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JAF Calorimeter

JAF Calorimeter

Isothermal Conduction Calorimeter


The JAF conduction calorimeter is designed to measure the isothermal heats of hydration of small samples of cements. The system can also be used to obtain information on the reaction rate for a wide range of chemical and biochemical processes.

The principle on which the calorimeter works is that heat generated during the chemical reaction flows rapidly through a thermal conductor to a heat sink which is maintained at a constant temperature by a surrounding water bath. The conduction path is formed by a sensitive thermopile which produces an electrical output proportional to the heat flow through it.

When used for cement analysis, the apparatus cuts out the tedium of the standard vacuum flask heat of solution method for measuring the heat of hydration of cements.

Results can be obtained at any selected time interval, and coefficients of variation of 0.9% have been obtained at three days, which is a considerable improvement over the heat of solution method.

An electronic interface connects the two calorimeters to an IBM compatible PC, and all the software required to collect and analyse the data is supplied.

The standard JAF conduction calorimeter system consists of:-

  1. Two medium - sensitivity perspex JAF calorimeters with standard and small sample containers.
  2. A water bath system complete with cooler to maintain the calorimeters under isothermal conditions.
  3. An electronic interface to allow the calorimeter outputs to be collected and then analysed by computer.
  4. Software, spare parts etc.
  5. Computer available as an optional extra if required.
  6. A high temperature system is also available, which operates at temperatures up to 96�C. Two stainless steel calorimeters are supplied for temperatures above 50�C.


  • Main bath 900 x 420 x 490mm
  • Reservoir bath 450 x 350 x 305mm
  • Cooler 360 x 465 x 300mm
  • Interface 325 x 245 x 105mm
  • Weight 106kg ( empty )

Electrical supply

  • 240v 50Hz 1ph
  • 120v 60Hz 1ph

More technical information

Software Information