Thermal expansion pipe is divided into seamless steel pipe and hot expanded seamless pipe, ERW high frequency by the former straight seam welded steel pipe hot expanding processing, the weld heat treatment at intermediate frequency weld produce certain changes gradually fades almost invisible by ultrasonic, hydrostatic testing to determine whether the weld cracks, and both ends of the nozzle is cracking, after passing through the check weld surface without signs of damage, and then spray standard factory, professional for this hot rolling pipe sewage, water, transportation and other low-pressure fluid pipe, and hot expanding seamless steel pipe is extended out of the limited size larger diameter and a special caliber thermal expansion, product specification is not only the full complement of seamless pipe was incomplete, but also in the caliber aspect is to meet the domestic demand for large-diameter pipe, but the pressure and the physical and chemical properties than the original slightly vary. introduced advanced IF push the system unit, the hot expanding of technology has fully met the requirements of national standard GB, the production of hot rolling pipe can be used in low-pressure pipe, thick-walled hot rolling pipe now available in the boiler, chemical, power plants and other high-pressure pipeline, product qualification rate of 100%.
Thermal expansion is a steel processing methods, which is the small diameter pipe into large diameter steel tube processing. Thermal expansion pipe somewhat less than some of the mechanical properties of hot-rolled steel. Limited to steel pipe specifications is limited, according to the needs of the end consumer hot rolling pipe so it was born, hot rolling tube specifications randomness is relatively large, generally based on the needs of customers and the production of thermal expansion of steel is what we often say the hot rolling, the density is relatively low, but a strong contraction pipe, ( seamless steel pipe ) can be referred to as thermal expansion.
Thermal expansion pipe using two -step expansion of the machine set -propelled flaring cone mold technology, digital intermediate frequency induction heating technology, hydraulic technology in one machine, with its rational process, lower energy consumption, lower capital investment, a good product quality, a wide range of raw materials and product specifications applicability, flexible variable low-input production batch adaptability, replace the steel industry pull aside the traditional style expanding technology. Difficult to resolve because the supply of large-diameter steel tube, thermal expansion pipe became solve the shortage of large-diameter pipe source of important products to ease the supply of large diameter steel tube market tensions.
