To produce PVC pipes, it’s necessary to use a variety of raw materials such as: S-PVC resin, metal stabilizers, fillers, pigments and lubricants. To establish a good formulation and have the correct dosage of the external lubricant Ceralene 1M or Ceralene 2E,  there are several parameters that must be controlled: torque, compression ratio, screw speed, motor load, production output, the temperature of each zone of the extruder and the dimensions of the PVC pipe to be obtained (diameter, thickness and weight).

How does an external lubricant such as Ceralene 1M or Ceralane 2E work?

In the extrusion process, all the ingredientes enter the hopper at an initial temperature of 50°C, where those with In the extrusion process, all the ingredientes enter the hopper at an initial temperature of 50°C, where those with the lowest drop point melt first. The constant rotation of the screws within the metallic walls of the extruder generate compression and shear forces in the granules and, due to friction and external heating by electrical resistance, the softening of the plastic material and its partial melting takes place (75% is considered to be in a melted state and the rest in a solid state). As the material progresses towards the end of the screw it turns into a melted phase. The temperature reaches 100°C, where the one pack stabilizers melt followed by the external lubricant Ceralene 1M or 2E. The external lubricants, upon reaching their melting point, create an external film that protects the melted PVC compound from the metallic parts of the screw and the walls of the extruder, generating a reduction in the friction between the PVC mass and the metallic parts, avoiding a temperature rise and the degradation of the PVC polymer.

The benefits in production of the use of the external lubricant Cerlane 1M or 2E are a decrease in the melt pressure, greater energy efficiency by reducing the motor load, better management of the rheology of the melted mass and reduction of material losses. Among the advantages over the final product that the use of the external lubricants give us are: smooth surfaces, glossy finishes, and well homogenized colors without horizontal or circular marks on the pipes.

Sources:
-“The plastic: a history of more than 100 years of innovation”. PlasticsEurope https://www.plasticseurope.org/es/about-plastics/what-are-plastics/history. Accessed 06/08/2021
-Arístides Sotomayor / George Power. Clean technologies and the environment in the Peruvian sector. Practical cases. 1st ed. 2019, pp. 404-411. Accessed 06/09/2021.
-Rainer Wuest, Rigid PVC Technical Training, Euroceras, June 10th, 2021, Germany, Virtual Conference, Manufacturer's Technical Training.