Vertical Flame Spread Test Machine Of Vertically Bunched Wires Or Cables IEC 60332-3-10

Introduction:

The Bunched Cable Vertical Flame Tester is a specialized test device used to evaluate the ability of bundled cables or optical cables to resist vertical flame spread when installed vertically. It is a key and mandatory instrument for flame retardancy testing in the cable industry and is widely used by cable manufacturers, third-party quality inspection agencies, research institutes, and the power and communications sectors.

This instrument simulates the harsh conditions of bundled cable combustion in a real fire to scientifically and accurately assess the flame retardancy rating of cables, providing crucial data support for ensuring fire safety in critical areas such as public spaces, high-rise buildings, and subway tunnels.

Standards:

● GB/T18380.31,32,33,34,35,36:2022；
● IEC60332—3—10,22,23,24,25:2018；

Working Principle:

The core principle of Vertical Flame Spread Test Machine Of Vertically Bunched Wires Or Cables is to bundle cable samples of a specified length and number and mount them vertically within a large metal test chamber. A trapezoidal propane gas blowtorch with a specified power (e.g., 20.5 kW or higher) applies a flame from the bottom of the sample for a specified time (e.g., 20 minutes or 40 minutes). After the flame extinguishes, the distance of the charred cable is measured to assess its flame retardancy.

Evaluation Criteria: The lower the flame spread, i.e., the shorter the charred distance, the better the flame retardancy of the cable. The standard specifies different categories, such as A, B, C, and D, corresponding to different sample sizes and burning times. The acceptance criterion is that after combustion ceases, the distance between the furthest point of the charred portion and the center of the blowtorch bottom should not exceed 2.5 meters.

Main Features of ​Vertical Flame Spread Test Machine Of Vertically Bunched Wires Or Cables:

Test Chamber:
The test chamber is stainless steel, filled with a mineral wool box. A high-temperature-resistant glass observation window is located on the front for real-time observation of the test process. An air intake space is located 150 mm from the front wall at the bottom of the chamber, and an exhaust space is located at the top.

Sample Ladder System:
The equipment is equipped with two steel ladders of different sizes: 500 mm (W) × 3,500 mm (H) and 800 mm (W) × 3,500 mm (H) for securing and supporting bundled cable samples. The ladder dimensions and sample mounting method vary depending on the test category (A/B/C/D).

Burner System:
Two standard propane strip burners.
Two Venturi gas mixing units.
A pressure gauge and pressure-reducing valve are provided, allowing for adjustable propane and air pressures to 0.1 MPa.
Gas Source Control and Regulation: Air flow is adjustable from 10 to 100 L/min using a rotameter, and propane flow is adjustable from 2 to 20 L/min using a rotameter.

Automatic ignition device: Enables remote, safe ignition. Automatically sets the combustion test time and automatically cuts off the gas supply when the time expires.
The top of the chamber is equipped with a forced fire sprinkler system.
The upper portion of the specimen steel ladder is equipped with an automatic lifting device.