The cold working methods of steel pipes mainly include cold drawing and cold rolling. The raw materials of cold-rolled steel pipes can be hot-rolled seamless steel pipes or Welded Pipes. The common characteristics of the cold working method of steel pipes are high dimensional accuracy and good surface roughness. It can produce very thin (up to 0.05~0.01mm) thin-walled tubes and very thin (up to 0.3~0.1 mm in diameter) capillaries.
Seamless Steel Pipe is a kind of pipe with hollow section, which is widely used to transport fluids, such as oil, natural gas, gas, water and some solid materials. Compared with solid steel such as round steel, steel pipe is light in weight when its bending and torsional strength is the same. It is a kind of economic Section Steel, which is widely used in pipeline engineering.
Cold Drawn Seamless Steel Pipe,Seamless Cold-Drawn Steel Tubes,Seamless Cold Drawn Pipe,Cold Drawn Steel Pipe SHANDONG HUITONG STEEL CO.,LTD , https://www.cnmetalsupply.com
The China Automobile Association has submitted to the relevant departments the proposal for the scientific implementation of the four standards for heavy-duty vehicles. The relevant departments are coordinating and will soon have results.
The four standards for heavy-duty vehicles originally scheduled to be implemented on July 1 will be delayed again. Prior to this, the implementation time of the National IV emissions has been postponed from January 1, 2011 to January 1, 2012, and from January 1, 2012 to July 1, 2013.
Industry insiders believe that the lag in oil quality and inadequate vehicle urea addition facilities are the main reasons for the delay in the implementation of standards. However, judging from international trends and domestic environmental demands, implementing the four national standards is imperative.
Industry insiders suggest that the first is to accelerate the pace of oil upgrading, otherwise, the implementation of the standard can only be on paper; the second is to establish and improve the urea supply system; the third is to implement a transition period for reasonable standards. The upgrading from State III to State IV is a serious challenge for heavy-duty vehicle companies. Not only is there a conversion cycle, but there must also be a certain inventory-digestion process for sales, and a year or so of transition and buffer period should be given. To adapt to new standards and new changes; Fourth, to strengthen the independent industrialization of key components research and development.