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More refined industry standards for low-pressure pump pipes will be introduced
Source: | Author:佚名 | Published time: 2021-05-20 | 163 Views | Share:

In recent years, while China's low-pressure pump and pipe industry has been continuously growing, it has also revealed a series of problems that threaten the healthy development of the industry. The industry also expects to regulate market order by formulating detailed industry standards.

In March of this year, Zhejiang East China Steel Industry Group Co., Ltd., the chairman of the Yangtze River Delta Coated Metal Sheet Industry Association, jointly prepared the draft for soliciting opinions on the industry standards of "Continuous Hot Dip Galvanized Steel Plates and Steel Strips for Construction" and "Colored Coated Steel Plates and Steel Strips for Construction", in collaboration with the Institute of Metallurgical Industry Information Standards and other units.

Although China has already issued two national standard documents, GB/T2518-2008 and GB/T12754-2006, for continuous hot-dip galvanized steel plates and steel strips, as well as color coated steel plates and steel strips. However, the standards are relatively broad, which has led to a very small number of enterprises exploiting the "loopholes" in national standards, causing market chaos; There have also been many trade disputes in international and domestic trade. At present, the low-pressure pump pipe industry is soliciting opinions on the industry standard nationwide.

The quality of domestic low-pressure pump pipes is worrying, and a "price war" is prevalent

In the past decade or so, the domestic low-pressure pump and pipe industry has been in a state of "crazy" expansion, accompanied by rapid economic growth, as well as the rapid increase in production and demand in industries such as construction, automotive, and home appliances. The entire market has gradually shifted from supply less than demand to supply more than demand, and now there is even overcapacity.

As of the end of 2012, according to incomplete statistics, the design production capacity of hot-dip galvanizing and color coating in China reached 65 million tons and 43 million tons respectively, with year-on-year growth rates of

8.7% and 9.8%, although the growth rate has dropped to a new low in recent years, the overall production capacity is still continuously increasing.

Therefore, the supply pressure and product homogenization issues in the low-pressure pump pipe market have increased without decreasing. The price war between low-pressure pump pipe steel mills is also inevitable. While constantly seeking low costs, steel mills sometimes even sacrifice product quality by thinning the zinc layer on galvanized steel coils. It is reported that the thickness of the zinc layer on galvanized steel coils produced by some low-pressure pump pipe steel mills in China is only one sixth, or even one ninth, of the European standard.

In addition, some domestic enterprises currently lack comprehensive technical guidance in their product requirements, and the quality of their products cannot reach a high level. A very small number of enterprises even take advantage of loopholes in national standards, intentionally producing substandard products, causing market chaos.

Shen Weigen, the President of Zhejiang East China Light Steel Building Materials Co., Ltd. and the President of the Yangtze River Delta Plating and Coating Metal Thin Plate Industry Association, once admitted to Steel Union Information that in the current domestic low-pressure pump pipe industry, there is a common situation where low-pressure pump pipe steel plants continuously reduce the thickness of coatings and coatings in order to reduce costs, and use inferior coatings, which seriously affects product quality and poses a serious threat to the healthy development of the industry.

The national standard is too broad and often leads to trade disputes.

As the domestic low-pressure pump pipe industry continues to develop and grow, China has successively issued two national standard documents, GB/T2518-2008 and GB/T12754-2006, for two varieties: continuous hot-dip galvanized steel plate and steel strip, and color coated steel plate and steel strip.

In the GB/T12754-2006 document, the corrosiveness of the usage environment is divided into three categories: low, medium, and high, and the substrate coating thickness of the color coated plate coil is clearly specified. Among them, using hot-dip galvanizing as the substrate, when the corrosiveness of the usage environment is low, the minimum zinc layer needs to reach 90g per square meter; Using hot-dip galvanized iron alloy as the substrate, the minimum coating is 60g per square meter; Using hot-dip aluminum zinc alloy as the substrate, the minimum requirement for coating is 50g per square meter; The hot-dip galvanized aluminum alloy is 65g per square meter.

In addition, GB/T12754-2006 stipulates that the thickness of the front coating should not be less than 20um; When the reverse coating is one layer, its thickness should not be less than 5um, and when the coating is two layers, its thickness should not be less than 12um.

It is reported that China's standards are formulated based on relevant foreign standards. Most foreign production enterprises are large and advanced, with strong self-discipline. Detailed technical requirements are customized and inspected by the enterprises themselves. However, there is still a certain gap between China's actual situation and that of foreign countries, which has led to a very small number of enterprises taking advantage of loopholes. It is precisely because the national standards and technical requirements are not sufficiently constrained that there have been many trade disputes in the international and domestic trade of low-pressure pump pipe products in China. For example, due to the lack of requirements for the corrosion resistance of galvanized steel plates after surface treatment in national standards, some companies have caused oxidation of their products during transportation, but customers cannot receive compensation. Not only has it caused a large number of quality objections, but it has also affected the popularity of the entire industry.

Refine product quality constraints in multiple aspects through branding refinement

In response to the current situation of China's low-pressure pump pipe industry, Zhejiang East China Steel Industry Group Co., Ltd., the chairman unit of the Yangtze River Delta Plating and Coating Metal Sheet Industry Association, as the initiator, has collaborated with the Institute of Metallurgical Industry Information Standards and other units to prepare the "Continuous Hot Dip Galvanized Steel Sheet and Strip for Construction" (hereinafter referred to as the "Hot Dip Galvanization Opinion")

The draft for soliciting opinions on the industry standard of Color Coated Steel Plates and Strips for Construction (hereinafter referred to as "Color Coating Opinions") was released in March this year.

It is reported that the industry standards will be revised around principles such as practicality, fair trade, and comprehensive constraints, and modifications will be made to meet market demand based on the different uses of hot-dip galvanizing and color coating.

In the "Opinions on Color Coating", it can be found that the corrosiveness of the environment used in the weight of the coating is divided into very low, low, medium, and high, with more "very low" standards compared to national standards. Among them, using hot-dip galvanizing as the substrate, when the corrosiveness of the usage environment is very low, the minimum zinc layer needs to reach 30g per square meter; Using hot-dip aluminum zinc alloy as the substrate, the coating is required to be 20g per square meter at a very low temperature; The hot-dip galvanized aluminum alloy is 30g per square meter.

At the same time, the thickness of the front coating is also divided into three levels: thin, medium, and thick, and the coating thickness is specified to be no less than 15, 20, and 25um, respectively. The drafter of the standard stated that this is a regulation made based on the actual situation in China, which requires clear explanations in product labeling and quality assurance documents to ensure fair transactions.

In addition, colored coated steel strips are commonly used to make sandwich panels, which have special requirements for the adhesive properties of the back paint. However, they are not taken into account in national standards, and the requirements and measurement methods for adhesive properties will be clearly specified in the compiled industry standards.

In the "Opinions on Hot Dip Galvanization", it can also be found that various standards are more refined, such as dividing chromic acid passivation into light passivation, general passivation, and heavy passivation, and dividing surface oil treatment into light oil, general oil, and heavy oil, as well as specifying the requirements for salt spray resistance test after surface treatment, in order to ensure the quality of the product. Especially, this standard has made requirements for the adhesion of coatings, changing the guiding principle of the national standard that thicker galvanized coatings have better corrosion resistance, which is beneficial for saving precious metals.

The industry expects a new industry standard for low-pressure pump pipes. On the one hand, preventive measures can be taken to eliminate customer complaints, protect customer interests, and enable customers to benefit from it. On the other hand, market order can be regulated, so that both supply and procurement parties have a basis to rely on, and the low-pressure pump pipe industry can enter a reasonable and orderly competitive state, achieving a win-win effect.