 cabinet 0  cabinet 1 The control system provides for:
- control of actuators and mechanisms of welding machine both in manual and semiautomatic operation modes;
- control of process cycle in accordance with welding machine cycle pattern being programmed in dependence of moving frame travel with continuos or pulsating flashing;
- tolerance testing and welding cycle parameter registration with issue of certificate for welded butt indicating its useability or defects.
The control system of welding machine includes the following components:
- control cabinet;
- control panel.
The control system is designed on base of equipment of SIEMENS Company:
- control unit SIMATIC S7-300 (processing module of CPU-314-2 PtP type with supplementary input/output modules);
- industrial computer (notebook) with LCD-screen connected with the control unit via communication MPI-link.
Two-line LC-display of OP 3 type of SIEMENS Company is installed on the control panel located directly on the welding machine; the data on performance of process cycle and on position of moving frame of welding machine is displayed on it. The control of welding machine devices and mechanisms in setting-up operation mode is also performed from the keyboard of OP 3 display.
The analog resistive measuring system of MLO-ROT type of FESTO Company with 100-mm range is used as the sensor of welding machine moving frame position.
The pressure sensor of HM-17 type of BOSCH-REXROTH Company is used as the pressure sensor in the working ends of travel and upset cylinders.
Electrohydraulic tracking valve of BOSCH-REXROTH Company is used as an actuator driving the travel of moving frame.
Direct control of welding machine is performed by control unit of SIMATIC S7-300 type in accordance with the software stored in its memory and following the program of welding process transferred to it via communication link from the industrial computer.
The industrial computer is designed for programming of welding process and features of tolerance testing of main parameters of the welding process, diagnostics and visualization of status of sensors, actuators and mechanisms of the welding machine.
The programming, control, diagnostics and visualization system is implemented as intuitively obvious window-type menu.
From the main menu (Fig. 1) it is possible to open the following windows:
- "Shift staff selection" window;
- "Machine status" window;
- "Program input" window;
- "Weld archive" working window;
- "Help" window.
In the "Shift staff selection" window (Fig. 2) names of foreman and welder, butt code and number, and process program number with the modes of future welding are selected. After all the specified parameters are entered the shift data shall be confirmed. After the shift is finished press the button of shift end, and only after that the shift report can be printed (Fig. 3).
In the "Machine status" window (Fig. 4) the welding machine with its appropriate sensors and actuators is shown schematically. The activated status of sensors and actuators is shown highlighted in green colour with corresponding filling of rod and head ends of cylinders with green colour. This window displays also some main parameters of the welding process: welding path and time, welding current and voltage, etc. From this window it is possible to switch to the window of control of initial position of mechanisms and sensors taking part in displaying of initial status of welding machine, sensors, actuators and mechanisms of hydraulic aggregate, and to the window of real-time browsing of welding process.
In the "Program input" window (Fig. 5) all the technical parameters of welding process are set. The following parameters are specified: program number and number of flashing areas, path of moving frame for each area, voltage of welding transformer primary winding, forward and backward speed, option of velocity compensator and type of control (by current or by power), parameters of compensator, and thermal treatment is activated or cancelled. The change of program parameters is password protected, i.e., the person not knowing the password will not be able to change them.
In the "Weld archive" working window the following options are available: selection of weld by date and viewing of oscillogram of main and secondary welding parameters (Fig. 6), data of certificates (Fig. 7), as well as printing of selected data. The user has a wide range of possibilities viewing the oscillogram: selection of any area, scaling by any of the axes, table presentation of process data along with its graphical presentation, etc.
The additional parameters can be recorded: control voltage of tracking hydraulic valve, specified and actual position of moving frame. These additional parameters are necessary for quality analysis of operation of travel electrohydraulic drive. The operation program of control unit includes "Test" mode; in case this mode is activated the reciprocal (back-and-forth) travel of moving frame is performed with registration of all the parameters into the archive. This mode permits also to estimate the speed and frequency parameters of electrohydraulic drive of the moving frame travel.
The "Help" window displays the detailed information on operation with programming system, on tolerance testing, diagnostics and visualization.
In case there is no connection with the control unit, the communication error is displayed in the main menu window; press the "Set connection" button, and the connection will be set in several seconds.
The implementation of the control system on base of high-reliable equipment of SIEMENS Company and development of the software providing for highly user friendly interface between control devices and operating personnel has allowed to create the presented control system for machines of butt induction rail welding on the highest world first-class level; the control systems for a wide range of equipment of contact electric welding can be arranged on base of this system.
 Pic 0  Pic 1  Pic 2  Pic 3  Pic 4  Pic 5  Pic 6 |
