On October 11, 2021, the State Administration for Market Regulation and the State Standardization Administration approved the release of GB/T 9098-2021 "Fully Enclosed Motor-Compressor for Refrigerators". The standard is revised on the basis of GB/T 9098-2008, mainly adding R290 working fluid related test methods and judgments, modifying the energy efficiency coefficient and noise classification of R600a working fluid products, increasing the test conditions and reliability test methods of inverter compressors, updating the reference of relevant standards, and more in line with the current development trend of the refrigerator industry. The standard will be implemented from May 1, 2022.
The revision work has attracted much attention
The current standard GB/T 9098-2008 has been released and implemented for more than ten years, and it has been unable to meet the needs of the current market. As the "heart" of the refrigerator, the performance improvement of the compressor has an important impact on the development of the whole machine product, so the revision of the standard is very necessary.
In the past 10 years, the rapid development of the refrigerator industry has promoted the iterative update of refrigerator compressors round after round, especially under the strong impetus of the "energy saving and emission reduction" policy, not only the energy efficiency level and performance of fixed speed compressors have been greatly improved, but also the frequency conversion compressor technology has gradually matured, and it has occupied a very large market share.
With the inclusion of hydrofluorocarbons (HFCs) with extremely high greenhouse effect potential values on the list of controlled substances, the environmentally friendly and energy-saving R290 is increasingly being used in refrigerators. However, the current standard GB/T 9098-2008 not only does not have the relevant experimental content of the inverter compressor, but also has a gap in the R290 working fluid related test methods and judgments, which can no longer meet the requirements of the current technology.
Not only that, but the refrigeration capacity test conditions in the current standard have also lagged behind. According to the relevant person in charge of Garcibela, China, as a big producer of refrigerator compressors, will export products to all parts of the world with large differences in climatic conditions. However, the current standard in the refrigeration capacity test conditions have always quoted the American ASHARE conditions, and there are certain differences with the actual working conditions used in the refrigerator, and a working condition point cannot fully objectively reflect the refrigeration effect of the compressor.
Therefore, the industry is full of expectations for the revision of GB/T 9098-2008. In 2019, when the revision of the standard was launched, it not only received the attention and participation of compressor companies such as Garcibela, Huangshi Dongbei and Qianjiang, but also many machine manufacturing enterprises, such as Changhong Meiling, Haier, Hisense and Midea, etc., also actively participated in the revision of the standard.
Finally, after several rounds of discussion, collation and revision by the standard drafting working group, the "Fully Enclosed Motor-Compressor for Refrigerators" was formed in March 2021 and officially released on October 11. The revised standard applies to fully enclosed motors-compressors used in low-back pressure household and similar refrigeration appliances with low back pressure of R600a, R134a and R290, and the cooling capacity of applicable products is also extended from no more than 400W to no more than 500W.
Follow the trend of energy saving, environmental protection, high efficiency, frequency conversion and low noise
Following the pace of development of the refrigerator industry, the revision of the standard follows the industry development direction of "energy saving, environmental protection, high efficiency, frequency conversion and low noise", and revises the relevant technical requirements and indicators.
With the proposal of the "double carbon" goal, energy conservation and emission reduction have become the general trend, and the refrigerator industry has continued to develop in this direction. According to Zhang Bao, deputy chief engineer of Qianjiang Compressor, gb/T 9098-2021 has improved the energy efficiency level of refrigerator compressors in terms of energy saving and high efficiency. In the refrigerator industry, R600a working fluid products are still the mainstream, after more than ten years of development, product energy efficiency indicators have been greatly improved, the standard revision in the reference to the actual level of the compressor manufacturers on the basis of further improve the energy efficiency level of the product. The energy efficiency level in this standard is expressed in terms of the performance coefficient (COP), which is the ratio of the cooling capacity to the power consumed by the refrigeration when the compressor is connected to the refrigeration system.
It is worth mentioning that the compressor nominal performance coefficient (COP) classification of R600a and R134a refrigerants in the current standard is different. However, due to the fact that refrigerators and freezers follow the unified energy efficiency requirements, after this revision, the energy efficiency level of GB/T 9098-2021 is implemented according to the unified requirements, and refrigerants are no longer distinguished. Among them, the nominal performance coefficient of the compressor under standard working conditions is divided into four energy efficiency levels according to the level of value. Class A is the highest energy efficiency level, D class is the lowest energy efficiency class, and the frequency conversion compressor is divided according to the performance coefficient of the best performance coefficient speed (frequency), and the specific indicators are shown in Table 1.
At the same time, for the actual working conditions of the refrigerator, GB/T 9098-2021 also increases the test requirements of the compressor under the actual working conditions of the refrigerator to better provide a design reference for the optimization of energy consumption for refrigerator manufacturers.
In terms of environmental protection, the standard adds the relevant test methods and judgments of the natural working fluid R290. This is also one of the highlights of this revision of the standard. Zhang Bao told the "Electrical Appliance" reporter that due to the increasing application of R290 in the field of refrigerators, this revision adds R290 working fluid as the basic working medium of the standard, and stipulates the corresponding test methods, product energy efficiency, noise and vibration. Among them, the start-up performance test balance pressure, noise test conditions, 500 hours and 1000 hours accelerated life test conditions, start-up durability test conditions and other aspects have added R290 related content.
The addition of relevant content of inverter compressors is also a major change in the revision of the standard. Xia Tai'an, a standardization engineer at Huangshi Dongbei, said that in the refrigerator industry, inverter compressors have been rapidly popularized, and the test methods and judgment standards in the current standards have been unable to meet the requirements. Therefore, the revision adds the test conditions and reliability test methods of inverter compressors.
Noise is the most intuitive indicator of refrigerator consumers, so low noise is an important development trend in the refrigerator industry in recent years. If the user's somatosensory requirements continue to increase, the noise level of the refrigerator compressor also needs to improve year by year. The current standard divides different noise levels for different refrigerants, and products with different cooling capacities only propose a limit value. This noise limit requirement, has not adapted to the current development status of the industry, GB/T 9098-2021 for all refrigerants using unified noise requirements at the same time, the vibration index requirements have also been improved, before the R134a refrigerant compressor noise limit has become the minimum level limit of compressor noise classification. Specifically, GB/T 9098-2021 divides the nominal noise value of the compressor into four levels according to the level of noise value, including A class, B class, C class, and D class, A class is the best level of noise, D class is the lowest level of noise of various types of compressors, and the measured noise value of the compressor should not be greater than the specified value of D level. The inverter compressor is divided according to the best performance coefficient speed (frequency) noise value of the rated speed (frequency), and the specific indicators are shown in Table 2.
It is not difficult to meet the standards
Compared with the current standard, GB/T 9098-2021 has a lot of revised content, and there are 24 major technical changes mentioned in the preface alone.
Under such a big change, is it difficult for compressor companies to meet the requirements of this standard? "Electrical Appliances" reporter learned through interviews that because the standard is a national standard, the requirements for various indicators will not be particularly high, and for most enterprises, it is not difficult to meet the standards. "However, some small and medium-sized enterprises that do not pay attention to product development and innovation will have certain difficulties in meeting the standards, and even after the implementation of the new standard, it is difficult to achieve high-performance requirements." A representative of a mainstream compressor company said bluntly.
For the significance of the revision of the standard, the relevant person in charge of Garcibela said that the standard starts from the existing technical development level and user experience of the refrigerator compressor, and the content is in line with the relevant international standards, which can lead the development of the industry, and will play a positive guiding role in the future technology research and development of the refrigerator compressor industry and the promotion of green energy-saving and low-carbon environmental protection technology.
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