What are the characteristics of chemical fiber spinning machine?

Chemical fiber spinning machine is the key equipment to make high polymer into chemical fiber, which mainly includes melt spinning machine and solution spinning machine, and has the following characteristics:

High-precision measurement and transportation

Accurate material measurement: the chemical fiber spinning process requires extremely high material measurement accuracy. The spinning machine is equipped with high-precision metering pump, which can accurately control the output of polymer melt or solution and ensure the uniform quality and performance of each fiber. For example, in the production of high-performance fiber, the precision of metering pump can reach within 0.5% to ensure that the linear density deviation of fiber is extremely small.

Stable material conveying: In order to ensure the continuity and stability of spinning, the spinning machine adopts advanced conveying system. The screw extruder in the melt spinning machine can uniformly heat and melt polymer particles and stably transport them to the spinning assembly; The solution conveying pipeline in the solution spinning machine has good corrosion resistance and heat preservation performance, which prevents the solution from precipitation or temperature change during the conveying process and affects the spinning quality.

Efficient heating and cooling system

Uniform heating: In melt spinning, the polymer needs to be heated to a molten state. The heating system of spinning machine usually adopts electric heating or heat conduction oil heating, which can heat the polymer evenly to the set temperature in a short time. For example, the heating elements in the spinning box are evenly distributed, which can control the temperature deviation of each point in the box within 2℃ and ensure the stability of polymer melt fluidity and spinning performance.

Rapid cooling: During the spinning process, the filaments extruded from the spinneret hole need to be cooled and solidified rapidly to form a stable fiber structure. Melt spinning machine usually adopts side blowing or ring blowing cooling mode, while solution spinning machine adopts coagulation bath cooling. The cooling system can accurately control the temperature, speed and flow rate of the cooling medium, so that the filaments can meet the curing requirements in a short time, and the production efficiency and fiber quality can be improved. For example, the side-blowing cooling device can cool the filament to room temperature in a few seconds to form fibers with certain strength and orientation.

Precision spinning assembly

Precision machining of spinneret: spinneret is one of the core components of spinning machine, and its machining accuracy directly affects the quality and performance of fiber. The precision of the diameter and shape of the spinneret orifice is extremely high, and precision machining technology, such as laser drilling and EDM, is usually used to control the diameter deviation of the spinneret orifice within 5 μ m and the length-diameter ratio of the orifice is uniform, so as to ensure the uniformity and stability of filament extrusion.

Optimal design of spinning assembly: The spinning assembly includes spinneret, distributor and filter screen, and its structure and design are very important to the spinning process. Reasonable design of spinning assembly can make polymer melt or solution be fully and evenly distributed and filtered before entering the spinneret hole, remove impurities and gel particles, and improve fiber quality. For example, the adoption of multi-layer filter screen structure can effectively filter out tiny impurity particles and ensure the cleanliness of fibers.

Automatic control and monitoring

Advanced control system: modern chemical fiber spinning machine adopts automatic control system, which can realize accurate control and real-time monitoring of various parameters in spinning process. Through PLC or DCS control system, the parameters such as metering pump speed, heating temperature, cooling wind speed and winding speed can be programmed and automatically adjusted to ensure the stable operation of spinning process. At the same time, the control system also has the function of fault diagnosis and alarm, which can find and handle the abnormal situation in the production process in time, and improve the production efficiency and the stability of product quality.

On-line monitoring technology: In order to further improve the fiber quality, the spinning machine is equipped with on-line monitoring equipment, such as fiber diameter measuring instrument, tensile strength measuring instrument and moisture content measuring instrument. These monitoring devices can detect the fiber quality parameters in real time and feed back the data to the control system, so as to adjust the spinning process parameters in time and ensure the fiber quality meets the standard requirements. For example, the on-line fiber diameter measuring instrument can monitor the change of fiber diameter in real time. When the diameter deviation exceeds the set value, the system automatically adjusts the spinning speed or drafting multiple to restore the fiber diameter to the normal range.

Diversified product adaptability

Production of various fiber varieties: Chemical fiber spinning machine can produce many different types of chemical fibers, such as polyester fiber, polyamide fiber, polyacrylonitrile fiber, polyvinyl alcohol fiber and so on, by adjusting process parameters and spinning components. According to different fiber varieties, we only need to change the corresponding spinneret and adjust the spinning temperature, speed and drawing multiple, so as to realize the production of different fibers and meet the market demand for diversified fiber products.

Fiber production with different specifications and properties: Spinning machines can also produce fibers with different specifications and properties, such as fibers with different linear density, strength, elongation and gloss. By changing the size and number of spinnerets, adjusting the spinning process conditions and the subsequent post-treatment process, various performance indexes of fibers can be accurately controlled, and chemical fiber products meeting the needs of different application fields can be produced. For example, by adjusting the draft ratio and heat setting process, high-strength industrial fibers and soft and comfortable civil textile fibers can be produced.