Fire Resistance Test Furnace for Vertical applications: This vertical model is designed to simulate the extreme heat conditions of real fires that may reach up to 1,200°C (2,192°F) in maximum temperature. Such temperatures are required to assess the fire resistance rating of building materials and components according to stringent safety criteria as ASTM E119, or ISO 834.
The furnace is working on a pre-determined time-temperature curve, meanwhile during the test temperatures are increasing rapidly. In five minutes, it will have hit 538°C (1000°F), and at thirty minutes, a homogenous bake through at all sides of the oven will exchange temperatures with about 1,000°C (1832°F) Intended exposure durations, typically up to four hours for testing protocols, require the furnace to maintain stable thermal conditions.
Gas burners are located at the bottom of these furnaces and their flames provide high-intensity, and consistency heat source. Higher-end models have modulating gas controls, so they will work very hard to keep the flame constant at its precise setting, going no more than 2% above or below where it is supposed to be. And this precision is important if you want to get results that are reproducible but also accurate.
Inside the furnace, high-density refractory bricks will be used to ensure that they can withstand extreme temperatures for extended periods of time. Thermal conductivity as low as 1.5 W/m·K, which delays the heat leakage and use high efficient of energy. Similarly, refractory linings minimize thermal losses (which are very high in fired heaters) allowing the furnace to reach and maintain maximum temperatures without consuming excessive energy.
In testing scenarios, these materials are often tried to their thermal limits. To illustrate one specific example, fire-rated doors are tested to confirm that they do not lose their integrity at peak temperatures over certain lengths of time. To be compliant, a steel fire door must not bend or allow penetration of flames when tested for 90 minutes at 1,093°C (2,000°F). UL’s data from 2022 testing also found that 85% of materials tested passed within these constraints.
Another important consideration is airflow regulation, keeping the oxygen levels regulated to maintain full combustion so that furnaces run at the maximum temperature efficiently. Accurate dampers and regulators are important for controlling air flow (and thus heat distribution) through the test specimen.
Like Thomas Edison said, “What you are will show in what you do.” The ability of a Horizontal Fire Resistance Test Furnace to achieve these high temperatures is testimony to the calibration of its engineering, and in turn can provide a more reliable safety assessment. Read more: Vertical Fire Resistance Test Furnace