The thermal conductivity of polyurethane is lambda= 0.013-0.03kcal/m.h.oC, which is much lower than other commonly used pipeline insulation materials, and the thermal insulation effect is increased by 4-9 times. In addition, its water absorption is very low, about 0.2 kg/m 2. The reason for low water absorption is that the obturator rate of polyurethane foam is as high as 92%. Low thermal conductivity and low water absorption, together with high-density polyethylene or FRP protective shell, have good insulation and external waterproofing, changing the traditional ditch laying heating pipe "wet cotton quilting" conditions, greatly reducing the heating pipe. The overall heat loss of the heating network is 2%, which is much lower than 10% of the international standard. 2. Low heat loss and energy saving. According to the calculation of relevant departments, polyurethane insulation steel pipe can generally reduce project cost by 25% (using FRP as protective layer) and 10% (using high density polyethylene) as protective layer. 1. Advantages of polyurethane insulating pipes in reducing engineering cost:


External anticorrosive coating for petroleum pipeline. In December of the same year, China Petroleum Infrastructure Bureau, Pipeline Bureau, Sichuan Petroleum Design Institute, Northwest Pipeline and Command Experts jointly organized a group of pipeline painting systems to the United States, Italy and many other pipelines. China Petroleum and Natural Gas Corporation decided to introduce 3PE coating operation and coating technology for Shaanxi-Beijing natural gas pipeline and Library in summer of 1994.


Production enterprises should not participate in disorderly competition and malignant competition at lower cost; continue to promote the lead-free work of PVC-U pipeline; strengthen the factory inspection and production of inferior products in the application field, and guide the regulation of market behavior. Compared with other traditional pipelines, it is necessary to improve the technical level, quality level, product grade and competitiveness.


Hunan LSAW Seamless Steel Tube Factory is of the highest service. On December 9, after listening to the general situation report of the education practice activities of the Hebei Provincial Committee's Mass Line, it was emphasized again that the production capacity of seamless steel tubes should be greatly reduced and pollution control should be controlled. In the medium and long term, seamless steel pipe production capacity will return to a reasonable range, the contradiction between supply and demand will be eased, which is conducive to the stability of the steel market. Seamless steel pipe theoretical weight table: windfall profits have gone far, the current situation in cracks is growing.



It is suitable for transportation of corrosive oil or high temperature conditions by using large diameter steel tube insulation pipe. Seamless steel pipe is divided into hot rolling and cold drawing. Due to the hardening of materials by cold drawing process, the pipelines used in oil pipelines are mainly carbon steel pipes, which can be divided into seamless steel pipes and welded steel pipes according to the manufacturing process. The seamless steel pipe has the characteristics of high strength and large specification. The development of pipes and the applicable materials and specifications of power technology, and related technologies have been widely used in pipeline transportation of petroleum products. [3]



Zhejiang water supply black insulating pipe manufacturer, in the early 1980s, 3PE anticorrosive steel pipe was first widely used in Europe, well received by users, is the use of a large number of pipeline coating system. In the summer of 1994, CNPC decided to introduce 3PE coating operation and coating technology for the external anticorrosive coatings of North Shaanxi natural gas pipeline and Kuqin oil pipeline to be started. In December of the same year, experts from China Petroleum Infrastructure Bureau, Pipeline Bureau, Sichuan Petroleum Design Institute and Northwest Pipeline Command Team went to the United States, Italy, Turkey and other countries to inspect the 3PE coating line. In May 1995, Liaohe Petroleum Construction Company was responsible for Canadian Root Labor Company's bidding and importation of China's 3PE painting line. It was put into normal production at the beginning of 1996. In 1996, the Suzhou Anti-Corrosion Plant jointly established by Soksam Company of Italy and No. 6 Plastic Plant of Harbin put into normal production in May. The 3PE coating line imported from the Netherlands by Northwest Pipeline Command and Hong Kong Commercial Joint Venture Company was completed and put into operation in Ba in 1996.