The development of high technologies such as information technology and optical-mechanical-mechanical integration technologies has effectively promoted the technological progress of the rubber industry. The use of high technology to transform the traditional rubber industry and the development of production technology to high technology is the only way to build a strong rubber industry. At present, the rubber industry is still an industry with more manual operations. In particular, tires, rubber shoes and other components have more than a dozen processes, and the labor intensity and low production efficiency seriously affect the development of the rubber industry. . The industrialized countries all focus on the molding process of rubber products, and have achieved significant development in automated production through computer technology, optical-mechanical-electrical integration technology, and robotics technology.
2 continuous vulcanization production process control
2.1 Vulcanization molding
Vulcanization molding is an important process for rubber processing. In order to improve the performance of rubber products, a series of processing steps are required for the production of raw rubber. Under certain conditions, the raw rubber in the rubber compound reacts with the vulcanizing agent to form a cross-linked macromolecular structure. Three-dimensional network structure of macromolecules, so that the rubber material has high strength, high elasticity, high wear resistance, corrosion resistance and other excellent performance. This process is called rubber vulcanization. The vulcanization process is generally divided into four stages, induction-pre-sulfur-normal vulcanization-oversulfur. In order to achieve this reaction, it is necessary to apply additional energy to reach a certain vulcanization temperature, and then let the rubber insulation complete the vulcanization reaction within the vulcanization temperature range.
2.2 Continuous curing process control
(1) Microwave rubber vulcanization equipment and production process. The basic process for the vulcanization of rubber products with rubber skeletons is: the molded products extruded from the extruder are conveyed through a conveyor belt or a roller conveyor and enter a microwave vulcanization device where the rubber is rapidly heated to the vulcanization temperature and then enters the secondary The vulcanized hot air tank insulation completes the foaming and vulcanization process of the product. The composition of the microwave rubber vulcanization production line consists of pay-off equipment, extruders, high-temperature setting equipment, microwave vulcanization equipment, hot-air vulcanization equipment, cooling sections, traction machines, cutting machines, and drilling machines.
(2) process transmission control. After the release device and the release tension are controlled, the preformed roller carrier passes through and heats, and the rubber material extruded by the extruder covers the jacket; the wire covering the rubber jacket enters the production line main-speed traction device and is subjected to high-temperature vulcanization. The frequency converter controls the production speed per minute, and then goes through the caterpillar assisted traction into the post-processing stage. In the core gold breaking and forming device, the tensile force is sensed as tension feedback via the tension frame, the speed is given by the main speed, and the constant speed and constant tension are sent. The line is controlled by the meter counter after cutting; in the whole production line, the main traction and auxiliary traction control systems work in the speed mode: including high-temperature processing, microwave vulcanization, and post-heating speed series synchronization; and require all levels can be fine-tuned and after Level synchronization adjustment. The strip discharge and forming control system works in a constant torque mode; the torque fluctuations caused in the speed mode are controlled by the torque control system and cooperate with each other to ensure constant speed and tension.
3 Inverter Synchronous Drive System
3.1 Synchronous drive system principle design
In the whole production line, the main traction and auxiliary traction control systems work in the speed mode: including high-temperature processing, microwave vulcanization, and post-heating speed series synchronization; and require that all levels can be fine-tuned and synchronized at the later stage, speed synchronization solutions as shown in Figure 1 shows.
Configuration design: 3 5.7-inch 1711STNHITECH Hitech touch screen; 1 DVP12SA Delta PLC; 4 VFD007B43A inverters.
This configuration only involves synchronization of four inverters in the production line. The entire production line controls three man-machines, four inverters and four frequency converters to control the first-class water line, and is divided into four sections. The project mainly uses the convenience of Delta communications and reads the frequency of the inverter at any time and any place by means of communication. As long as the frequency of one of the inverters is found to change, the following inverters will change according to a certain proportion, so as to handle the synchronization of the four-step speed to control the tension, and the three man-machines form the master-slave and are installed at each job. In paragraphs, each human-machine interface is exactly the same. When operating, it can be operated on any touch screen to facilitate the operation of workers.
The original customers used to use the man-machine UP / DOWN way to fine-tune, but the customer is not more convenient to use, used four-way synchronization controller, but the customer's requirements, need to set the frequency, the proportion of the relationship between the man-machine , However, this time the man-machine dealer selected HITECH man-machine, and its HITECH man-machine only has two communication ports, and its communication port has been occupied, it can not use the synchronous controller.
3.2 Synchronization Control Requirements Analysis
Four frequency converters, when one of the frequency converters has been changed (by analog changes, or the main frequency, the ratio given) have been changed, then the subsequent several frequency converters will automatically correct the frequency to ensure synchronization. Moreover, when there are more than two inverters at the same time through the analog fine-tuning or through the man-machine to change the proportion, the main speed, then the previous one prevail, the subsequent number of frequency values ​​must be modified to shield off, for example, there are two sites The operator also modifies the analog frequencies of the second and third inverters to fine-tune the frequency. The frequency modification value is based on the second station.
3.3 Pipeline Drive Relationship Design
(1) Inverter frequency setting source: Inverter main frequency (communication setting) +0--10V analog quantity superposition.
(2) Synchronous relationship of the frequency converter: The first frequency value = the main speed setting (by man-machine setting) + the first analog auxiliary frequency setting (set by analog quantity).
(3) The second frequency value = the first frequency value * the ratio of one (by man-machine setting) + the second set of analog quantity of auxiliary frequency (set by analog).
(4) The third frequency value = the second frequency value * Proportional two (by man-machine setting) + The third analog sub-frequency setting (by analog setting)
(5) The fourth frequency value = the third frequency value * the ratio of three (through man-machine settings) + the fourth set of analog auxiliary frequencies (set by analog).
3.4 Programming difficulties
The frequency value is the main frequency and analog auxiliary frequency setting. It is not known when the analog auxiliary frequency changes in the field. Therefore, when writing the program, the frequency must be read every moment to understand the frequency change of the frequency converter, and the frequency After reading well, according to the frequency change calculated according to the ratio, the calculated frequency value is automatically written to the corresponding inverter by communication. Because it is the frequency of reading at every moment, and there are two sources of frequency given, the difficulty lies in when to write the comparative value to the register, and then use this frequency value to compare with the frequency of reading as a reference value. . Originally wanted to use A/D, D/A analog interface signals, so that although the writing process is simpler, but because the on-site production line is too long (five or sixty meters long), and the fine-tuned analog quantity must be close to each station The current status of the wiring is difficult. In such a long line, the analog signal will have a lot of attenuation and interference, and the communication will be relatively better. Therefore, the use of a completely communication method to solve the customer's synchronization requirements is a relative requirement. Compilation will be more complicated, especially when reference is made to comparative values, and how to screen several subsequent frequency changes.
3.5 programming ideas
(1) When the analog quantity changes. After reading the frequency of all inverters (d190-d197), the frequency changes (when the analog quantity changes), and this frequency change lasts for two seconds, set m10, and trigger m1-m3, calculate the corresponding frequency (frequency value Put it to d2000--d2007), and then start writing frequency, after writing, timing 100 ms, then start reading frequency again, read it, trigger m16, write down the value (D590-d597), and then start reading again and again frequency.
(2) When the proportional value changes (m100m101m102m103) First main speed is modified (m100 set), set m10, first write the frequency of the first inverter, after writing, set the m17 at 100ms, then read the frequency again. Trigger m18, according to the actual frequency of the first reading, according to the corresponding ratio (d550-d555), and then trigger m10, and then write the frequency, after writing, timing 100ms, read the frequency again, after reading After the frequency trigger m16, write down the value.
Then when the proportion is modified (m101m102m103 is set), the corresponding frequency is calculated according to the read value (the frequency value is put to d2000--d2007), and then the frequency is written. After writing, the timing is 100 milliseconds, and then it starts again. Read the frequency, read it again, trigger m16, write down the value (D590-d597), and then start again and again the frequency of reading.
Ratio values: D550, d552, d554; Frequency values: D2000, d2002, D2004, d2006.
3.6 Problems encountered in the debugging process and solutions
The main problem encountered in the debugging process is during the reading and writing of the communication, because reading the parameters of multiple inverters and writing multiple inverters at the same time are all automatically read and written. In order to minimize the capacity of the read/write program, the program is written. At the time, all variables were used to switch station numbers. Because of problems with Delta's underlying programs, the data that was read was occasionally misplaced. However, because communication was previously required for field communication that was not very demanding, the data was instantaneously misplaced. No effect, and it does not happen often, it usually occurs after a few hours of dislocation and immediately reset immediately, in the scene of less demanding generally do not pay attention.
This time because several frequency converters have been reading, after reading them, if there is a change in the frequencies found, the frequency will be calculated and then automatically written to other frequency converters to keep the synchronization. Therefore, it cannot be read wrongly. The situation, otherwise it will immediately speed, there will be unable to run the situation. Therefore, after the continuous test, when it was found that the communication was being read or written, the program must add the communication to read the data and save the difference data. It is necessary to add the data returned from the communication as a condition (it is necessary to use D1070 and D1071).
4 Conclusion
Synchronous transmission is the basic technology of the mechanized flow production line. Since the era of inverter drive, synchronous transmission has become a typical inverter application technology. The project project meets the automation requirements of the key process of rubber processing through debugging, and shows the engineering capabilities of Delta mechanical and electrical products in advancing the technological progress of the rubber industry.