Nuclear power plays an important role in the world's energy mix. At present, the world has more than 30 countries and regions have nuclear power plants, by 2030 years ago, it is estimated that 10-25 new countries will join the nuclear "club" and the new nuclear power plant. So far, there are 30 nuclear power units are running, is expected over the next 10 years, China will build at least six new nuclear power units each year.
Due to the need for a huge water source to cool the generator, most of the nuclear power plants are built at the seaside, partly in the vicinity of the river or the Great Lakes. In the past, the cooling water pipelines of nuclear power units were made of carbon steel, but because of their perishability, the service life was limited, so began to consider the use of polyethylene pressure pipe instead of carbon steel pipe used in nuclear power plant hot and cold water exchange system.
In 1995, the United States began to test the operation of the polyethylene pressure pipeline in the field of low pressure transmission, in 2007 began to develop the corresponding nuclear power polyethylene pipe standard specifications - ASME BPVC N-755-1,2009 year raised arms in the United States To be applied. At present, the polyethylene pipe in China's nuclear power plant has not yet officially applied, but the past two years have plastic pipe production enterprises and domestic nuclear power companies and have their polyethylene pipe pressure in the application of nuclear power plant recognition. Polyethylene piping is now undergoing the relevant test evaluation work, is expected this year there will be a polyethylene pressure pipe is officially used in domestic nuclear power unit cooling water exchange system.
Each nuclear power plant takes about a few kilometers of hot and cold water exchange system piping, most of which is a large diameter thick-walled polyethylene pipe. Nuclear power requirements of the security level is very high, how to ensure that the polyethylene pipe pressure on the safe and effective operation of nuclear power has become a major issue.
At present, the requirements for polyethylene pressure piping for domestic nuclear power are basically adopted in the American standard system. The size series of the pipeline system is in English, and the most important standard is ASME BPVC (N-755-1, developed by the American Society of Mechanical Engineers' Boiler and Pressure Vessel Standards Committee) specification.
N-755-1 specified nuclear power polyethylene pipe with a maximum diameter of up to 64in. (1600mm), the size of the series were DR7, DR9, DR11 and DR13.5 four. The United States has 36in. (900mm), DR9, wall thickness of more than 100mm polyethylene thick pipe in the practical application of nuclear power plants. Now, the country has been able to produce wall thickness of more than 100mm quality qualified large diameter pipe. We believe that we can produce large-diameter thick-walled polyethylene pressure pipes that meet the requirements of high nuclear power requirements in the production of polyethylene raw materials and equipment manufacturers, pipe and pipe fittings enterprises, as well as scientific research institutions and pipeline testing units. The development of the plastic pipe industry at the same time to promote the overall progress. In the future, polyethylene pressure pipeline in the field of nuclear power application prospects.
