Q370R chemical composition Q370R mechanical properties Q370R zero cutting

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I. Introduction to Q370R: It is a domestic steel grade used for boilers and pressure vessels. The “Q” symbolizes yield strength, “370” denotes the yield value, and “R” refers to vessels. It is a grade that emerged after the release of the GB713-2008 standard. The old standard for Q370R was 15MnNbR; Q370R can be cut with zero waste (152+0375***0895). II. Method of indicating grades: For carbon steels and low-alloy high-strength steels, the grade is indicated by the yield strength value, along with the character \"Qu\" and the first letter of the pinyin for the character representing \"container\" in the case of pressure vessels. For example: Q370R. III. Dimensions, Shape, Weight and Allowable Deviations The dimensions, shape and allowable deviations of the steel plates shall comply with the provisions of GB/T 709--2006 ； At the request of the buyer, and through agreement between both parties, steel plates with stricter tolerance requirements can be supplied ； The steel plates are delivered based on their theoretical weight. The thickness used for this theoretical calculation is the arithmetic average of the maximum and minimum allowable thicknesses of the steel plates, with a density of 7.85 g/cm3 applied in the calculations. IV. Surface Quality: The surface of the steel plate must be free from any defects that could be harmful to its use, such as cracks, bubbles, scars, folds, and inclusions. There shall be no delamination on the side of the steel plate. V. Q370R steel plates are medium and low-temperature pressure steel plates that are widely used in industries such as petroleum, chemicals, power generation, and boilers. They are employed in the manufacture of equipment and components such as reactors, heat exchangers, separators, spherical tanks, oil and gas tanks, liquefied gas tanks, pressure vessels for nuclear reactors, boiler drum, liquefied petroleum gas cylinders, high-pressure water pipes in hydroelectric stations, and turbine casings. Produced domestically in Wugang. VI. The delivery condition for Q370R is normalized; the impact test is carried out at -20°C. It is also possible to follow the manufacturer’s or designer’s requirements. The standard for Q370R is GB713-2014. Delivery condition for Q370R: For Q370R steel plates used in containers, level 3 flaw detection is standard; however, upon special request, level 2 or level 1 flaw detection can be implemented. Other steel manufacturers do not provide level 3 flaw detection by default, and it must be specified if required.

VII. Chemical composition of Q370R: Chemical composition (mass percentage)/% for Q370R: C, Si, Mn, Cr, Ni, Mo, Nb, V, P, S, Al. Limits: ≤0.18, ≤0.55, 1.20–1.60, 0.015–0.050, ≤0.025, ≤0.015.

VIII. Mechanical properties of Q370R: Grade, delivery condition, plate thickness, tensile test, impact test, bending test. Values: Tensile strength, yield strength, elongation rate, temperature, V-notch impact energy at 180°B = 2a. Minimum values: 1873, 6064, 608. Minimum values at 1873°B: 1873, 6064, 608. For Q370R in normalized condition, at 20–20°C: d = 2a, d = 3a