How to coordinate the control of cable trough extrusion parameters to ensure efficient production?

In the cable trunking extrusion production line, the screw speed, plastic melt pressure and extrusion speed constitute a precise dynamic balance system, and the coordinated control of the three directly determines the product quality and production efficiency. The extrusion process is like a precise symphony, and each parameter is an indispensable performer. Only precise coordination can achieve stable and efficient production.

As the power core of the extrusion system, the screw speed directly affects the conveying volume and plasticizing effect of the plastic melt. When the screw runs at high speed, the number of plastic particles conveyed per unit time increases significantly, and the residence time of the material in the barrel is correspondingly shortened. This means that during the plasticization process, the plastic particles may not be able to fully absorb heat and complete the transition from solid to viscous flow, resulting in uneven plasticization. After the insufficiently plasticized plastic enters the mold, it will not only cause defects such as pockmarks and bubbles in the appearance of the cable trough, but also affect its mechanical properties and reduce the strength and toughness of the product. At the same time, the high-speed screw will also cause the friction of the plastic melt in the barrel to increase, resulting in excessive melt pressure. Excessive pressure will not only cause additional wear on the screw, barrel and other parts of the extruder, increase the equipment maintenance cost, but in more serious cases, it may cause equipment overload or even screw breakage and other faults, interrupting the production process.

On the contrary, if the screw speed is too slow, although the plastic particles have sufficient time to complete plasticization, the delivery volume of the plastic melt is significantly reduced, which directly leads to a decrease in production efficiency. In the context of the continued growth in demand for cable troughs in industries such as electricity and communications, inefficient production is difficult to meet market demand, increasing the production cost and time cost of enterprises. In addition, long-term low-speed operation may also cause the plastic melt to stay in the barrel for too long, causing local overheating and decomposition, which also affects product quality.

As a key indicator in the extrusion process, the plastic melt pressure is closely related to the screw speed and directly affects the mold filling process. Stable and appropriate melt pressure is a key factor in ensuring the quality of cable trough molding. When the melt pressure is insufficient, the plastic cannot fully fill the mold cavity, resulting in problems such as lack of material and insufficient size of the cable trough, making it unable to meet the requirements of engineering installation. If the pressure is too high, the mold may be subjected to excessive load, which may cause deformation and damage to the mold in long-term use, shortening the service life of the mold. Excessive pressure may also cause the plastic melt to overflow from the gap of the mold, forming flash, increasing the workload and cost of subsequent processing steps.

As the output indicator of the entire extrusion production line, the extrusion speed needs to be accurately matched with the screw speed, melt pressure, and subsequent cooling and traction processes. Too fast an extrusion speed will shorten the filling time of the plastic melt in the mold, resulting in insufficient filling; and in the cooling link, due to insufficient cooling time, the cable trough cannot be shaped in time, and deformation, warping and other problems are very likely to occur. Too slow an extrusion speed not only reduces production efficiency, but may also cause the plastic melt to stay in the mold for too long, causing material accumulation and local temperature rise, affecting product quality. For example, when the extrusion speed does not match the screw speed, if the screw speed is high and the extrusion speed is low, the melt pressure in the barrel will continue to rise, increasing equipment risks; conversely, if the screw speed is low and the extrusion speed is high, insufficient feeding will occur, and a continuous and stable extrusion process cannot be formed.

To achieve the coordinated control of screw speed, plastic melt pressure and extrusion speed, it is necessary to comprehensively consider factors such as raw material characteristics, mold structure and equipment performance. Operators need to set the appropriate screw speed range according to the melting characteristics of different plastic raw materials, such as polyvinyl chloride (PVC) and polyethylene (PE), and monitor the melt pressure in real time through pressure sensors to dynamically adjust the screw speed and extrusion speed. At the same time, advanced extrusion production lines are usually equipped with automatic control systems, which can automatically adjust the operating status of each link according to the preset process parameters to ensure the stability and reliability of the entire extrusion process.

The coordinated control of screw speed, plastic melt pressure and extrusion speed in the cable trough extrusion production line is the core technology to ensure product quality and production efficiency. Only by deeply understanding the relationship between the three and adopting scientific and reasonable control strategies can we achieve high-quality and efficient production of cable troughs and provide reliable product support for infrastructure construction such as electricity and communications.