer. By using suitable software and based on goal-parameters, such as ingot size, final dimension of the forging and penetration depth, the pass sequences are being generated either manual or automatic.

The so constructed forging program will then be stored on the control computer, which functions as a link between the operation desk and the press control. It can be directly called-in by the press operator.

On the right-side control-desk-monitor the pass sequence data are being displayed in tabular form, while on the left-side main-monitor, the most important press-data is still visible for the press operator.

With the use of a special tracer, the press operator is able to call-in each individual pass and to jump on any given spot of the pass plan. The current pass plan data, such as size, speed and swing angle will be taken over by the control system and can be executed by activating the master switch. Besides the fully integrated operation between the forging press and the manipulator, it is also possible to perform the forging operation in a semi-automatic or manual mode. When using these modes, the plan data are also taken over by the press control, from the forging program. In this case, however, the press operator does maintain control over the forging process at any time. This has proven to be advantageous, especially when forging heavy ingots, where handing problems are not unusual.

LOGGING

The core-data of the logging are the stroke-data that are being submitted to the control computer by the press control(see picture above) Each individual stroke, carried out by the forging press will be noted in a stroke-record that is being appointed to each forged part. This stroke record contains the following data.

• Time stamp
• Dimensions (comparison of target values and actual values)
• Accurate position of manipulator (comparison of target values and actual values)
• Swing angle (comparison of target values and actual values)
• Forging pressure
• Temperature (pyrometer)

Furthermore, a lot of additional organisational data are being noted, that are needed for a later analysis of the stroke-records. However, it is only possible to make a correct statement about the quality of the forging process, if one is able to summarise the numerous stroke-date to passes, again, that can be worked up by a filter. For this special cause, an analysing-software has been installed on the plotting computer. Its function is explained in picture

Documentation and Evaluation

The logging and the analysis of the stroke-data is always possible, independent of whether the forging process has been conducted with the program or not.

First, the stroke-record will be cleared of any insignificant notes, in order to use the remaining information to calculate the passes, that are being characterised by the mean values of dimensions, manipulator action steps and swing angle. For this step, the analysis program does need additional information about the forging process. This information has to be contributed by the operator. If the forging process is performed with the program, it is possible to conduct a comparison between target values and actual values, due to the goal-parameter of the program.

The result will be presented very easily understandable in a deviation record. The deviations from the target values for dimensions, manipulator action steps and angle are marked with number-1. The error tolerances for each parameter are being stored in the relevant forging program.

Due to the transparent structure of the logging system, without much effort the data analysis can be modified for numerous other special tasks.

CONCLUSION

Since applying the Program-Forging-Process at the beginning of 1999, the number of forgings for the power generation industry, that had soundness problems has been reduced to virtually zero.