Hydraulic presses

The heating of hydraulic presses is another characteristic application of thermal fluids.

In many industrial processes, pressing needs to be done at high temperatures to form materials such as composites, rubber, wood and plastics.

The presses reach the appropriate temperatures using heating systems with thermal oil. The heat produced by thermal fluid boilers is transferred to the plate by a coil arranged inside the plate itself. This thermal fluid heating system confers high temperature uniformity over its entire surface. Also, temperature regulation is very accurate due to separate secondary recirculation groups in each plate, as well as a 3-way valve.

Traditionally, press plates were heated by electrical heating coils, but this system has several drawbacks compared to heating with thermal oil.

• The areas near the electric coils are typically at a higher temperature than areas farther away from the area of the heating. In short, there is little temperature homogeneity in the plate.
• Electrical heating coils can lead to earthing with the consequent danger to the user.
• They often melt, leading to cold areas in the plate and deficiencies in the product finish.
• The energy consumption is high.

Using a thermal oil system, the fluid circulates at high speed through the inside of the plate, transferring the heat efficiently with a low thermal differential between the fluid inlet and outlet.

Boilers can be either electric or liquid or gas fuel and can be placed either on the top of the press or to the side.
Similarly, this system can be customised for each of the presses or centralised with a boiler room and a general circuit supplying each of the presses by different connections.

Nowadays, a Pirobloc thermal oil heating system is the most efficient and sustainable solution for supplying heat for hydraulic presses.