In recent years, the development of cast-in-place and heat-insulating aluminum doors and windows has been rapid, with an increasing market share. In 2004, the China Non-Ferrous Metals Standardization Technical Committee introduced the national standard "Aluminum Alloy Building Profile Part 6: Insulation Profile," commonly known as GB5237.6, specifically for cast-in-place insulation profiles. This standard was designed to evaluate the performance of thermal insulation materials used in these profiles.
When testing according to GB5237.6, the most common approach is to focus on the tensile strength and shear resistance of the insulating material at normal and extreme temperatures. However, this method often overlooks the physical properties of the insulation itself, which can lead to an incomplete assessment. To address this issue, in 2012, under the leadership of the China Non-Ferrous Metals Standardization Technical Committee, Yasong Polyurethanes (Shanghai) Co., Ltd. and the National Chemical Building Materials Testing Center collaborated to develop a new set of standards for heat-insulating rubber. These were incorporated into the "Aluminum Alloy Building Profiles Assistive Materials" series, specifically Part 2: Polyurethane Heat-Insulating Adhesive Material, officially named GB/T 23615.2, which came into effect in 2013.
GB5237.6 primarily focuses on the wind pressure resistance and long-term shrinkage of cast-in-place insulation profiles. One of the key technical indicators is the shear resistance of the insulation profile. On the other hand, GB/T 23615.2 emphasizes the intrinsic properties of the heat-insulating adhesive, such as impact resistance, machinability, and applicability. Among these, the notched Izod impact strength and elongation at break are particularly important. Even if a profile passes all the tests required by GB/T 23615.2, it does not necessarily mean it is completely safe. The actual safety of the profile depends on whether the heat-insulating adhesive used also meets the standard requirements.
The notched Izod impact strength test is especially critical because it directly determines whether the profile might become brittle or deformed over time. Even if the shear resistance is acceptable, poor impact resistance could lead to cracks, deformation, or even safety accidents. Therefore, when selecting cast-in-place profiles, it's essential not only to request the profile’s inspection report but also to ask for the insulating glue’s test results or to obtain samples for independent testing.
For a long time, there was no unified standard for identifying heat-insulating materials. The introduction of GB/T 23615.2 has helped resolve this issue by setting clear guidelines for testing, packaging, and quality certification of polyurethane heat-insulating adhesives. This gives manufacturers and users a reliable benchmark for assessing the quality of insulation materials.
Polyurethane insulation testing includes two main parts: original glue testing and insulation rubber sheet testing. The former involves checking appearance, solidification time, and other characteristics, while the latter includes tests like density, load deformation temperature, thermal conductivity, notched Izod impact strength, hardness, tensile strength, and UV aging resistance.
Among all the tests, the notched Izod impact strength is the most crucial. This destructive test measures how much energy a material absorbs before breaking, helping to assess its toughness and brittleness. If the impact resistance is insufficient, the profile may crack or deform, leading to potential safety hazards.
If you are purchasing or using cast-in-place insulated profiles, it is highly recommended that you request the latest impact strength report from the National Chemical Building Materials Testing Center. If the supplier cannot provide it, ask for a sample of the insulation rubber for independent testing. The cost for such a test typically ranges between 200–300 RMB.
Here is a list of testing organizations across China that can perform the notched Izod impact strength test:
- **North China**: Beijing Research Institute of Chemical Industry, No.14 North East Third Ring Road, Beijing
- **Chengdu/Chongqing**: Tongbiao Standard Technical Service Co., Ltd. Chongqing Branch
- **Suzhou, Jiangsu**: Suzhou Branch, Tongbiao Standard Technical Service Co., Ltd.
- **Wuhan**: Wuhan Branch, Tongbiao Standard Technical Service Co., Ltd.
- **Shanghai**: Shanghai Tongbiao Standard Technical Service (Shanghai) Co., Ltd.
- **Hangzhou/Ningbo, Zhejiang**: Zhejiang Provincial Institute of Chemical Analysis and Testing Center
- **Changsha, Hunan**: Tongbiao Standard Technical Service Co., Ltd. Changsha Office
- **Fuzhou/Xiamen, Fujian**: Fuzhou and Xiamen branches of Tongbiao Standard Technical Service Co., Ltd.
- **Guangzhou, Guangdong**: Guangzhou Branch, Tongbiao Standard Technical Service Co., Ltd.
- **Shanghai**: Yasong Polyurethanes (Shanghai) Co., Ltd. – Contact: Miss Ho, Tel: *501
By ensuring that both the profile and the insulation material meet the required standards, you can significantly reduce the risk of structural failure and ensure long-term safety.
(Environmentally friendly)low noise local ventilation fan
Explosion-Proof Low Noise Ventilation Fan for Mine,Low Noise Mining Local Mine Fan,Low Noise Coal Mine Ventilation Fans
Yuncheng Anhong Enery-saving Explosion-proof Fan Co.,Ltd. , https://www.anhongfengji.com