It is of vital importance for the safety of refinery and petrochemical process vessels & transfer lines e.g. to avoid overheating. This overheating mostly occurs due to damages on the inside of the equipment (by failure of the refractory lining e.g.) which can not be controlled.

Temperature observation by the means of sensors will not be an effective method, due to the large area to be controlled.

Depending on the application and the temperature limites admissible for the vessel, we recommend a relatively simple but effective solution:

Temperature indicating paints
The vessel/tranfer line e.g. is coated with the temperature indicating paint. Upon reaching a temperature of XX °C (caused by failure of the refractory lining e.g.) the colour will change in the effected area.

Colour change is a slow and irreversible process, the intensity and speed depends on the duration and degree of the temperature load. Once the colour has changed, this will remain permanent, even after cooling down.

  • This is an early warning indicator of overheating.
  • The change in colour is clearly visible.
  • Damaged area is easily locatable.
  • The optical difference can be detected at any time.
  • The colour has a high stability over several years.

Productrange temperature indicating paints thenex GmbH
The products are temperature sensitive and changes from colour when a certain temperature is obtained. Most paints are available in two types, the irreversible and the reversible temperature sensitive colour paints. The irreversible paints are signal paints with a temperature range from 145 ºC to 600 ºC. Depending on the temperature there are three qualities available. Some products have more then one colour change at different temperatures but irreversible paints will not change back to the original colour. For outdoor application a zinc rich primer, is used on blasted steel up to 600 ºC. The primer guarantees a good adhesion and corrosion resistance of the paint system and after that the paint is applied. Next to the irreversible temperature sensitive colour paints there are also reversible temperature sensitive paints. The temperature range varies. and are available in many colours. The colour of the paint becomes transparent and at a specific temperature the colour of the primer underneath becomes visual. When temperature drops down the original colour returns back. This type of paint is only available in a two component PU-coating and the reversible temperature sensitive paints are not suitable for outdoor use, even exposed behind glass permanently the colour will fade away. We can also offer temperature resistant paints for different temperature levels and environments. Please send us your inquiry.