𝐓𝐨𝐝𝐚𝐲'𝐬 𝐊𝐍𝐎𝐖𝐋𝐄𝐃𝐆𝐄 𝐒𝐡𝐚𝐫𝐞 : 𝐄𝐱𝐭𝐫𝐮𝐬𝐢𝐨𝐧 𝐒𝐞𝐫𝐢𝐞𝐬 𝐏𝐚𝐫𝐭 𝟒: 𝐓𝐡𝐞 𝐌𝐚𝐭𝐞𝐫𝐢𝐚𝐥𝐬 𝐁𝐞𝐡𝐢𝐧𝐝 𝐭𝐡𝐞 𝐌𝐞𝐥𝐭

 𝐓𝐨𝐝𝐚𝐲'𝐬 𝐊𝐍𝐎𝐖𝐋𝐄𝐃𝐆𝐄 𝐒𝐡𝐚𝐫𝐞

⚙️ 𝐄𝐱𝐭𝐫𝐮𝐬𝐢𝐨𝐧 𝐒𝐞𝐫𝐢𝐞𝐬 𝐏𝐚𝐫𝐭 𝟒: 𝐓𝐡𝐞 𝐌𝐚𝐭𝐞𝐫𝐢𝐚𝐥𝐬 𝐁𝐞𝐡𝐢𝐧𝐝 𝐭𝐡𝐞 𝐌𝐞𝐥𝐭

Every extruder speaks the same language;

torque, pressure, and temperature

but each polymer cooks at its own pace.

Rush XLPE and it burns.

Hold EVA too long and it curdles.

Get the heat, timing, or mixing wrong, and you’re not running cable,

you’re scraping the screw like someone cleaning the oven after a failed bake.

Here’s how the main cable compounds behave when you put them under heat and pressure:

▪️ Crosslinking Polyethylenes (XLPE, Semicon)

Peroxide or silane-based PE systems that demand discipline.

LV XLPE runs hot (165–185 °C) because it crosslinks after extrusion.

MV/HV XLPE runs cool (110–130 °C) so it doesn’t harden before hitting the nitrogen tube at 400°C.

High-compression screw (2.5–3.5:1) keeps melt uniform.

Lose control of heat or residence time and you get gels (pre crosslink) a chemistry that finished before you wanted it to.

▪️ Thermoplastics (PVC, PE, PP)

The forgiving crowd.

Polymers with relatively wider thermal window and less chemically reactive.

But PVC shears easily and burns if you get cocky.

PE is more forgiving; PP punishes bad cooling.

Moderate compression (~2.5:1), 150–210 °C zone temps.

▪️ Filled & Flame-Retarded Systems (EVA, XLEVA, LSHF)

Heavy, loaded, and moisture-sensitive.

Low compression (1.4–2:1), 120–165 °C melt.

Drying <0.05% moisture or you’ll see steam voids.

Apollo depth too shallow?

You’ll scorch it before it even touches the die.

XLEVA sits here because it behaves like EVA but crosslinks after.

▪️ Engineering Thermoplastics (Nylon, PVDF, TPE)

The special-sheath materials.

High temp (190–250 °C) and zero tolerance for moisture.

Nylon foams instantly if not dried.

PVDF hates over-shear.

TPE collapses if you drift a few degrees too hot.

tooling must be mirror-clean.

At the end of the day, you’re not just running an extruder,

you’re the chef keeping every polymer on recipe.

Control the heat, control the timing, and the cable comes out perfect every time.

source : Hazim Shafik