What factory can use steel structure?

It is used in many places, and there are dry steel structures in general. They are used in factory buildings and general factories, including roadside welding workshops. According to the different uses of steel, the first thing you need to add is the knowledge of steel. Then go to customers according to different uses. That would be easy. Let me tell you some basic knowledge about steel: steel knowledge: practical knowledge about pipelines.

I. Pipeline classification 1. Seamless pipes are classified according to production methods (1)-heat pipes, cold-rolled pipes, cold-drawn pipes, extruded pipes and pipe jacking (2)-welded pipes (a) are classified according to processes-arc welded pipes, resistance welded pipes (high frequency and low frequency), gas welded pipes and furnace welded pipes (b) are classified according to welds. Oval steel pipes, triangular steel pipes, hexagonal steel pipes, rhombic steel pipes, octagonal steel pipes, semicircular steel rings, other (2) steel pipes with complex sections-equilateral hexagonal steel pipes, five-petal plum-blossom steel pipes, biconvex steel pipes, biconcave steel pipes, melon-seed-shaped steel pipes, conical steel pipes, corrugated steel pipes, watchcase steel pipes, others 3. Classification by wall thickness-thin-walled steel pipe, thick-walled steel pipe and its application. Steel pipes for machinery industry, petroleum, geological drilling, container, chemical industry and special purpose. 2. Seamless steel pipe refers to a long steel pipe with a hollow section and no seams around it. Steel pipe has a hollow cross section and is widely used as a pipeline for conveying fluids (such as oil, natural gas, gas, water and some solid materials). Compared with solid steel such as round steel, steel pipe is lighter in weight under the same bending and torsion strength, and it is an economic section steel, which is widely used to manufacture structural parts and mechanical parts, such as oil drill pipes, automobile transmission shafts, bicycle racks, steel scaffolding for construction, etc. Manufacturing annular parts with steel pipes can improve the utilization rate of materials, simplify the manufacturing process and save materials and processing time, such as rolling bearing rings and top sleeves. At present, steel pipes have been widely used to make them. Steel pipe is also an indispensable material for all kinds of conventional weapons, and the barrel and barrel are made of steel pipe. According to the different cross-sectional shapes, steel pipes can be divided into round pipes and special-shaped pipes. Because the circular area is the largest when the circumference is equal, the circular tube can transport more fluid. In addition, when the circular section bears internal or external radial pressure, the force is relatively uniform, so steel pipes are mostly round pipes. However, circular tubes also have some limitations. For example, in the case of plane bending, the bending strength of circular tubes is not as high as that of square tubes and rectangular tubes, which are commonly used in some agricultural machinery skeletons and steel and wood furniture. According to different uses, special-shaped steel pipes with other cross-sectional shapes are needed.

1. Seamless Steel Pipe for Structure (GB/T8 162- 1999) is a seamless steel pipe for general structure and mechanical structure.

2. Seamless Steel Pipe for Fluid Transportation (GB/T8 163- 1999) is a common seamless steel pipe for conveying fluids such as water, oil and gas.

3. Seamless Steel Pipe for Medium and Low Pressure Boilers (GB3087- 1999) is a kind of high-quality carbon structural steel hot-rolled and cold-drawn (rolled) seamless steel pipe for manufacturing superheated steam pipes, boiling water pipes and superheated steam pipes of locomotive boilers with various structures. 4. Seamless Steel Pipe for High-pressure Boiler (GB53 10- 1995) is a kind of high-quality carbon steel, alloy steel and stainless heat-resistant steel seamless steel pipe used to manufacture the heating surface of high-pressure and above water-tube boilers. 5. The high-pressure seamless steel pipe for fertilizer equipment (GB6479-86) is a kind of high-quality carbon structural steel and alloy steel seamless steel pipe suitable for chemical equipment and pipelines with working temperature of -40~400℃ and working pressure of 10~30Ma. 6. Seamless Steel Pipe for Petroleum Cracking (GB9948-88) is a kind of seamless steel pipe suitable for refinery tubes, heat exchangers and pipelines. 7. The steel pipe for geological drilling (YB235-70) is the steel pipe used for core drilling by the geological department, which can be divided into drill pipe, drill collar, core pipe, casing pipe and settling pipe according to the purpose. 8. Seamless Steel Pipe for Diamond Core Drilling (GB3423-82) is a seamless steel pipe for drill pipe, mandrel and casing for diamond core drilling. 9. Oil drilling pipe (YB528-65) is a kind of seamless steel pipe with both ends thickened internally or externally, which is used for oil drilling. There are two kinds of steel pipes: turning wire and non-turning wire. The turning wire is connected with the joint, and the non-turning wire is connected with the tool joint by butt welding. 10. Marine Carbon Steel Seamless Steel Pipe (GB52 13-85) is a kind of carbon steel seamless steel pipe used for manufacturing primary pressure-resistant piping system, secondary pressure-resistant piping system, boilers and marine superheaters. The working temperature of carbon steel seamless steel pipe wall shall not exceed 450℃, and the working temperature of alloy steel seamless steel pipe wall shall not exceed 450℃. 1 1. Seamless Steel Pipe for Automobile Bushing (GB3088-82) is a high-quality carbon structural steel and alloy structural steel hot-rolled seamless steel pipe for manufacturing automobile bushings and axle housings. 12. Diesel Engine High Pressure Tubing (GB3093-86) is a cold-drawn seamless steel pipe for manufacturing diesel engine injection system high pressure tubing. 13. The precision inner diameter seamless steel pipe (GB87 13-88) for hydraulic cylinder and pneumatic cylinder is a kind of precision cold-drawn or cold-rolled seamless steel pipe with precision inner diameter. 14. Cold-drawn or cold-rolled precision seamless steel pipe (GB3639-83) is a precision cold-drawn or cold-rolled seamless steel pipe with high dimensional accuracy and good surface finish for mechanical structures and hydraulic equipment. Using precision seamless steel tube to manufacture mechanical structure or hydraulic equipment can greatly save processing time, improve material utilization and improve product quality. 15. Seamless Stainless Steel Pipe for Structure (GB/T 14975- 1994) is a hot-rolled (extruded, expanded) and cold-drawn (rolled) seamless steel pipe made of stainless steel, which is widely used in chemical industry, petroleum, textile, medical treatment, food, machinery and other industries.

16. Seamless Stainless Steel Pipe for Fluid Transportation (GB/T 14976- 1994) Hot rolled (extruded, expanded) and cold drawn (rolled) seamless steel pipes made of stainless steel for fluid transportation. 17. Special-shaped seamless steel pipe is the general name of seamless steel pipe with other cross-sectional shapes except circular pipe. According to the different cross-sectional shapes and sizes of steel pipes, they can be divided into special-shaped seamless steel pipes with equal wall thickness (code D), special-shaped seamless steel pipes with unequal wall thickness (code BD) and special-shaped seamless steel pipes with variable diameter (code BJ). Special-shaped seamless steel pipes are widely used in various structural parts, tools and mechanical parts. Compared with circular tubes, special-shaped tubes generally have larger moment of inertia and section modulus, and have greater bending and torsion resistance, which can greatly reduce structural weight and save steel. Third, welded steel pipes Welded steel pipes, also known as welded pipes, are steel pipes made of steel plates or steel belts after pressure welding. Welded steel pipe has simple production process, high production efficiency, many varieties and specifications and few equipment, but its strength is generally lower than that of seamless steel pipe. Since 1930s, with the rapid development of high-quality strip continuous rolling production and the progress of welding and inspection technology, the weld quality has been continuously improved, and the varieties and specifications of welded steel pipes have been continuously increased, replacing seamless steel pipes in more and more fields. Welded steel pipes are divided into straight welded pipes and spiral welded pipes according to the weld forms. The production process of straight welded pipe is simple, with high production efficiency, low cost and rapid development. The strength of spiral welded pipe is generally higher than that of straight welded pipe. Welded pipes with larger diameters can be produced from narrow blanks, and welded pipes with different diameters can also be produced from blanks with the same width. However, compared with the straight seam pipe with the same length, the weld length increases by 30~ 100%, and the production speed is lower. Therefore, straight seam welding is mostly used for welded pipes with smaller diameter, and spiral welding is mostly used for welded pipes with larger diameter.

1. Welded steel pipe (GB/T3092- 1993) used for low-pressure fluid transportation is also called general welded pipe, commonly known as black pipe. It is a welded steel pipe, which is used for conveying water, gas, air, oil, heating steam and other general low-pressure fluids. The wall thickness of steel pipe is divided into ordinary steel pipe and thickened steel pipe; The nozzle end can be divided into two types: unthreaded pipe (smooth pipe) and threaded pipe. The specifications of steel pipes are expressed in nominal diameter (mm), which is an approximation of the inner diameter. Traditionally expressed in inches, such as 1 1/2, etc. The welded steel pipe for low-pressure fluid transportation is not only directly used for fluid transportation, but also used as the original pipe of galvanized welded steel pipe for low-pressure fluid transportation. 2. Galvanized welded steel pipe (GB/T309 1- 1993) for low-pressure fluid transportation is also called galvanized welded steel pipe, commonly known as white pipe. It is a hot-dip galvanized welded (furnace welding or electric welding) steel pipe, which is used for conveying water, gas, gas oil, heating steam, warm water and other general low-pressure fluids or other purposes. The wall thickness of steel pipe is divided into ordinary galvanized steel pipe and thickened galvanized steel pipe; The nozzle end is divided into unthreaded galvanized steel pipe and threaded galvanized steel pipe. The specifications of steel pipes are expressed in nominal diameter (mm), which is an approximation of the inner diameter. Traditionally expressed in inches, such as 1 1/2, etc. 3. Ordinary carbon steel wire sleeve (GB3640-88) is a steel pipe used to protect wires in industrial and civil buildings, mechanical equipment installation and other electrical installation projects. 4. The longitudinal welded steel pipe (YB242-63) is a steel pipe whose weld is parallel to the longitudinal direction of the steel pipe. Usually divided into metric welded steel pipes, welded thin-walled pipes, transformer cooling oil pipes, etc. 5. Spiral seam submerged arc welded steel pipe (SY5036-83) for pressure fluid transportation is a spiral seam steel pipe made of hot-rolled steel strip coil as tube blank, which is spirally formed at room temperature and welded by double-sided submerged arc welding. Steel pipe has strong bearing capacity and good welding performance, and it is safe and reliable to use after various rigorous scientific inspections and tests. The steel pipe has large diameter and high conveying efficiency, which can save the investment in laying pipelines. Mainly used for transporting oil and natural gas pipelines. 6. Spiral seam high-frequency welded steel pipe for pressure fluid transportation (SY5038-83) is a kind of spiral seam high-frequency welded steel pipe for pressure fluid transportation, which is formed by spiral forming at room temperature and high-frequency lap welding. Steel pipe has strong bearing capacity and good plasticity, which is convenient for welding. After various rigorous scientific inspections and tests, it is safe and reliable to use, with large steel pipe diameter and high conveying efficiency, which can save the investment in laying pipelines. Mainly used for laying pipelines for transporting oil, natural gas, etc. 7. Spiral seam submerged arc welded steel pipe (SY5037-83) for general low-pressure fluid transportation is a submerged arc welded steel pipe with hot-rolled steel coil as tube blank, which is spirally formed at room temperature by double-sided automatic submerged arc welding or single-sided welding, and is used for general low-pressure fluid transportation such as water, gas, air and steam. 8. The spiral seam high-frequency welded steel pipe (SY5039-83) for general low-pressure fluid transportation is made of hot-rolled steel strip coil, which is spirally formed at room temperature and welded by high-frequency lap welding. 9. Spiral welded steel pipe for pile (SY5040-83) is made of hot-rolled steel strip coil, which is spirally formed at room temperature and welded by double-sided submerged arc welding or high frequency welding. Steel pipes used as foundation piles for civil building structures, docks, bridges, etc. 4. Steel-plastic composite pipe and large-diameter coated steel pipe are based on hot-dip galvanized steel pipe, and plastic is coated on the inner wall (or outer wall if necessary) by powder melt spraying technology, which has excellent performance. Compared with galvanized pipe, it has the advantages of corrosion resistance, no rust, no scaling, smooth, clean, non-toxic and long service life. According to the test, the service life of steel-plastic composite pipe is more than three times that of galvanized pipe. Compared with plastic pipes, it has the advantages of high mechanical strength, good pressure resistance and heat resistance. Because the matrix is steel pipe, there is no problem of embrittlement and aging. It can be widely used in fluid transportation and heating projects such as tap water, gas and chemical products, and is an upgraded product of galvanized pipes. Because its installation and use methods are basically the same as traditional galvanized pipes, and the fittings are exactly the same, and it can replace aluminum-plastic composite pipes to play a role in large-diameter tap water transportation, it is well received by users and has become one of the most competitive new products in the pipeline market. The coated steel pipe is formed by plastic coating on the basis of large-diameter spiral welded pipe and high-frequency welded pipe, and the maximum nozzle diameter is 1200mm. Plastic coatings with different properties such as polyvinyl chloride (PVC), polyethylene (PE) and epoxy resin (EPOZY) can be coated according to different needs, and it has the characteristics of good adhesion, strong corrosion resistance, chemical corrosion resistance such as strong acid and alkali, non-toxic, non-corrosive and wear-resistant. There is no solvent or exudation substance in the coating, which will not pollute the conveying medium and ensure the purity and hygiene of the fluid. It can be used alternately in the range of -40℃ to +80℃ without aging and cracking, so it can be used in harsh environments such as cold areas. Large-diameter coated steel pipe is widely used in tap water, natural gas, petroleum, chemical industry, medicine, communication, electric power, ocean and other engineering fields.

Practical knowledge of steel profiles 1. Profile classification 1. Simple section steel ① square steel-hot rolled square steel and cold drawn square steel; ② Round steel-hot rolled round steel, forged round steel and cold drawn round steel; 3 wires; ④ flat steel; ⑤ Spring flat steel; ⑥ Angle steel-equilateral angle steel and unequal angle steel; ⑦ triangle steel; ⑧ Six angle steel; Pet-name ruby bow steel; Attending oval steel 2. Complex section steel ① I-beam-ordinary I-beam, light I-beam ② Channel steel-hot-rolled channel steel (ordinary channel steel and light channel steel), bent channel steel 3h-beam steel (also called wide-leg I-beam steel) ④ Special rails such as heavy rail, light rail and crane rail ⑤ Window frame steel ⑤ Sheet pile ⑤ Curved channel steel-cold-bent channel steel.

I-beam height ≥ 180mm height < 180mm.

Channel steel height ≥ 180mm, height < 180mm.

The side width of equilateral angle steel is ≥ 160mm, 50- 140mm and 20-45mm.

The side width of unequal angle steel is ≥ 160× 100mm, and the side width is ≤ 45× 28 mm

Diameter of round steel ≥90mm, 38-80mm, 10-36 mm.

The width of square steel is ≥90mm, 50-75 mm and 10-25 mm.

Flat steel width ≥ 120mm width 60- 100 mm width 12-55 mm.

Steel bar diameter ≥40 mm diameter 10-36 mm

Rivet steel diameter 10-22 mm

Other special-shaped steel products: special-shaped steel products such as track shoes and steel sheet piles, and special-shaped steel products such as composite flat steel, farm tool steel and window frame steel for small farm tools. 3. Hot rolled ribbed bar 1. Variety specification The brand of hot-rolled ribbed bar consists of HRB and the minimum yield point of the brand. H, r and b are the initials of the words Hotrolled, Ribbbed and Bars respectively. Hot rolled ribbed bars are divided into three brands: HRB335 (old brand name 20MnSi), HRB400 (brand names 20mnsini, 20msinb and 20MnTi) and HRB500. 2. Vanadium-containing Grade III threaded steel bar ① Vanadium-containing Grade III threaded steel bar has a broad market prospect. In the production process, vanadium, niobium, titanium and other alloys are added to the new grade III rebar rod (20 MnS uli, 400Mpa). Compared with ordinary grade II threaded steel bars, it has the advantages of high strength, good toughness, good weldability and good seismic performance. In the construction market of developed countries such as Europe, grade ⅲ rebar accounts for 80% of the total rebar. For example, in Britain, Germany, Australia, Japan and other countries, the use of high-strength vanadium-containing grade III rebar has reached 80-90%. 1995 The former Ministry of Metallurgy and the Ministry of Construction jointly issued a document to promote its application, and the Ministry of Construction incorporated the technical conditions of the new grade III steel bars into the national standard GBJ 10-89 Code for Design of Concrete Structures, which came into effect on 1997 10+1day. Now the new Grade III steel bars have been used in high-rise buildings, large power stations, bridges, tunnels, airports and other projects. The Ministry of Construction requires that in 2002, the newly added third-grade steel bars account for 50% of the total steel bars, and reach 80% by the end of the Tenth Five-Year Plan. However, due to insufficient publicity and promotion, the consumption is still far lower than the old grade II 335Mpa ordinary grade rebar, so it is necessary to vigorously publicize and promote the new grade III rebar.

(2) Advantages of V Ⅲ-grade rebar A. Economy: Due to its high strength, the new Ⅲ-grade rebar can save steel 10- 15% compared with Ⅱ-grade rebar, thus reducing the construction cost of construction projects. B, high strength and good toughness: after microalloying treatment, the yield point is above 400Mpa, and the tensile strength is above 570Mpa, which is 20% higher than that of secondary rebar. C. Seismic performance: Vanadium-containing steel bars have high flexural performance, aging resistance and low cycle fatigue performance, and their seismic performance is obviously superior to grade II rebar. D, easy welding: because the carbon content is less than or equal to 0.54%, it has good welding performance, is suitable for various welding methods, and the process is simple and convenient. E. Convenient construction: new grade III rebar is adopted to increase the construction gap and ensure the convenience and quality of construction. 4. Hot rolled H-beam 1. The representation of hot-rolled H-beam can be divided into three types: wide flange H-beam (HK), narrow flange H-beam (HZ) and H-beam pile (HU). Its expression method is: height H× width B× web thickness t1wing thickness t2. For example, H-beams Q235 and SS400 200×200×8× 12 are expressed as wide flange H-beams with a height of 200mm, a web thickness of 200mm and a wing thickness of 12mm, and the brand name is Q235 or SS. 2. Advantages of hot-rolled H-beam H-beam is a new type of economical building steel. H-beam section shape is economical and reasonable, and its mechanical properties are good. When rolling, all points on the cross section extend evenly and the internal stress is small. Compared with ordinary I-beam, H-beam has the advantages of large section modulus, light weight and metal saving, which can reduce the building structure by 30-40%. Because the legs are parallel inside and outside and the ends of the legs are at right angles, the welding and riveting workload can be saved by 25%. It is often used in large buildings (such as workshops and high-rise buildings) that require large bearing capacity and good cross-sectional stability, as well as bridges, ships, lifting and transportation machinery, equipment foundations, supports, foundation piles, etc. V. Cold-formed steel Cold-formed steel is an economical light-weight thin-walled steel, also known as steel cold-formed profile or cold-formed profile. It is a kind of steel with various cross-sectional shapes and sizes, which is made of hot-rolled or cold-rolled strip steel as blank and bent. Cold-formed steel has the following characteristics: 1. The section is economical and reasonable, saving materials. The section shape of cold-formed steel can be designed as required, and the structure is reasonable, and the section coefficient per unit weight is higher than that of hot-rolled steel. Under the same load, it can reduce the weight of parts and save materials. Cold-formed steel can save 38-50% metal when used in building structures, and 65-60% metal when used in agricultural machinery and vehicles. The construction is convenient and the comprehensive cost is reduced. 2. There are many varieties, which can produce all kinds of profiles with uniform wall thickness and complex cross-section shape and cold-formed steel with different materials that are difficult to produce by general hot rolling methods. 3. The products are smooth in surface, beautiful in appearance, accurate in size, and the length can be flexibly adjusted as required, all of which are supplied according to fixed length or double length, thus improving the material utilization rate. 4. It can also be combined with punching and other processes in production to meet different needs. There are many kinds of cold-formed steel, including open, semi-closed and closed sections. The main products are cold-formed channel steel, angle steel, Z-beam, cold-formed corrugated steel plate, square tube, rectangular tube, welded special-shaped steel tube and rolling shutter door. Usually produced cold-formed steel has a thickness of less than 6mm and a width of less than 500mm. Products are widely used in mining, construction, agricultural machinery, transportation, bridges, petrochemical, light industry, electronics and other industries.