IMO Flame Spread Test Apparatus

IMO Flame Spread Test Apparatus is suitable for testing various specimens including flat homogeneous materials, composite panels and tubular components. It is widely applied to evaluate the flame retardant performance of ship bulkheads, deck floor coverings, rail transit interior materials and vertical building finishing materials. The equipment is standardly equipped with a mobile water-cooled heat flux meter, standard calibration aluminum plate, and dual gas supply circuits for propane and methane. It supports two-level calibration modes: daily inspection and monthly full-point calibration. The software plots real-time curves of radiant heat flux and temperature variation, automatically records the flame spread duration at each node, and generates archiveable standard test reports with one click. It meets the routine testing requirements of third-party marine survey laboratories, material manufacturers, and university flame retardant research laboratories.

System Composition:
• Combustion Chamber Unit: gas collection and exhaust hood, infrared radiant heating panel, stainless steel specimen holder, sliding calibration guide rail, ceramic pilot burner;
• Independent Electrical Control Cabinet: main power switch, emergency stop button, radiant panel ignition control, calibration ignition control, variable frequency exhaust control module;
• Gas Supply System: propane test gas circuit, methane calibration gas circuit, air pressure regulating pipeline, precision rotameter, MFC mass flow controller;
• Calibration Accessories: water-cooled heat flux meter, standard porous calibration aluminum plate, handheld anemometer;
• Measurement & Control Unit: Computer + LISUN customized LabVIEW test software.

Product Advantages:
• Split-type safety layout: The combustion chamber is separated from the electrical control cabinet, keeping electrical components away from high-temperature zones to avoid failures caused by long-term thermal aging. The whole unit is constructed of stainless steel for excellent corrosion resistance and easy cleaning.
• High-precision radiant temperature control system: An imported MFC propane mass flow controller regulates the infrared radiant panel with radiant heat flux accuracy up to 0.1 kW/m². The sliding heat flux meter platform enables full-range multi-point calibration, and the software automatically generates standard heat flux calibration curves.
• Standardized safe ignition system: A ceramic pilot burner with dual precision flow meters accurately controls propane and air intake to deliver a stable standard flame of 230±20 mm. It is equipped with multiple safety protections including high-voltage pulse automatic ignition, flame loss gas cut-off alarm, and explosion-proof solenoid valve.
• Complete standardized calibration kit: Factory-supplied accessories include water-cooled heat flux meter, porous calibration aluminum plate and methane calibration assembly. Daily and monthly hierarchical calibration procedures fully comply with national standards and marine regulations, with fully traceable calibration data.
• Intelligent LabVIEW measurement & control system: Guided operation interface divided into three independent modules: calibration, testing and metrology. It automatically captures the timing of flame spread nodes and calculates core indicators such as Critical Flux at Extinction (CFE) and average sustained combustion heat.
• Laboratory-friendly design: Variable-frequency adjustable exhaust fan precisely controls airflow around specimens ≤0.2 m/s. The machine features standard earthing protection, and gas pipelines are fitted with check valves to prevent flashback, effectively avoiding radio interference affecting test data.

Specifications:

Operating Procedures:
Step 1 Pre-test Calibration (Mandatory daily startup procedure)
• Install the calibration plate and water-cooled heat flux meter. Launch the measurement and control software and start the exhaust fan. Adjust the fan frequency, and verify the airflow in the specimen area ≤0.2 m/s using an anemometer.
• Turn on the gas supply and ignite the radiant panel. Maintain thermal equilibrium with a 15-minute soaking period. Perform full-point heat flux calibration from 50 mm to 750 mm sequentially and save the radiant heat flux curve.
• Access the methane calibration interface. Collect reference temperatures corresponding to methane power levels of 1 kW, 3 kW, 5 kW, 7 kW and 9 kW to complete temperature baseline calibration.
• Adjust the pilot flame: regulate gas pressure and flow rate, calibrate flame height and standard specimen clearance, ensuring the flame covers half of the specimen height.

Step 2 Specimen Preparation and Mounting
• Draw a centerline along the length on the specimen surface and mark scales every 50 mm. Differentiate specimens with gaps and specimens without gaps, then secure them with standard aluminum backplates and positioning tabs.
• Mount the assembled specimen into the holder. The entire mounting operation shall be completed within 15 seconds.

Step 3 Formal Combustion Test
• Confirm that the radiant panel maintains thermal equilibrium and the pilot flame adjustment is finished. Click Test in the software to enter the test interface.
• After specimen mounting is completed, click Start to begin timing.
• When the flame front reaches the scale marks of 50, 150, 250…750 mm, click the corresponding scale buttons sequentially. The system automatically records the flame spread duration.
• Once any termination condition is satisfied, including no ignition within 10 minutes, flame stagnation, or flame reaching the end of the specimen, click Stop to terminate the test. Save data and generate the test report.

Step 4 Specification for Replicate Tests
• For non-anisotropic materials, conduct 3 sets of tests in a single direction and take the average value.
• For anisotropic specimens, perform additional replicate tests in the perpendicular direction; calculate results after eliminating extreme values.
• Supplementary replicate tests shall be carried out in accordance with standards under conditions such as specimen non-ignition, incomplete combustion or heavy smoke generation.