▪ I-Raw material analyses: Based on the technical data sheet of the raw material, we perform analyses of the raw materials according to the following standards: (ISO1183, ISO1133, EN 728). This includes density, flow rate index, and oxidation induction time.

▪ II-Geometric: Before starting the analyses, we measure the diameter, thickness, and ovality using a circometer, palmer, and caliper.

▪ III-Physical analysis:

    • A- Oxidation induction time: Differential scanning calorimetry is a technique used to study what happens to polymers when they are heated. This technique is used to study a polymer’s thermal transitions. Thermal transitions are the changes that occur in a polymer when you heat it, like the melting of a crystalline polymer or the glass transition.

    • B- Flow rate index (MFI): This test determines the flow rate index, the extrusion speed of a melted resin through a die of specific length and diameter under prescribed temperature conditions, load, and piston position in an extrusion plastometer, expressed in terms of extruded mass per specified time interval.

    • C- Density

    • D- Longitudinal and circumferential shrinkage when hot: A tube of a given length is immersed in an inert oven maintained at a specified temperature for a specified duration.

▪ IV-Mechanical analysis

• A-Milling machine: Prepare the test specimens for the tensile test according to the standard ISO 6259-1 and ISO 6259-3.

• B- Tensile strength: Objective: to verify the mechanical characteristics of extruded tubes. The test consists of applying a constant speed traction (25- 100mm/min) to a tube sample until the sample breaks. The force required for deformation and the deformation at break are measured. The deformation at break must be greater than 350%, and the stress at the yield point must be greater than 15MPa for PE80 and 19MPa for PE100.

• C- Hydrostatic pressure resistance: Objective: to verify the tube’s pressure resistance. The test involves applying constant pressure to a tube sample at 80°C for 165 hours and 20°C for 100 hours. At the end of the test, the tube must not have any cracks.

▪ Dichloromethane resistance: The objective is to determine the degree of gelation.

▪ Shock resistance: This mechanical test determines the rigidity of a PVC tube.

▪ Vicat test: The objective is to determine the softening temperature.