BS ISO 18099:2013 pdf free

BS ISO 18099:2013 pdf free.Thermal insulating products for building equipment and industrial installations
Test specimens shall be sawn or cut with a thin-walled steel tube from the product in the direction in which the measurement of the coefficient of linear thermal expansion shall be made and in which the linear dimensions are to be recorded.
Special requirements for preparation such as annealing or drying under specified conditions shall be indicated where relevant in the product standard.
For anisotropic products, the measurements shall be carried out both in the direction of the length and of the width.
Clean the test specimen and install it in the dilatometer, making sure that the end surfaces as well as the contact surfaces of the dilatometer are free of foreign particles.
Measure its length at (23±2) °C which shall be considered as the reference temperature.
Place the thermocouples in representative manner, ensuring good contact with the test specimen.Insert the dilatometer assembly in the furnace or in the test chamber.
Heat or cool the system, making sure that the temperature gradient given in the relevant product standard is respected. If no information is available, do not exceed 3 K/min and 1 K/min for the last 50 °C interval.
Stabilize the temperature at temperature intervals not greater than 50。C over a time sufficient to obtain homogeneous temperature within the test specimen. Usually, 30 min is sufficient.
Measure the temperature and the test specimen length when constant temperature is recorded (±2 K for high temperature and±1 K for low temperature). Record the length variation/temperature curves continuously, following the instructions specific to the instrument used.
Bring the temperature back to the reference value and remeasure the length. If irreversible changes have occurred, repeat the cycles until only reversible changes occur.
NOTE It has not been possible to include a statement on the accuracy of the method in this edition of this International Standard, but it is intended to include such a statement when this International Standard is next revised.BS ISO 18099 pdf download.