Pressure Vessel Steel

Vessel plate is one of the many steel plates in a larger category, due to the boiler steel plate in the medium temperature (below 350 ° C) under high pressure, in addition to withstand high pressure, but also subject to impact, fatigue load and water and gas corrosion, the requirements to ensure a certain degree of strength, but also has good welding and cold bending properties.

Pressure vessel plate material has a very special composition and many excellent performance, this boiler steel is mainly used to make pressure vessels, for different situations, different uses, pressure vessel plate corresponding to the material that should be used to make is also different.

Manufacturing Process Of Vessel Steel Plate
The manufacturing process of pressure steel plate mainly includes smelting, continuous casting, rolling, heat treatment and other processes. In the smelting process, we should strictly control the quality and chemical composition of raw materials; in the continuous casting process, we should ensure the purity and temperature of the steel; in the rolling process, we should control the rolling temperature and deformation; in the heat treatment process, we should reasonably control the heating temperature and cooling rate to achieve the required mechanical properties and corrosion resistance.

Quality Control Of Pressure Plates
In order to ensure the quality and reliability of boiler quality plate, strict quality control is required during the production process. It is necessary to carry out quality inspection and control of raw materials; to carry out quality monitoring and recording of smelting, continuous casting, rolling and heat treatment processes; to carry out quality inspection and testing of finished products to ensure compliance with relevant standards and user requirements. At the same time, it is also necessary to strengthen the construction and operation of the quality management system to improve product quality and reliability.

Pressure vessel quality steel is widely used in petroleum, chemical and power station and boiler industries, using vessel plate to manufacture reactors, heat exchangers, separators, and ball tanks, oil and gas tanks, liquefied gas pins, and nuclear reactor pressure shells.

In addition, boiler quality plate is also used to manufacture boiler ladle as well as liquefied petroleum gas cylinders, high-pressure water pipe of hydroelectric power station, hydraulic turbine worm shell and other equipments or components, and pvq plate has a very broad market both at home and abroad.

Delivery State Of Pressure Vessel Steel

Steel plates for pressure vessel steel pressure elements shall be made of oxygen converter or electric furnace smelted sedentary steel. For low alloy steel plates and austenitic-ferritic stainless steel plates with the lower limit value of standard tensile strength greater than 540MPa, as well as for cryogenic steel plates with the design temperature lower than -20℃, the extra-furnace refining process should also be adopted.

Carbon steel and low alloy steel plate for welding, its C ≤ 0.25%, P ≤ 0.035%, S ≤ 0.035%.
The chemical compositions of carbon steel and low alloy steel plates in steel for pressure vessels are as follows:
(1) Steel with standard lower limit of tensile strength ≤540MPa, P≤0.030%, S≤0.020%;
(2) For steel with a lower value of standard tensile strength > 540 MPa, P ≤ 0.025%, S ≤ 0.015%;
(3) For steel with design temperature below -20℃ and lower limit value of standard tensile strength ≤540MPa, P≤0.025%, S≤0.012%;
(4) for the design temperature below -20 ℃ and the lower limit value of standard tensile strength > 540MPa steel, P ≤ 0.020%, S ≤ 0.010%.

Pressure Vessel Quality Steel Ultrasonic Testing

Thickness ≥ 12mm of carbon steel and low alloy steel plate (excluding multi-layer pressure vessel laminates) used in the manufacture of pressure vessels, the main pressure components, should be ultrasonic testing.