Tensile strength: 490-675 yield strength: & Ge; 345 elongation: & Ge; 22 mechanical properties of seamless pipe: tensile strength: 490-675 yield strength: ≥ 345 elongation: & Ge; 21 mechanical properties of seamless pipe: tensile strength: 490-675 yield strength: ≥ 345 elongation: & Ge; 21 mechanical properties of seamless pipe: tensile strength: 490-675 yield strength: ≥ 345 elongation: & Ge; 22 mechanical properties of seamless pipe: tensile strength: 490-675 yield strength: ≥ 345 elongation: & Ge; 22 square tube belongs to low alloy series. It is one of the materials of seamless steel pipe. In low alloy materials, this material is ordinary. Square tube used to be called Q345B square tube.
Mechanical properties of seamless q355b square tube: tensile strength & sigma; b (MPa)：≥ 980 yield strength & sigma; s (MPa)：≥ 835 elongation & Delta; 5(%)：≥ 12 reduction of area & psi; (%)：≥ 40 impact absorption energy (impact value) (aku2j): & Ge; 39 the products produced by the more complex technology are exquisite. At present, Fangguan is highly praised by the public in the market. What is important is that there is a good guarantee in terms of quality. Therefore whether Fangguan can obtain such a high market evaluation depends on the complex technology of Fangguan.
Jersey-City.For transportation: water supply, sewage treatment engineering drainage, mud transportation, marine water transportation.
The tensile test is to make q355b into a sample, pull the sample to fracture on the tensile testing machine, and then measure one or more mechanical properties. Usually, only tensile strength, yield strength, elongation after fracture and reduction of area are measured. Tensile test is the basic mechanical property test of metal materials. Almost all metal materials have specified tensile test as long as they have requirements for mechanical properties. Especially for those materials whose shape is not convenient for hardness test, tensile test has become the only means to test mechanical properties.
.First, remove the deposits on the surface of the square pipe surface with copper wire brush. Use the perfume oil or other scrubbing oil on the surface layer, or use phosphate or chromate solution, brush, spray or dip coating. After the fixed reaction time, rinse the acid solution with plenty of fresh water on the surface.
Mechanical polishing: after processing, the parts have good levelness, short gloss, dull and rusty. Suitable for processing simple parts, medium and small products.
Square pipe is a square steel pipe cold drawn from seamless steel pipe, which is not a straight q355b square pipe, and q355b square pipe, also known as welded pipe, is a square pipe welded by steel plate or strip steel after crimping. Q355b square tube has the advantages of simple production process, high production efficiency, many varieties and specifications and less equipment. The commonly used materials are Q235A and Q235C.
After chemical treatment and surface treatment of the square tube, the appearance and quality of the square tube have been improved to another height, making the current square tube present in the market in a good state.
According to smelting classification and furnace type, A. open hearth steel: (a) acid open hearth steel; (b) Alkaline open hearth steel.
The q355b square tube rolled from the strip steel through process treatment is generally to unpack, flatten, curl and weld the strip steel to form a round tube, then roll the round tube into a square tube, and then cut it to the required length. Nowadays the forming of q355b square tube has solid bending and empty bending. The bending degree of q355b square tube shall not be greater than 3mm per meter, and the total bending degree shall not be greater than the actual bending of the total length. As the name suggests, the bending is compacted, and the internal and external rollers and the internal and external walls of the tube blank are compacted in both directions during the actual bending.
Range.Square tube flattening test is a kind of test to check the deformation performance of metal tubes (seamless square tubes and rectangular tubes) flattened to the specified size and show their defects. Relevant flattening tests shall be carried out in accordance with relevant provisions of test standards. Requirements for samples samples can be taken from metal pipes with qualified appearance. Generally, sawing is adopted. The inner and outer walls of the pipe shall retain the original surface without any processing. Sample length L & asymp; D (D is the outer diameter of the pipe). When the outer diameter is large, the length l shall not exceed 100mm. When the outer diameter is less than 20mm, l = 20mm. When cutting the sample, the surface of the sample shall not be damaged and the performance of the metal shall not be changed due to heating or cold processing. The edge of the section shall be flattened. The flattening test is a test to check the deformation performance of the metal pipe (seamless square pipe and rectangular pipe) flattened to the specified size and show its defects. Relevant flattening tests shall be carried out in accordance with relevant provisions of test standards.
High temperature diffusion heat treatment of ingot can improve the composition heterogeneity of ingot and improve the transverse performance of square tube.
After perforation, continuous rolling or rolling. Take off the pipe after sizing. The conical drill bit of the sizing machine rotates into the steel embryo at high speed to form a steel pipe. The inner diameter of the steel pipe is determined by the outer diameter length of the sizing machine bit. After sizing, the steel pipe enters the cooling tower for water spray cooling. After cooling the steel pipe will be straightened. After straightening the steel pipe
The strip caused by component segregation, when the steel contains harmful impurities such as phosphorus and is pressed and delayed, the impurities elongate along the rolling direction. When the steel is cooled below 4, these impurities become the core of ferrite, and then pearlite distributed in bands. This band can be eliminated by electroslag remelting and increasing crystallization speed.
original.The surface compressive stress characteristics of the square tube will be obtained after isothermal quenching.
Empty bending empty bending is the bending moment formed in one direction between the outer roll and the outer wall of the tube blank to bend the strip. Empty bending will compress the bending line, the compression effect will lengthen the bending line longitudinally, and the metal at the bending will accumulate and thicken, which is the compression thickening effect of empty bending.
Brinell hardness, Rockwell hardness and Vickers hardness are commonly used.
Jersey-City.Banded due to improper hot working temperature, that is, when the hot working stop forging temperature is in the phase zone (between, and 40), and the undigested austenite is cut into bands. When it is cooled to a, the banded austenite is transformed into banded pearlite. This can be improved or eliminated by increasing the final rolling temperature, increasing the forging ratio, diffusion annealing and normalizing.
Spray fluorocarbon paint after.
In & sigma; Expressed in%. The calculation formula is: where: L1 -- gauge length after sample breaking, mm; L0 -- original gauge length of sample, mm. Reduction of area (& psi;) in the tensile test, the percentage between the large reduction of the cross-sectional area at the reduced diameter and the original cross-sectional area after the specimen is broken is called the reduction of area. In & psi; Expressed in%. The calculation formula is as follows: where: S0 -- original cross-sectional area of the sample, mm2; S1 -- small cross-sectional area at the reduced diameter after sample breaking, mm2.