Scope of Application

【Operating Instructions】

Fire Resistance Limit Test:According to the requirements of National Standard GB/T 9978-2008, fire resistance tests must utilize open flame heating to subject specimens to flame effects similar to those in an actual fire. This test furnace simulates the actual heating process during a fire to meet the requirements for fire resistance limit testing, thereby comprehensively evaluating the fire endurance performance of the component.

YS-GJL-4 Large-Scale Vertical Fire Resistance Test Furnace for Ventilation Ducts

【Instrument Parameters】

Fire Resistance Limit Test:According to the requirements of National Standard GB/T 9978-2008, fire resistance tests must utilize open flame heating to subject specimens to flame effects similar to those in an actual fire. This test furnace simulates the actual heating process during a fire to meet the requirements for fire resistance limit testing, thereby comprehensively evaluating the fire endurance performance of the component.

Reference Standard:GB 9978-2008 "Fire-resistance tests — Elements of building construction"

Main Technical Performance Indicators:

1. Furnace Temperature ControlAccording to National Standard GB 9978, the temperature rise curve inside the test furnace must satisfy the following equation:

$$T - T_0 = 345 log_{10}(8t + 1)$$

Where:

• $t$ = Time elapsed during the test (min)

• $T$ = Furnace temperature at time $t$ (℃)

• $T_0$ = Initial furnace temperature, which should be in the range of 5℃ to 40℃.

2. Pressure RequirementsFurnace pressure is measured at a height of 3m inside the furnace, 100mm away from the specimen surface:

• a. After 5 minutes from the start of the test: Furnace pressure is 15Pa ± 5Pa.

• b. After 10 minutes from the start of the test: Furnace pressure is 17Pa ± 3Pa.

3. Fire Resistance Limit Criteria

• a. Loss of Integrity.

• b. Loss of Insulation: Occurs when the average temperature rise on the unexposed surface exceeds the initial average surface temperature by 140℃, or when the temperature rise at any single point on the unexposed surface exceeds the initial temperature at that point by 180℃.

Technical Specifications

• Furnace Type: Vertical comprehensive fire resistance test furnace

• Chamber Dimensions: 3.0m × 3.0m × 1.2m

• Fuel: Natural Gas or Liquefied Petroleum Gas (LPG)

• Max Operating Temperature: 1300℃

• Burner Quantity: 8 sets

• Exhaust Gas Temperature: < 100℃

• Exhaust Air Volume: ≈ 16,000 m³/h

• Furnace Wall Temp Rise: < Ambient Temp + 40℃ (excluding areas around burners and observation windows)

• Insulation Material: Mullite refractory bricks; Zirconium-containing cotton modules lining the flue.

• Thermocouples:

• Furnace Thermocouples: ±15℃

• Back Surface Thermocouples: ±4℃

• Moving Thermocouple: ±4℃

• Ambient Thermocouple: ±1℃

• Furnace Thermocouples: 9 units

• Back Surface (Unexposed) Thermocouples: 30 units

• Moving Thermocouple: 1 unit

• Ambient Thermocouple: 1 unit

• Specs: Furnace thermocouples comply with GB9978.1 and GB/T16839.1 (Nickel-Chromium/Nickel-Silicon, Type K).

• Accuracy:

• Interfaces: 30 reserved interfaces for back surface testing, allowing simultaneous measurement of 30 positions.

• Observation Windows: 4 located on the rear wall of the furnace.

• Combustion Control Mode: Proportional combustion, automatic furnace pressure control, automatic temperature regulation, programmed temperature curve control, and computer-aided management.

• Exhaust Mode: Rear mechanical exhaust, connected to a water-wash dust removal tower.