AS 1774.11:2015 pdf free.Refractories and refractory materials – Physical test methods, Method 11: Determination of thermal expansion.
This International Standard specifies test methods for the thermal expansion of refractory products. It describes a method for determining the linear thermal expansion percentage, the linear thermal expansion curve, and the linear thermal expansion coefficient.
This International Standard includes the following three test methods for the thermal expansion of refractory products:
a) a contact method with a cylindrical test piece;
b) a contact method with a rod test piece;
c) a non-contact method.
The characteristics of these methods are shown in Annex A.
4 Contact method with cylindrical test piece
4.1 Principle
The amount of dimensional change of the cylinder test piece is continuously measured by using a contact type measurement instrument while heating at the specified rate in a heating furnace, and the linear thermal expansion rate, curve of linear thermal expansion rate, average coefficient of linear thermal expansion, and coefficient of linear thermal expansion are obtained.
4.2 Apparatus
4.2.1 Thermal expansion test apparatus
4.2.1.1 General
The circular pressure rod (1), test piece (5), and supporting rod (9) of the thermal expansion test apparatus shall be set in a heating furnace and all central axes aligned vertically. This alignment shall be maintained throughout the test as shown in Figure 1 and Figure 2. The structure of the apparatus shall be such that the thermal expansion of the test piece produced when a pressure of 0,01 MPa is applied to the direction of this central axis and the temperature is raised can be calculated from the relative change amount of the length of detecting tubes (7) and (8) contacted with the spacers (2) and (6) of the upper surface and the lower surface of the test piece. The contact force shall not change more than ±1 N.
4.2.1.2 Constitution of thermal expansion test apparatus
The apparatus shall be comprised of the following.
a) Fixed pressure rod (1): The fixed pressure rod (1) shall be a cylindrical refractory material of at least 45 mm outside diameter. In the apparatus in Figure 3, the hole of concentric circle for passing through the tubes for detecting the upper and lower positions shall be provided.
Care shall be taken so as not to contact with the hole of the upper lid of the heating furnace.