MstsislawPrice of DN100 galvanized pipeThe market trading atmosphere is insufficient, and the quotation is stable and declining

The general delivery length of q355b square pipe is 4000mm-12000mm mostly 6000mm and 12000mm. Q355b square tube is allowed to deliver short and non fixed length products not less than 2000mm, or in the form of interface tube, but the Demander shall cut off the interface tube when using it. The weight of short length and non fixed length products shall not exceed 5% of the total delivery. For q355b square tube with theoretical weight greater than 20kgm, seamless square tube and square tube.

Today cold drawn seamless square tube, with the development of the world, all fields are coming rapidly, which makes the demand for square tube higher and higher, and the requirements of customers for square tube higher and higher. Now we are studying a new square tube. The following mainly introduces the performance of square tube in tensile strength.

Mstsislaw.There are many processing technologies for square tubes. I won't introduce the specific processing technology here. We only know about the processing technology of each other's tubes. We may have insufficient understanding of its heating technology. Next, I'll give you a detailed introduction to the heating technology of the lower tubes.

The strength, plasticity and angle discussed later are the machine function indicators of metal under static load. In practice, many mechanical machines are under repeated load, and the whole opportunity is tired in this environment.

.Functional index analysis of square tube - commonly used are square tube Brinell angle (HB), Rockwell angle (HRC) and Vickers angle (HV). Angle is a gauge needle to weigh the soft and hard level of metal data. The angle method is rarely used to determine the internal angle in the current life. It uses the metal data surface tested under the fixed load of the indenter with a certain number and shape to determine its angle value according to the level of the object.

The square tube represents the large capacity of the metal material under the action of tension, and the calculation formula is: where: FB -- the strong force borne by the sample when it is broken, n (Newton); So -- original cross-sectional area of sample, mm2. Yield point (& sigma; s) the stress of metal material with yield phenomenon when the specimen can continue to elongate without increasing (keeping constant) the force during the tensile process, which is called the yield point.

The belt is sent to the metal flaw detector (or hydrostatic test) for internal flaw detection. If there are cracks, bubbles and other problems inside the steel pipe, they will be detected. Steel pipes should be strictly selected manually after quality inspection. After the steel pipe is inspected, the number, specification, production batch number, etc. shall be sprayed with paint. And hoisted into the warehouse by crane.

In the standard of q355b square tube, most of them specify tensile test and hardness test at the same time. For those materials that are not convenient for hardness test, such as q355b square tube, only tensile test is specified. In particular, the new portable surface Rockwell hardness tester and pipe Rockwell hardness tester can quickly and accurately test the hardness of stainless steel plate, stainless steel strip and q355b square tube as thin as 0.05mm, which makes it easy to solve the problems that were difficult to solve in China in the past.

Square tube, modified square tube, square tube, Q345B square tube and hot-rolled square tube are qualified in quality inspection. The manufacturer adopts advanced equipment to ensure the quality of each product. Magnetic flux leakage testing for surface defects of square tubes is very similar to magnetic particle testing for square tubes, sensitivity and reliability are stronger than magnetic particle testing. Indirect square forming process the traditional forming process of cold-formed square pipe is to gradually roll the hot-rolled steel coil multi stand forming unit into round pipe at room temperature, and then the shaping unit will roll the round pipe into square pipe, which is suitable for rolling small and medium-sized products. Rolling with this process & ldquo; Superb & rdquo; Square tube will show its inherent defects. Because the roll work in the bending process of this process is always concentrated at the point, excessive stress concentration often shows microcracks in the bending process of profiles, which will lead to cracking in serious cases. The products with such defects have serious consequences when they are used in building steel structures. The study of the broken square tube column in the Hanshin earthquake in Japan shows that the corner microcrack is the main cause of the square tube fracture. At the same time, due to the different forming bending radians of products with different wall thickness, the universality of rolls is limited. The large-size cold-formed square tube used in the process adopts the advanced & ldquo; Direct Square & rdquo; The production process is to directly roll the hot-rolled steel coil into a square and rectangular shape at room temperature.

In terms of hot working, repeated upsetting and multi-directional rolling of ingot can not only reduce the level of carbide segregation in square tube, but also improve the anisotropy of steel.

Product range.The advantages of real bending are small reverse, accurate forming, and as long as the roll shape is accurate, the R of inner corner forming is more accurate.

One of the steps that are prone to defects in the production of square tubes is heat treatment and the other is tensile treatment. Today we need to know the latter. Maybe some people will have a lot of questions about why square tubes are prone to defects in tensile. Now let's analyze the specific causes of defects.

At present, researchers at home and abroad have carried out experimental discussion on the anti adhesion of square tube surface. So far there is still a lack of research on surface adhesion, and there is a lack of operable and low-cost inner surface preparation technology of square pipe. In terms of solid surface adhesion mechanism, based on the solid-liquid interface adhesion work theory and smooth solid surface model, this paper analyzes the spreading process on machined rough surface, studies the dynamic movement characteristics of solid-liquid vapor phase line, directly analyzes the adhesion process, and establishes a line spreading model based on small system energy, It provides theoretical guidance for the preparation of anti adhesion surface of pipeline.

Job description.Now, with the continuous development of q355b square tube, its use is becoming more and more extensive, and the technology is also following up. Therefore,MstsislawHot rolled seamless square tube, we still look forward to the development of q355b square tube in the future.

Among them, q355b square tube is divided into: (a) by process & mdash& mdash; Arc welded square pipe, resistance welded square pipe (high frequency and low frequency), gas welded square pipe and furnace welded square pipe (b) are divided by weld & mdash& mdash; Straight welded square pipe

Cutting: 1 to be fast, no teeth, or whether the cutting line is flat, the starch taste of oil affects the quality of dishes. First choose to cut potatoes with less sharp bottom, so when you cut, it's easy to leave the corner of the side end.

Mstsislaw.The normal process flow is as follows: the round steel is perforated to form a tube embryo, then pickling is carried out, the black skin on the outer surface is washed off, and then grinding is carried out. After passing the inspection, the rolling mill or cold drawing and cold drawing are carried out. Annealing is required for wall reduction, but not for air drawing. After forming, annealing and straightening are carried out, and pickling is tested and stored in the warehouse. Basically, these are the processes. Better manufacturers will perform whitening treatment during annealing to make the surface treatment more beautiful. The narrow blank of square pipe can produce welded pipe with larger diameter and the blank of the same width can also produce welded pipe with different diameter. However, compared with the straight seam square pipe with the same length, the weld length increases by 60%, and the production speed is low. Square pipes with large or thick diameter are usually made of steel blank directly, while small welded pipes and thin-walled welded pipes only need to be directly welded with steel strip. Then after simple polishing,MstsislawBright square tube, wire drawing is OK. Therefore straight seam welding is mostly used for relatively welded pipes, and spiral welding is mostly used for large-diameter welded pipes.

Hardness test is to determine the hardness of seamless q355b square pipe by slowly pressing a hard indenter on the sample surface according to the specified conditions, and then testing the indentation depth or size.

Degrease.