FERRO Process Temperature Control Rings

FERRO Process Temperature Control Rings

The multifunctional PTCR concept comprises • improved ceramic PTCR rings • improved, convenient packaging • the PTCR micrometer with numerical or digital read-out • a batch-specifific temperature table


The multifunctional PTCR concept comprises • improved ceramic PTCR rings • improved, convenient packaging • the PTCR micrometer with numerical or digital read-out • a batch-specifific temperature table

Process Temperature Control Rings 

Higher quality products and lower costs through improved, reliable fifiring control

Take control of your fifiring process

In the manufacture of ceramic products, few things are as critical as accurate control of the fifiring process. 

After all, the results have a direct effect on the quality - and the costs - of the fifinal product. 

Optimal fifiring control requires both accurate measurement of the heat treatment - the temperature and its effect over time - together

with the ability to control the temperature and the uniformity of its distribution throughout the kiln. 

Effective temperature measurement is the key to guaranteed product quality

Most conventional temperature measurement techniques are limited both in time and in location. 

For example, the thermocouples generally used in the ceramic industry do not measure the temperature of the product itself, 

but that of its vicinity. They are also limited to measuring radiated heat, and take no account of heat transferred from kiln furniture.

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FERRO Process Temperature Control Rings 560~1750℃ Ptcr

A PTCR is a ceramic device that registers the total amount of heat transferred to it.
Because of the advanced technique and materials applied and used for this product,it gives a fair representation of the real heating process taking place in a kiln at the location of the ring. PTCR helps to achieve a reliable, outstanding and regular quality level.

The actual set temperature of a kiln during a firing process, as measured by thermocouples,does not give any guarantee of the repeatability of process conditions which of course will harm the quality of the products. A thermocouple merely gives a specific spot temperature,which is not the same temperature as the one at the position of the product. The ultimate temperature of the product is determined by the total transferred heat. This is not measured by the thermocouple. Besides, the same set temperature in different kilns or kiln layouts does  not guarantee the same heat treatment.

Method of use


PTCR rings can be placed at almost any location in the kiln, on kiln furniture, trolleys or transports. 

The use of both multi-location and multi-level positioning is recommended, as this provides the most insight into the heat treatment distribution within the kiln.


The contraction of the PTCR diameter reflflects the actual heat treatment at the point where the ring was located in the kiln. 

The diameter is easily measured using a PTCR micrometer - only a single measurement is required (as shown).

Converting to ring temperature

The measured ring diameter is converted to ring temperature using the conversion table enclosed in each packing unit.

 Each table is specifific to the particular batch of rings, for accuracy and convenience