1 Introduction
The production of chemical fiber is a continuous process of continuous production. It generally requires more than 8000 hours of continuous operation within one year without failure, that is, the reliability requirement of chemical fiber equipment operation is higher than that of general textile machinery and equipment. Chemical fiber is generally divided into two major categories of man-made fiber and synthetic fiber. China's chemical fiber is mainly composed of synthetic fiber, while synthetic fiber is mainly developed with polyester fiber. Its production scale is getting larger and larger, and the production equipment of polyester staple fiber with an annual output of 30,000 tons to 100,000 tons has become mature. This article takes the production equipment of 30,000 tons of polyester staple fiber per year as an example. Polyester staple fiber production equipment includes textile combiner and aftertreatment combiner.
The textile combined machine includes spinning machine (mainly spinning box, spinning assembly, spinning pump, metering pump, cooling blower and oiling, biphenyl heating, etc.), winding machine (mainly oiling, tractor, Feeding machines, etc.) and wire drum reciprocating devices (mainly including bucket conveying, trolleys, longitudinal and lateral moving devices, tow conveyors, etc.).
The post-processing combine machine includes a bundling frame, a wire guide, an oil immersion tank, a drafting machine, a water bath, a two-way drafting machine, a steam heating pipe, a tension heat setting machine, a cooling spray machine, a three-way tractor, and a wire stacking machine. Machine, three-roller tractor, tension frame, steam preheating tank, crimping machine, wire laying machine, conveyor, slack heat setting machine, traction tension frame, traction machine, cutting machine and packing machine.
2 control system
The block diagram of the control system of polyester staple fiber production equipment is shown in Figure 1. The system uses industrial computer as the upper computer and PLC as the control core of each subsystem. The PLC of each subsystem communicates with each inverter, servo controller, field I/O, etc. via fieldbus (Profibus-DP) to form a fieldbus control system, and the PLC and operator station and engineer station of each subsystem pass Industrial Ethernet (Communication Ethernet) communicates to achieve plant-level and plant-level information management and control, providing real-time data. It provides conditions for the integration of management and control.
2.1 Spinning Union Machine Control
The main technical features of the spinning combine machine:
Daily output: 100t/d;
Number of spinning bits: 32 or 36;
Mechanical speed: 500 ~ 1500m / min;
Wire barrel longitudinal speed: 5 ~ 10m / min;
Wire drum transverse speed: 0.5 ~ 3.5m / min;
The total power of the whole machine is 460kW (including transmission power 160kW, combined heating 300kW).
The control system block diagram is shown in Figure 1. The control system includes the engineering station, the operator station, the spinning control, the winding feed control, and the wire barrel reciprocating control substation.
The operator station completes the display of the production process screen, and can set, modify, record, query, print and record, query and print the process parameters and PID adjustment parameters.
In addition to the main functions of the operator station, the engineering station also has the functions of programming, configuring, debugging and modifying multiple production lines (such as spinning and post-processing combiner), and also has fault diagnosis function.
Both the operator station and the engineering station are implemented by the industrial computer. The human-machine interface adopts a touch screen, which can conveniently set the spinning process parameters, operation control, working condition display, fault alarm display, data record and query on the touch screen.
(1) The block diagram of the spinning machine control system is shown in Figure 2.
Spinning PLC (1PLC) monitors the temperature and pressure of 32 spinning boxes for 32 spinning pumps and 1 oil pump. The system has 4 on-site I/Os, which are realized through human-machine interface. Process parameter setting, modification, related data collection, and control of the operation of the above equipment.
(2) The block diagram of the winding feed control system is shown in Figure 3. The winding PLC (2PLC) controls the speed of the 1~6 traction roller, the godet roller, the feeding wheel, and the oil pump (wheel). Control the spinning blower, with 5 on-site I/Os, through the touch screen to complete the process parameters setting, modification and data acquisition.
Each of the rollers between the traction roller 1 and the traction roller 6 may have a power generation operation state when the tow is pulled, that is, a reverse drag phenomenon, which causes the traction ratio to be unstable. To this end, the common DC bus power supply mode is adopted, and a total of 6 inverters of the traction rollers 1 to 6 are powered by one rectifier unit, so that the feedback energy generated by the motor in the power generation operation can be guaranteed to be consumed in the motor in the electric state. In this way, the negative power energy can be automatically balanced by the DC bus, and the DC voltage of each inverter terminal is connected in parallel, and the capacity of the filter capacitor is increased. Therefore, the voltage of the DC bus does not rise, and the stability of the draft ratio is ensured.
(3) The control system of the reciprocating device of the wire barrel is shown in Figure 4. The wire barrel reciprocating PLC (3PLC) controls the precise transmission of the longitudinal and transverse servo motors of the wire barrel reciprocating device, and realizes the setting, modification and related parameters of the relevant parameters through the touch screen. The collection is also provided with a fixed length device, and the length of each barrel of wire is precisely determined to minimize the waste of the tail wire of each wire barrel.
The direct spinning spinning combine machine should also include the melt piping booster pump PLC station (4PLC), which mainly controls the temperature and melt pressure of the melt piping, and the booster pump adopts AC asynchronous motor drive, and uses vector control. The frequency converter accurately regulates the temperature and regulates the melt pressure in the piping.
Guangzhou LIDONG Garment Industrial Co., Ltd. , https://www.lidongsports.com