Most of the water pipes used in modern architecture are concealed, such as pipe wells, so once the pipe material is chosen wrong, the trouble costs may be calculated in multiples. Therefore, the selection principle of water supply pipe is energy saving, recyclable, safe and reliable, economical and sanitary. Only the pipes meeting these principles are really good pipes. Commonly used water supply pipes are mainly stainless steel pipes, copper pipes, galvanized pipes, composite pipes and plastic pipes, etc.. Here, from the point of departure to compare the stainless steel pipe and other commonly used water pipe.
Comparison of strength between stainless steel pipes and other water supply pipes
The most commonly used stainless steel pipes in the water industry are 304 and 316 stainless steel, both of which meet the vast majority of water treatment and delivery conditions.
The tensile strength of 304 stainless steel pipes is 2 times of that of ordinary steel pipes, 3 times of that of copper pipes, and 8 times that of plastic pipes, 10 times as much as 4 times. The strength of material selection determines whether the water pipe is strong, collision resistant and safe. Because it is safe and reliable, it is the most important requirement of building water supply pipe. When subjected to external force, the possibility of leakage of stainless steel pipe is very small, but the possibility of leakage of copper pipe and plastic pipe is relatively high, and it is easy to be damaged by construction or two decoration. In general, the main reason for the plastic pipe complaints is leakage, and the leakage is due to plastic pipes can not withstand external impact damage.
In addition, the work pressure of high-rise water supply system is generally higher than 0. 6Mpa, higher pressure requirements for pipes. The working pressure of the plastic pipe is smaller than that value, so it does not meet the requirement. But the expansion coefficient of the composite pipe is different greatly. If the bond is not firm or the temperature changes greatly, it is easy to produce the separation layer. Thin-walled copper pipe pressure up to 5. 9Mpa, and thin-walled stainless steel pipe because of mechanical performance is good enough to withstand high water pressure, can reach more than 10Mpa, especially for high-rise water supply.
Many world famous buildings now adopt stainless steel pipes as main water supply pipelines. For example, the Beijing Great Hall of the people, Chinese many high-rise buildings, Shenzhen, great Kingkey 100 100 storey building, the Olympic Games and Asian Games Universiade projects, more than 80% of the National Hospital, four-star five star hotel with stainless steel pipe as a water supply pipeline.
Comparison of thermal expansion performance and thermal insulation performance ofstainless steel pipes
The coefficient of thermal expansion of the stainless steel pipe is similar to that of the copper pipe. It is 1.5 times of that of the ordinary steel pipe, and the stainless steel pipe has the characteristics of thermal expansion and cold contraction. Plastic pipe expansion coefficient is too big, is its fatal shortcoming, not suitable for hot water pipe. In the condition of environmental temperature changes, plastic pipes are prone to leakage and other hidden dangers, especially in concealed projects. There are two kinds of materials with different expansion coefficient in the composite pipe. The cracks between the two materials are easy to crack and cause the water pipe to burst. The heat conductivity of stainless steel pipe is 1/25 of copper pipe, 1/4 of ordinary steel pipe. It is very suitable for conveying hot water, and its insulation performance is much better than copper pipe.
Comparison of corrosion resistance between stainless steel pipes and other water supply pipes
Stainless steel pipe is one of the most prominent advantages of its corrosion resistance is excellent, is the five kind of pipe is the best. Because the stainless steel can and oxidant inactivation, forming a layer of dense tenacity the chromium oxide protective film on the surface of stainless steel, can effectively prevent further oxidation reaction. But other metal pipe, such as galvanized pipe, copper pipe passivation capacity is very weak, lead to galvanized pipe or copper pipe corrosion resistance is far lower than stainless steel pipe.
Stainless steel will not happen even if carbon steel corrosion, so no need to use additional protective coating, stainless steel pipe, chemical composition of water is not restricted, because all kinds of stainless steel in PH and hardness of the oxygen content, temperature, water has very good corrosion resistance, stainless steel pipe can withstand high velocity, even the flow rate is greater than 40 m / sec, still maintain a very low corrosion rate, less than 0.003 mm / year, especially for high-rise water supply.
Stainless steel generally does not occur localized corrosion, 304 stainless steel can tolerate chloride content of 200ppm, 316 stainless steel can tolerate chloride content of up to lOOOppm, and the conclusion is a scientific basis for verification.
Comparison of sanitary and environmental performance of stainless steel pipes
The stainless steel water pipe has the advantages of excellent sanitary performance, no additional water pollution problems, no peculiar smell, no scaling, no harmful substance precipitation, and can keep the water quality pure and harmless to human health. The stainless steel material itself is non-toxic, clean and good, has long been used in various fields related to human health, so not only in the food industry including dairy, beverage, brewing, pharmaceutical industry, and other industries and long-term use of tableware utensils become the standard timber industry, but also widely used in material safety and the cleaning requirements of high medical body implants such as various stents, artificial joints and steel nail body, and become the standard timber requirements for cleanliness of clean room of semiconductor industry’s extreme. With the continuous improvement of water quality requirements and laws and regulations, the restrictions on the release of pollutants in water pipes are becoming increasingly stringent. The best pipes for transporting high-quality drinking water are stainless steel.
In addition, the service life of stainless steel pipe is the longest. From the analysis of the use of stainless steel abroad, the life of stainless steel pipe can reach 100 years, and less has 70 years, as long as the life of the building. The composite pipe material life and life is influenced by thermal expansion and restriction, and composite pipe because of two materials together with the possibility of shedding greatly, also affect the life of. The life of plastic pipes is difficult to determine in China, and depends largely on the production process technology and raw material quality, and the quality is uneven
Source: China Stainless Steel Pipe Manufacturer – Yaang Pipe Industry Co., Limited (www.yaang.com)