Mar 29, 2021
Application of frequency converter in polyester staple fiber equipment to expand production plan
With the rapid expansion of my country's polyester fiber industry, related products such as polyester staple fiber have begun to expand in the direction of scale, low cost, localization, and product diversification. In the polyester fiber industry, it began to study short fibers in the 1950s and began to introduce complete sets of production technology and equipment from abroad in the late 1970s. It has achieved impressive results in promoting the rapid development of the industry in a short period of time.
2 70,000 tons of direct-spun polyester staple fiber production process
2.1 Production process
Outlet of melt autopolymerization kettle—booster pump—filter—polymer heat exchanger—melt distributor—static mixer—refrigeration valve—spinning box—spinning metering pump—spinning component—central blower— Spinning oiling—winding and bundling—winding traction machine—feeding wheel—silk barrel—post-spinning bundling device—thread guide—dipping bath—one drafting machine—water bath drafting tank—two drafting machine— Steam heating box—tension heat setting Ⅰ—tension heat setting Ⅱ—tension heat setting Ⅲ—oil spray forest—three-pass drafting machine—wire stacking machine—three rod tractor—tension frame—steam preheating box—crimper— Silk laying machine—oiling device—relaxation dryer—tension machine—cutting machine—baler
2.2 Introduction to process equipment
(1) Melt conveying system mechanism: melt cooler; melt distributor; static mixer; melt filter.
(2) Melt heat preservation system: the melt from the outlet of the polymerization vessel to the melt distributor adopts a liquid phase heat medium circulation system, and the melt distributor and the spinning box share the same vapor phase heat medium system.
(3) Spinning metering pump and components: the metering pump is installed horizontally; the components are bottom-mounted.
(4) Front spinning tow cooling: ring cooling blowing from the center to the outside.
(5) Spinning oiling: unilateral crimping oiler.
(6) Winding traction feeding: 6-rod tractor plus sunflower feeding wheel.
(7) Post-drawing: the first stage is heated by oil bath; the second stage is heated by steam.
(8) Crimping: Tension detection + steam heating + mechanical crimping + hot air chain plate drying.
(9) After spinning combined machine transmission: SAFESAVE frequency converter, single machine frequency conversion speed regulation, on-site centralized control.
(10) Packing device: use packing machine.
3 Composition of polyester staple fiber automatic control system
3.1 Front spinning automatic control system (from the melt booster pump to the reciprocating device of the silk drum)
The system adopts an automatic control unit, which has relatively independent control, high equipment reliability and fast response speed. It is composed of frequency converter, operation interface, communication system, central control system, etc. According to the corresponding bus requirements, there are software and hardware interfaces connected with the workstation communication network, and the above devices can be monitored through the workstation.
3.2 Post-spinning automatic control system (from post-spinning bundling device to packing device)
The packing device adopts the packing machine integrated with SAFESAVE frequency converter. Because the chemical fiber staple fiber is loose and light in specific gravity, it needs to be metered and compressed for many times to be packed into a package. Therefore, the baling metering controller must meet these characteristics and provide corresponding control signals to the PLC and related actuators of the baler , So it adopts advanced imported weighing sensor, measuring instrument, PLC and touch screen.
The post-processing combined machine control system (from the post-spinning bundling device to the slack dryer device), a distributed control system based on fieldbus, through DeviceNet and Logix5555 PLC, realizes all-digital, all-on-site, on-site intelligent control, and then centralizes the equipment Centralized monitoring. The engineer station and the operator stand in the central monitoring room; the post-spinning system 1 is PLC9A, PLC10A; the post-spinning system 2 is public works; the post-spinning system 3 is the relaxation drying system; the post-spinning system 4 is the packing, traction, and cutting. The engineer station installs the RSLogix5000 development version software, and the operator station installs the RSLogix5000 running version software.