A 2.8 ton drop hammer, falling from a height of 3 meters, instantly generates 80,000 joules of energy and can easily break a 5-centimeter thick steel plate.
This kind of impact resistance experiment was conducted at ZJGG Steel Pipe Technology Corporation, and the experimental object was a world leading 3,500 meter ultra deep underwater pipeline welded steel pipe.
Deep sea pipes need to adapt to working environments with lower temperatures, higher pressures, and stronger corrosion. Especially in the deep sea at a depth of 3,500 meters, there are extremely low temperatures close to 0 ℃ and ultra-high pressures equivalent to about 350 times the standard atmospheric pressure. Therefore, there are very strict requirements for the strength and toughness, compressive performance, dimensional accuracy, and other indicators of deep-sea pipes.
The “Development and Industrialization of 3500 meter Ultra Deep Water High Pressure Submarine Pipeline” project led by ZJGG is aimed at the special needs of ultra deep water high pressure submarine pipeline engineering. Through research on steel pipe forming technology, welding technology, and inspection technology, key technical problems such as deep sea pipeline steel smelting, rolling, and plate forming and welding have been solved.
Strength and toughness are a pair of contradictions, and maintaining high index values of both strength and toughness is one of the biggest technical difficulties in research and development. To solve this contradiction, ZJGG adopts the principle of multiphase microstructure alloying and control, achieving a good match between high strength, toughness, high plasticity, and fatigue resistance of materials, thereby enabling deep-sea steel pipes to achieve both rigidity and toughness.
In addition to breakthroughs in material technology, the manufacturing technology of ZJGG longitudinal submerged arc welded steel pipes has achieved important technological innovations in material forming, welding, corrosion prevention, and physical and chemical performance testing. A sample of welded steel pipes for 3500 meter ultra deep underwater pipelines has been successfully produced, which can meet engineering and technical requirements such as compressive collapse, fatigue resistance, and large deformation resistance.
At present, the underwater application of welded steel pipes for deep-sea oil and gas transportation in China is limited to 1500 meters, and the depth of 3500 meters is a blank field.
The 3500 meter ultra deep underwater pipeline welded steel pipe sample developed by ZJGG not only fills the technological gap in this field in China, but also marks the first time this research has been conducted worldwide, with technology at a leading level globally.
At present, this product is applied in submarine oil and gas pipeline projects such as the “Enping” and “Yacheng” gas fields in the South China Sea and Nigeria, achieving industrial development of research results while breaking through core key technologies.
With the successful development and manufacturing of a 3500 meter ultra deep underwater pipeline, ZJGG has accumulated technical expertise and a good reputation for performance. It has also won the world’s longest heated crude oil pipeline order, with a total amount of approximately 2.5 billion yuan, providing a total of 260000 tons of straight seam submerged arc steel pipes for the 1500 kilometer long energy “artery” in East Africa.
The company’s products are exported to over 80 countries in Asia, Africa, Europe, South America…