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.
All seamless q355b square tubes shall be tested for mechanical properties. Mechanical property tests are mainly divided into two categories: tensile test and hardness test.
Sao-Paulo.Viewing color: the color of the cold galvanized square tube is yellowish green, cyan white or slightly colored at a fixed angle with the sun. The color of hot-dip galvanized square pipe is silver white at a fixed angle with the sun.
Surface adhesion resistance is an important feature of square tubes. At present, square tubes are mostly used for transportation, so the adhesion resistance makes square tubes not stick during transportation.
.Performance index analysis of square tube - plasticity refers to the ability of metal materials to produce plastic deformation without deformation under load.
The square tube is a low-alloy high-strength structural steel with carbon content of 0.1% - 0.25%, and the main alloy elements manganese, silicon, vanadium, niobium and titanium are added; Its total alloy content is 3%. According to the strength, it is divided into four levels: 300, 350, 400 and 450MPa.
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.
Hot rolled q355b square tube continuous casting slab or blooming slab is used as raw material, heated by stepping heating furnace and descaled by high-pressure water into roughing mill. Roughing material enters finishing mill after head cutting, tail cutting and then computer rolling. After final rolling, it is rolled into straight hair coil through laminar cooling and coiler. The head and tail of straight hair curl are often tongue shaped and fish tail shaped, with poor accuracy of thickness and width, and there are often defects such as wave shape, hem, tower shape and so on. The coil weight is heavy and the inner diameter of the steel coil is 690mm.
Cold drawn or cold rolled precision square tube (gb3639-200) is a cold drawn or cold rolled precision square tube with high dimensional accuracy and good surface finish for mechanical structure and hydraulic equipment. The selection of precision square mechanical structure or hydraulic equipment can greatly save machining hours, improve material rate and improve product quality.
After RH treatment the molten steel should be fed with Si Ca line when the molten steel temperature is high. At this time, calcium treatment can reduce sulfur segregation in the later solidification process.
Affordable price.Square tube has good machinability, good cold deformation plasticity and weldability; In addition, but it has quite high strength and wear resistance, this steel has great resistance to white spots temper brittleness and overheating during heat treatment.
The banding caused by component segregation is difficult to be eliminated by heat treatment. Generally, normalizing can correct the segregation to the allowable level. If the banding is serious normalizing can reduce this segregation to a certain extent. Generally, it can be improved by multiple normalizing. It is reliable to conduct high-temperature diffusion annealing first and then normalize again, but the cost will be very high, which is difficult to achieve for the steel plate due to the surface quality.
From the perspective of production, we should give full play to the productivity of production equipment and reduce the consumption of fuel and equipment on the basis of meeting the size and performance requirements of q355b square tube. Therefore, the temperature of no open forging and final forging is a comprehensive technical and economic problem. If qualified q355b square tubes can be obtained in the temperature range of the vehicle, reasonable process procedures should be selected from an economic point of view. Obviously, the higher the temperature, the easier the forging and the higher the productivity, but the greater the fuel consumption and the loss of the heating furnace; We should consider these two aspects and make a reasonable choice.
It is feasible to use the theory to calculate static structures, such as warehouses, but it is not suitable for moving components such as wheels. At this time, people often use the plastic theory. The research of the plastic theory can be traced back to 1914. In 1975, the European Design Association formulated a plastic design code, which is mainly used for static load plane beams and frame structures subjected to bending stress The solution is as follows: for high-rise buildings, more detailed calculations are needed.
Create brilliance.In different environments, the use efficiency of square tubes is different. According to the quality of square tubes, we will conduct progressive research on them, hoping to develop better square tubes. No matter what environment, we will make square tubes suitable for use. Then, what is the role of shot blasting and sand blasting in each other's pipe? Next, let's introduce it to you.
Put the pig iron for steelmaking into the steelmaking furnace according to the specified process to obtain steel. The products of steel include ingots, continuous casting billets and various steel castings made of straight square tubes. Generally speaking, steel refers to the steel rolled into various square tubes. Square tube steel belongs to ferrous metal, but steel is not completely equal to ferrous metal.
Square pipe is an important pipe. Its application in various fields has different performance. According to its different performance, we have carried out different transformation on the other pipe to ensure that the square pipe can be better used. We should make the right choice when purchasing. Below I will introduce the correct way of painting the lower pipe.
Sao-Paulo.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.
The square tube can be sprayed with fluorocarbon paint, which needs some treatment before spraying.
The square tube is a low-alloy high-strength structural steel with carbon content of 0.1% - 0.25%, and the main alloy elements manganese, silicon, vanadium, niobium and titanium are added; Its total alloy content is 3%. According to the strength, it is divided into four levels: 300, 350 400 and 450MPa.