ISO 817 & IEC 60335-2-40 Burning Velocity Test Apparatus

Precise Measurement of Laminar Burning Velocity for Flammable Gases and Refrigerants

The KINGPO Burning Velocity Test Apparatus is a high-performance, dual-standard compliant instrument engineered for the accurate determination of laminar burning velocity (Su) in premixed combustible gas-air mixtures. It fully satisfies both:

• ISO 817:2014 Annex C (Refrigerants — Designation and safety classification)
• IEC 60335-2-40:2022 Clause 22.116.6 (Household and similar electrical appliances – Safety – Particular requirements for electrical heat pumps, air-conditioners and dehumidifiers – Burning velocity measurement apparatus)

This vertical tube flame propagation system is widely recognized as the reference method for evaluating the combustion properties of mildly flammable refrigerants (A2L class), highly flammable A3 refrigerants, synthetic mixtures from lithium-ion battery thermal runaway vents, and other low-GWP alternative refrigerants. The apparatus enables manufacturers and testing laboratories to generate burning velocity data required for both refrigerant safety classification and household appliance safety certification under the latest IEC household appliance standard.

The system uses a high-speed camera to record flame front propagation inside a controlled vertical glass tube and calculates the unstretched laminar burning velocity according to the mass conservation principle: Su = (volume consumption rate of unburned mixture) / flame surface area during the steady, uniform propagation phase.

This method delivers outstanding repeatability, excellent visual documentation, and direct traceability to the most current international safety requirements for refrigerants and electrical appliances containing flammable refrigerants.

Burning Velocity Test Apparatus Product Features

High-Precision Flame Imaging and Analysis

• Industrial-grade high-speed camera: ≥1,000 fps at full frame, up to ≥70,000 fps at reduced resolution (1280×8 pixels)
• Ultra-short exposure time down to 1.0 μs with 60 dB dynamic range — ideal for capturing weak, slow-propagating A2L flames or fast A3 flames
• Proprietary software automatically tracks flame contour, calculates projected area (af), actual curved flame surface area (Af), and computes unstretched burning velocity with high precision (measurement range 0–150 cm/s, accuracy 0.01 cm/s)

Robust and Safe Mechanical Construction

• 10 L quartz glass mixing vessel, pressure resistance ≥1 MPa, equipped with magnetic stirrer for uniform gas premixing
• Vertical combustion tube: 1200 mm length, 40 mm inner diameter, 2 mm wall thickness; optical transmittance >99.9% (250–600 nm), pressure resistance >2 MPa, ultimate vacuum <20 Pa, leakage rate <5 Pa/min
• Hardened smoothing sieves and high-temperature damping screens to resist chemical attack (HF, NH3, etc.) and prevent contamination
• Induction spark ignition: 1 mm tungsten electrodes, 6.4 mm gap, powered by 15 kV / 30 mA transformer; adjustable spark energy (~10 W for 0.3 ± 0.05 s duration)

Fully Automated Control & Data Handling

• Siemens PLC control system integrated with NI LabVIEW supervisory software
• Complete automation of: vacuuming, nitrogen purging, precise gas mixing/filling, ignition synchronization, high-speed camera triggering, real-time temperature & pressure monitoring, flame visualization, burning velocity calculation, and data archiving
• Pressure transducer: -0.1 to 0.5 MPa range, 4–20 mA output, long-term stability ≤0.2% FS/year
• Armored K-type thermocouple (φ1.6 mm), temperature resolution 0.1 °C
• Built-in exhaust gas treatment: expansion tank + neutralizing scrubber + exhaust fan for safe handling of acidic combustion by-products

Enhanced Laboratory Safety & Convenience

• Multiple safety features: pressure relief ports, high-pressure solenoid valves (≥1.6 MPa, response ≤10 ms), dual manual/automatic vacuum modes
• Purge verification using paramagnetic oxygen analyzer + nitrogen residue cleaning cycle
• Compact design optimized for standard laboratory benches