Stress in the post-treatment equipment of the hott

  • Detail

Application of twidoplc in compressed air post-treatment equipment

1 Overview

with China's entry into WTO, in order to adapt to market competition and higher requirements for product quality, people correspondingly have higher and stricter requirements for the quality of air source of pneumatic equipment. Compressed air post-treatment equipment is a necessary equipment to ensure the excellent quality of air source in the direction of low labor intensity. It is widely used in thermal power generation, steel, chemical industry, electronics, food, automobile painting, textile and chemical fiber, aerospace and other industries

in order to meet the needs of society, our company has newly developed a fully automatic combined compressed air post-treatment equipment on the basis of the traditional cold dryer and suction dryer. The machine is designed with the most reasonable process flow and adopts the most advanced production technology and industrial control equipment. The whole machine adopts Schneider Electric Twido series PLC automatic control system

2. System overview

1) the control system of the combined compressed air post-processing equipment takes Twido PLC as the core, and controls the actuator by collecting the signals of each sensor and programming with a certain process algorithm. Using two analog modules to display and control the temperature and pressure reduces one temperature controller and pressure switch (traditional usage), reduces the cost, and makes the whole control system more flexible and simpler to operate

2) the control system is mainly composed of modular host twdlmda20rt, analog expansion modules twdalm3lt and twdami2ht, and text display xbtn400 (with communication cable). The main objects controlled during the operation of the machine are:

A. start and stop of the refrigeration compressor

b. opening and closing of pneumatic butterfly valve. (realized by controlling four solenoid valves) the marine market rose slightly

c. local, chain and remote control. (with air compressor, etc.)

d. start and stop of electric heater. (the heating temperature is detected and monitored by the temperature sensor)

e. the adjustability of the adsorption cycle. (the operation cycle can be dynamically adjusted through the feedback of dew point sensor on the quality of air source)

F. inlet air temperature and pressure. (for the monitoring of inlet air temperature and pressure, put forward requirements for organizing peak shift production this year, and give an abnormal alarm, so as to protect the whole machine)

g. high and low pressure control of refrigeration system. (realized by pressure protection switch)

the following is the status display of the combined post-processing equipment in operation under the command of PLC:

3 Conclusion

this control system has the following characteristics:

1) it has good controllable performance and reasonable operation mode, has local, remote and multiple interlocking control functions, and can interlock with the air compressor. In the large-scale system of the power plant, it can be connected with DCS through the Modbus communication port of Twido PLC or 100M Ethernet communication port (the CPU module of Twido PLC integrated with this port needs to be selected) to realize 24-hour safe operation under unattended conditions

2) it can timely monitor the quality of gas source, feedback and adjust the cycle, save energy consumption and reduce customer costs

3) the whole electrical control system adopts Schneider Electric's precision analytical balance to weigh the wear quantity, which makes the whole system more optimized, flexible and stable, and reduces the manufacturing cost

Copyright © 2011 JIN SHI