The fire resistance test of nozzle brick is a key index to evaluate its structural stability in high temperature environment. The following are commonly used fire resistance test methods:

I. Standard pyrometric cone method

This is the most commonly used fire resistance test method, according to the national standard GB/T 7322-2017 "Fire resistance test method for refractory materials". The specific steps are as follows:

Sample preparation: the nozzle brick material is made into truncated triangular cone shape, with each side of the upper bottom being 2mm long, each side of the lower bottom being 8mm long and 30mm high, and the cross section being an equilateral triangle.

Testing process: Put the test cone and the standard pyrometric cone with known fire resistance into a high-temperature furnace and heat it according to the specified heating rate. When the test cone bends down due to its own weight and contacts the bottom plate, the corresponding temperature is the refractoriness of the material.

Result judgment: By comparing the bending of the test cone with the standard cone, the fire resistance of the sample is determined.

II. High temperature furnace heating method

Sample preparation: the nozzle brick sample is processed into a standard size sample.

Heating process: put the sample into a high-temperature furnace and heat it at a certain heating rate to observe the deformation or melting of the sample at high temperature.

Record of results: Record the temperature at which the sample begins to deform or melt as a reference value of fire resistance.

III. Thermal expansion rate test

Equipment: Use thermal expansion instrument or microscope and other equipment.

Testing process: heating the sample in a certain temperature range and measuring its length change to determine the deformation of the material at high temperature.

Results Analysis: The fire resistance of the material was indirectly evaluated through the change of thermal expansion rate.

IV. Thermal shock stability test

Test purpose: to evaluate the thermal shock resistance of Shuikou brick during rapid cooling at high temperature.

Test method: heat the sample to a certain temperature, then quickly cool it, and repeat it for many times to observe whether the sample has cracks or spalling.

V. Load softening temperature test

Test purpose: to evaluate the deformation temperature of nozzle brick under high temperature load.

Test method: Apply a certain load (such as 0.2MPa) to the sample in a high-temperature furnace and observe its deformation at high temperature.

matters need attention

Standard basis: The fire resistance test shall be conducted in strict accordance with the national standard GB/T 7322-2017 to ensure the accuracy and reliability of the results.

Test environment: During the test, the heating rate and furnace atmosphere should be controlled to avoid the influence of external factors on the test results.

Professional equipment and personnel: It is recommended to use professional fire resistance testing equipment and operate it by qualified laboratories or professionals.

Through the above method, the fire resistance of nozzle brick can be accurately evaluated, and its stability and reliability in high temperature environment can be ensured.