The development and main manufacturing method of spiral steel pipe

Spiral steel pipe in the proportion in recent years stabilized at 42% to 45%, the pipe on the rise. Spiral steel pipe and welded steel pipe is more variety of materials, reliability and adaptability, especially adapted to thick and steel production. The main problem is high investment, high cost, complex manufacturing process, wall thickness and ovality tolerances. The welded pipe is actually a plate of deep-processed products, the price of similar conditions, spiral steel pipe market competitiveness and improve its reliability, with the continuous improvement of the quality of steel plate and pipe technology and equipment level, part of the spiral steel occupy the market, there is the possibility of welded pipe replaced, but only very limited areas.

Spiral steel hot rolling process is the main manufacturing methods, accounting for 80% of heat production Seamless Pipe Mill production of varieties and quality levels in addition to mill their own skills, but to a large extent constrained by the smelting and casting Therefore advanced smelting process should refer to the complete process management process. International companies are mostly well-known spiral steel pipe factory, or a complete professional steel company, by outsourcing manufacturing spiral pipe billet is difficult for enterprises in the fierce competition in the market share steady position. Using an electric arc furnace smelting or refining a VD of LF handle a full vacuum casting casting tube round protection of a hot strip mill (NPN, PQF) a process, is the current international advanced sawl pipe production process, using the above process can produce such as OCTG, high-pressure boiler tubes, low-alloy tubes. Tianjin Pipe Corporation, Baosteel Trading (steel) company, Anshan Iron and Steel seamless factory, Baotou seamless factory are to achieve the above process, climbed into steel seamless and Hengyang Steel Tube Company is also supporting projects to build did not pay close attention to the recent realization of the above process can be process. For the smelting equipment, electric arc furnace or converter capacity of not less than 70 a lOOt, create conditions for the ladle refining, full attention should be rolling mill line inspection tools and automatic control system, equipped with advanced detection systems for positioning and high-pressure oil pipe boiler tube production line, should be equipped with a high level of heat treatment and processing systems, the progressive realization of billet hot charging of heat delivery and on-line often, controlled rolling and air cooling and other processes.