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Test method for fabric thermal protection (radiation) performance tester
2024/11/15
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The fabric thermal protection (radiation) performance tester is used to measure the thermal radiation performance of single or multiple layers of fabric in a high-temperature environment, and can also be used to measure the thermal insulation performance of other fire-retardant panels.
As a modern technology enterprise integrating R&D, manufacturing, sales, training, and service, Standard Group (Hong Kong) Co., Ltd. is committed to delivering more testing instruments to the market, providing testing instruments for textiles, leather, combustion, automotive interior and exterior trims, material environmental climate aging, etc., and non-standard customization is also acceptable. Before purchase, targeted tests can be carried out according to customer requirements to ensure that the purchased instruments are suitable.
Application significance:
Thermal radiation performance is an important performance indicator of flame-retardant products. Measuring its protective performance is important for selecting materials, researching and developing new products, and improving processing technology.
Applicable standards:
ISO 6942-2002(EN366)
Test method:
1. Thermal convection
Convection heat dissipation is the transfer of heat with the movement of fluids such as liquids (such as water) or gases (such as air). The way of transferring heat by causing fluid movement due to uneven fluid temperature is called natural convection. Natural convection exists in the air in the boundary layer of the human body and clothing surface. Forced convection is the heat transfer caused by fluid movement due to other external reasons. The anti-heat convection performance of fabrics is closely related to the weight, density, and gas properties of the fabric. Increasing the weight of the fabric can increase the time required to cause second-degree burns. At the same time, multi-layer fabrics have better anti-heat convection effects than single-layer fabrics.
2. Heat conduction
Heat conduction refers to the transfer of heat along an object. It is transferred from a high-temperature object to a low-temperature object. This transfer is mainly achieved through continuous collisions between adjacent molecules in a substance. In the application of thermal protective clothing, heat conduction refers to the heat being carried by sparks, molten metal sprays, etc., contacting clothing and transferring heat through clothing to the human body, thereby causing damage to the human body.
Usually, the anti-molten metal thermal conductivity performance of fabrics can be measured by placing artificial skin made of standard PVC film behind the fabric and measuring the damage caused to the synthetic skin by the heat of molten metal passing through the fabric. According to the area and degree of damage, the quality of the thermal protection performance of fabrics can be divided into one to seven levels. Level 1, no injury; Level 2 and Level 3 are first-degree burns with an injury area of less than or greater than 0.01 square meters; Level 4 and Level 5 are second-degree burns with an injury area of less than or greater than 0.01 square meters; Level 6 and Level 7 are third-degree burns with an injury area of less than or greater than 0.01 square meters.
3. Thermal radiation
Thermal radiation refers to the heat radiated outward from an object along a straight line. The essence of thermal radiation is the heat radiation caused by the temperature of an object, and its magnitude is proportional to the fourth power of the temperature of the heat source. Unlike heat conduction and heat convection, thermal radiation is a non-contact heat transfer method that does not require any material as a medium but transfers heat in the form of electromagnetic waves. In the actual application of thermal protective clothing, thermal radiation is one of the main forms of heat transfer that causes damage to victims. Even in combustion with flames, up to 80% of its energy includes thermal radiation.
In the test of the thermal radiation protection performance of thermal protective clothing, the fabric is often exposed vertically to a radiant heat source. Within a specified distance, the heat source radiates heat to the fabric sample. The thermal radiation protection performance of the sample is evaluated by measuring the time and heat flux density required to cause second-degree burns on the human skin behind the sample.
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