The characteristic of niobium in A514 Gr E quenched and tempered steel etc. steel material is to increase the recrystallization temperature of austenite, so as to achieve the purpose of refining austenite grains. In general, the amount of niobium added in steel material is less than 0.05%, and the contribution of niobium above 0.05% to strengthening and toughening will no longer be obvious.
Q345DR steel is a pressure vessel special plate with yield strength of 340MPa grade. It has good comprehensive mechanical properties and process performance. Phosphorus, sulfur content than ordinary 16Mn steel, in addition to tensile strength, elongation requirements than ordinary 16Mn steel has been improved, but also required to ensure impact toughness. A514 Gr E quenched and tempered steel was China's most widely used, the largest amount of pressure vessel special steel.
In February, the European steel price index was 161.2 points, up 1.3 points on a month on month basis, up 0.8%; the euro zone manufacturing PMI was 49.2%, up 1.3 percentage points on a month on month basis. The manufacturing PMI of Germany, Italy, France and Spain were 48%, 48.7%, 49.8% and 50.4% respectively. This month, among the main steel products such as A514 Gr E quenched and tempered steel in the German market, the price of wire rod decreased slightly, the price of section steel remained stable, and other products continued to rise.
The outer diameter of the hot-rolled seamless pipe is generally larger than 32mm, and the wall thickness is 2.5-75mm. The diameter of the cold-rolled seamless pipe can be 6mm, the wall thickness can be 0.25mm, the outer diameter of the thin-walled pipe can be 5mm, and the wall thickness is less than 0.25mm. The size accuracy of the cold-rolled seamless pipe is higher than that of the hot-rolled seamless pipe, A514 Gr E quenched and tempered steel.
