Heater–cooler (hot/cold) mixers

The heater–cooler mixer sits at the heart of PVC dry-blend production. Depending on who you ask it is a hot/cold mixer, a turbo mixer, a high-speed mixer or a high-intensity mixer; all of these names describe the same pairing of a heater mixer followed by a cooler mixer. Erk PVC Makine builds this PVC dry blend mixer in two series under the EPM turbo mixer name.

What the heater mixer does

In the heater (hot) mixer, blades turning at high speed lift the charge into a fluidised vortex. No external heating is applied: temperature rises through friction between particles and between particles and blades. As it climbs, stabilisers and lubricants melt and spread over the PVC particles, and in plasticised recipes the liquids are absorbed into the resin. For rigid PVC, discharge typically happens at around 110–120 °C, with the exact point set by the recipe.

Why the cooler mixer matters

Blend at that temperature, sent straight to a silo or bag, cakes under its own heat, picks up moisture and feeds the extruder unevenly. The cooler (cold) mixer, with cooling water in the vessel wall and a slow-running agitator, typically brings the batch down to around 40–50 °C and hands it on as a free-flowing powder. The two vessels work in parallel: the heater prepares the next batch while the cooler handles the previous one, so sizing them to match each other has a direct effect on hourly output. Our article on how a heater–cooler mixer works goes into more detail.

Which series fits your line?

• EPM-H with horizontal cooler: 150–500 kg per batch, 450–1250 L heater and 1000–3500 L horizontal cooler, for high-tonnage lines and large batches.
• EPM-V with vertical cooler: 100–200 kg per batch, 300–540 L heater and 520–850 L vertical cooler, a compact option for mid-range output and limited floor space.

Both series run 4–6 batches per hour. Figures are for a standard PVC profile formula, may vary with other recipes, and capacities can be adapted to order. For the trade-offs between the two layouts, see horizontal vs vertical cooler mixer.

What drives the decision

Start with the hourly dry-blend requirement of the line, then choose batch weight and batch count to match it; the mixer capacity calculator gives a first estimate. The variety of recipes influences the drive: plants that change recipes often lean towards a frequency variator (FV), while a soft starter (SS) suits fixed recipes. Floor area, ceiling height and cooling water availability settle the choice between a horizontal and a vertical cooler. Planning the mixer together with dosing and feeding systems makes it easier for the whole line to run efficiently.

Further reading for the decision: what determines PVC mixer price for the budget, the industrial mixer types and selection guide for how a turbo mixer compares with ribbon and planetary designs, and PVC turbo mixer maintenance and common faults for life after commissioning.