Basic knowledge of steel

1. Carbon structural steel: @ You can buy Q 195, Q2 15 steel for the production of anchor bolts, weldments, rivets and sheets.

@ Produce all kinds of section steel, steel pipes, weldments, small shafts, bolts, nuts, connecting rods, rigid ribs, etc. And buy Q235 steel.

@ Buy Q255 Q275 steel to produce keys, shafts, pins, gears, sprockets and brake levers.

2. High-quality carbon structural steel: @ Buy 08 steel or 10 steel, all kinds of stamping parts and weldments have little stress.

Buy 15 steel and 20 steel for carburized parts and welded structural parts.

@ Crankshaft, transmission shaft, gear, connecting rod and worm buy 40 steel and 45 steel.

@ Spring, spring washer, wheel and cam buy 60 steel and 65 steel.

3. Carbon tool steel: @ produces saws and chisels and buys T7 steel.

@ Punch press, woodworking tools, vise buy T8 steel T8Mn steel.

@ Tap, die, planer, drill bit, template buy T 10 T 10A steel.

@ File, scraper, reamer, gauge, etc. Buy T 12 steel.

Waiting ... I hope I can help you.

2. The most basic knowledge of steel

1, the definition of carbon steel The iron-carbon alloy of five elements with carbon content less than 2% in steel is called steel.

The five elements in carbon steel refer to the main components in chemical composition, namely C, Si, Mn, S and P (carbon, silicon, manganese, sulfur and phosphorus). Secondly, gases such as O, H, N (oxygen, hydrogen, nitrogen) will inevitably be mixed in the steelmaking process.

In addition, there must be Al in molten steel in the process of aluminum-silicon deoxidation and sedation, when Als (acid soluble aluminum) is ≥0. 020%, and the grain can be refined.

2. How is steel tempered? The main task of steelmaking is to adjust the content of carbon and alloy elements in steel to the specified range according to the quality requirements of steelmaking varieties, and reduce the content of impurities such as phosphorus, sulfur, hydrogen, oxygen and nitrogen to below the allowable level. The steelmaking process is essentially an oxidation process. Excess carbon in the furnace charge is oxidized and burned into CO gas to escape, and other Si, P and Mn are oxidized into slag.

Part of S enters the slag and part of S is discharged as SO2. When the composition and temperature of molten steel meet the process requirements, tapping can be carried out.

In order to remove excess oxygen in steel and adjust chemical composition, deoxidizer and ferroalloy or alloying elements can be added. 3. Brief introduction of converter steelmaking: The molten iron from torpedo car can be used as the main charge to be poured into converter after desulfurization, slag retention and other treatments, plus scrap steel below 10%.

Then oxygen is blown into the converter for combustion, so that excessive carbon in molten iron is oxidized and a lot of heat is released. When the probe measures that the low carbon content reaches a predetermined level, oxygen blowing is stopped and tapping is carried out. Generally, deoxidation and composition adjustment need to be carried out in ladle; Then the carbonized rice husk is thrown to the surface of molten steel to prevent the molten steel from being oxidized, and then it can be sent to the continuous casting or die casting work area.

For steel with high requirements, argon bottom blowing, RH vacuum treatment and powder spraying (spraying calcium silicate powder and modified lime) can effectively reduce gas and inclusions in steel and further reduce carbon and sulfur. After these refining measures outside the furnace, the composition can be fine-tuned to meet the demand of high-quality steel.

4. The new process of hot charging and hot delivery is adopted for the initial rolling die casting ingot, which is heated in soaking furnace, and then rolled into slab, tube billet, billet and other initial rolling products by the initial rolling mill and billet continuous rolling mill. After head cutting, tail cutting and surface cleaning, high-quality products (flame cleaning and polishing) need to be peeled and inspected, and then put into storage. At present, the products of blooming mill include blooming slab, rolled billet, billet for oxygen cylinders, round tube billet for gears, axle billet for railway vehicles and steel for plastic molds.

The initial rolled slab is mainly used as raw material to supply to the hot rolling plant; Except a part of the rolled billet, it is mainly sent to the high-speed wire rod mill as raw material. Due to the advanced nature of continuous casting slab, the demand for initial rolling slab is greatly reduced, so we turned to other products mentioned above.

5. The continuous casting slab or initial rolling slab is used as the raw material for hot continuous rolling, heated by walking beam heating furnace, descaled by high pressure water, and then enters the roughing mill. The rough rolled material enters the finishing mill after cutting the head and tail, and is rolled by computer. After finishing rolling, it is cooled by laminar flow (the cooling rate is controlled by computer), and it is coiled into straight hair coil by coiler. The head and tail of straight hair and curly hair are often tongue-shaped, fishtail-shaped, with poor accuracy in thickness, width and width, and often have defects such as wavy, folded edges and tower edges.

Its coil weight, the inner diameter of steel coil is 760 mm (generally used by pipeline industry). )

Straight hair coils are processed by cutting head, tail, trimming, multi-pass straightening and leveling finishing line, and then cut into plates or rewinds to become hot-rolled steel plates, flat hot-rolled coils, longitudinal cutting belts and other products. If the hot-rolled finished coil is taken out after pickling and oiling, it becomes a hot-rolled pickled coil.

This product has the trend of partially replacing cold-rolled plate, and the price is moderate, which is deeply loved by users. Baosteel's newly invested hot rolling pickling line is under intense construction.

6. The hot-rolled steel coil used for cold tandem rolling is used as raw material, and after the oxide scale is removed by pickling, the finished product is hot-rolled coil. Because of the cold work hardening caused by continuous cold deformation, the strength and hardness of hard rolled coil increase, and the toughness and plasticity index decrease, so the stamping performance will deteriorate and it can only be used for simple deformed parts. Because all hot dip galvanizing units are equipped with annealing units, hot rolled steel coils can be used as raw materials for hot dip galvanizing units.

Generally, the weight of hard-rolled steel coil is 6~ 13.5 tons, and the inner diameter of steel coil is 610 mm. Generally, cold-rolled steel coil should be annealed continuously (CAPL unit) or in a bell-type furnace to eliminate cold-working hardening and rolling stress and achieve the mechanical properties specified in the corresponding standards.

The surface quality, appearance and dimensional accuracy of cold-rolled steel plate are better than those of hot-rolled steel plate, and its product thickness is reduced to about 0. 18mm, so it is favored by users. Cold-rolled steel coil, as the base material of deep processing, has become a high value-added product.

Such as electro-galvanizing, hot-dip galvanizing, fingerprint-resistant electro-galvanizing, color-coated steel coils and vibration-damping composite steel plates, PVC laminated steel plates, etc. These products have excellent qualities such as beauty and corrosion resistance, and have been widely used. After annealing, the cold-rolled coil must be finished, including cutting head, tail, trimming, leveling, flattening, rewinding or longitudinal shearing.

Cold-rolled products are widely used in automobile manufacturing, household appliances, instrument switches, construction, office furniture and other industries. The weight of each bundle of steel plates is 3~5 tons.

Generally, the weight of flat coil is 3~ 10 ton/coil. The inner diameter of steel coil is 610 mm.

7. Mechanical properties of steel 7. 1 Tensile test The test of installing the tensile sample prepared according to the standard on the chuck of the tensile testing machine and slowly applying uniaxial tensile stress to the sample until the sample breaks is called tensile test. 7. 1. 1 strength The ability of a metal material to resist deformation and fracture under external force is called strength.

Strength indicators include: proportional limit, elastic limit, yield strength, tensile strength, etc. 7. The proportional limit of1.2 exerts a tensile force on the metal, and the metal has a stage where the force and deformation form a linear ratio. The maximum ultimate load Pp divided by the original cross-sectional area of the sample at this stage is the proportional limit, which is expressed by σ p..

7. 1.3 elastic limit metal is deformed by external force, and can be completely restored after external force is removed. This deformation is called elastic deformation. The maximum stress that a metal can maintain elastic deformation is called elastic limit, which is expressed by σ e.

7. 1.4 When the tensile strength sample is stretched, the stress obtained by dividing the maximum load before breaking by the original cross-sectional area is called tensile strength, which is expressed by σ b ... When the external stress of the material is greater than its tensile strength, it will break.

Therefore, the higher σb is, the greater the external stress it can bear.

3. Some knowledge about steel mills

400 of the sintering machine means that the trolley area is 400 square meters; In the 1750 blast furnace, 1750 refers to the effective volume of the blast furnace, 1750 cubic meters. Coking-the size is generally expressed by the height of the carbonization chamber and the number of holes in each coke oven; Sintering-generally, the dimensions are expressed by the trolley area of sintering machine; Ironmaking-generally using the effective volume of blast furnace to express the size; Steelmaking-generally speaking, the size is expressed by the steel output of each converter; Hot rolling-plate and strip are generally expressed by roll length; Cold rolling-like hot rolling, the size is generally expressed by the length of the coil; Oxygen generator-generally expressed in terms of oxygen production per hour; Power boiler-generally expressed by steam output per hour; Plagiarism is prohibited, and offenders will be prosecuted! Please give points, that's enough.

4. Steel expertise

Concept of steel: Steel is a kind of material which processes ingots, billets or steel into various shapes, sizes and properties we need through pressure.

Steel is an indispensable and important material for national construction and the realization of the four modernizations. Wide application range and many varieties. According to the different cross-sectional shapes, steel products are generally divided into four categories: profiles, plates, pipes and metal products. In order to facilitate the organization of steel production, order supply and good management, it is also divided into heavy rail, light rail, large steel, medium steel, small steel, cold-formed steel, high-quality steel, wire rod, medium-thick steel and thin steel. Production method of steel: most steel products are processed by pressure, so the steel products (billets, ingots, etc.) processed in this way. ) is plastically deformed.

According to the different processing temperatures of steel, it can be divided into cold working and hot working. The main processing methods of steel are: rolling: the billet passes through the gap between a pair of rotating rollers (of various shapes), and the cross section of the material is reduced and the length is increased due to the pressure of the rollers. This is the most commonly used production method for producing steel, mainly used for producing profiles, plates and pipes.

Cold rolling and hot rolling. Forged steel: a pressure processing method that uses the reciprocating impact of forging hammer or the pressure of press to change the blank into the shape and size we need.

Generally divided into free forging and die forging, it is often used to produce materials with large cross-sectional dimensions such as large profiles and cogging. Drawn steel: it is a processing method of drawing rolled metal blanks (molds, pipes, products, etc.). ) stretching through the die hole to reduce the cross section and increase the length, which is mainly used for cold working.

Extrusion: it is a processing method that steel is put into a closed extrusion cylinder, and one end is pressed, so that the steel is extruded from a specified die hole to obtain a finished product with a certain shape and size. Mostly used in the production of non-ferrous metal steel. Before introducing the classification of steel, briefly introduce the basic concepts of ferrous metal, steel and nonferrous metal.

1. ferrous metals, steel and nonferrous metals 1. Ferrous metals refer to iron and ferroalloys. Such as steel, pig iron, ferroalloy, cast iron, etc.

Both steel and pig iron are alloys based on iron and with carbon as the main additive element, which are collectively called iron-carbon alloys. Pig iron refers to the products made of iron ore smelted by blast furnace, which is mainly used for steelmaking and casting.

Cast pig iron is smelted in a smelting furnace to obtain cast iron (liquid), and the liquid cast iron is cast into cast steel, which is called cast iron. Ferroalloy is an alloy composed of iron and carbon, silicon, manganese, chromium, titanium and other elements. Ferroalloy is one of the raw materials for steelmaking, which is used as deoxidizer and alloying element additive for steel.

2. Put pig iron for steelmaking into a steelmaking furnace and smelt it according to a certain process to obtain steel. Iron and steel products include direct casting of steel ingots, continuous casting billets and various steel castings.

Generally speaking, steel refers to steel rolled into various shapes. Steel belongs to ferrous metal, but steel is not completely equal to ferrous metal.

3. Non-ferrous metals, also known as non-ferrous metals, refer to metals and alloys other than ferrous metals, such as copper, tin, lead, zinc, aluminum, brass, bronze, aluminum alloys and bearing alloys. In addition, chromium, nickel, manganese, molybdenum, cobalt, vanadium, tungsten and titanium are also used in industry. These metals are mainly used as alloy additives to improve the properties of metals, among which tungsten, titanium and molybdenum are mostly used to produce cemented carbide for cutting tools.

These nonferrous metals are called industrial metals, in addition to precious metals: platinum, gold, silver and rare metals, including radioactive uranium and radium. /2. Classification of steel Steel is an iron-carbon alloy with carbon content between 0.04% and 2.3%.

In order to ensure its toughness and plasticity, the carbon content generally does not exceed 1.7%. Besides iron and carbon, the main elements of steel are silicon, manganese, sulfur and phosphorus.

There are many ways to classify steel products, mainly as follows: 1. Classification by quality (1) ordinary steel (P≤0.045%, S≤0.050%) (2) high-quality steel (both p and s ≤0.035%) (3) high-quality steel. B medium carbon steel (c ≤ 0.25 ~ 0.60%); C. high carbon steel (C≤0.60%). (2) Alloy steel: a. Low alloy steel (total content of alloy elements ≤ 5%); B medium alloy steel (the total content of alloying elements is 5-10%); C. high alloy steel (total content of alloying elements >; 10%)。

3. Steel products are classified according to forming methods: (1) forged steel; (2) cast steel; (3) hot rolled steel; (4) cold-drawn steel bars. 4. Steel is classified as (1) annealing according to metallographic structure: a. Submerged arc welding steel (ferrite+pearlite); B.*** steel precipitation (pearlite); C. steel precipitates through steel (pearlite+cementite); D ledeburite steel (pearlite+cementite).

(2) normalizing: a. pearlite steel; B. bainite steel; C. martensitic steel; Austenite steel. (3) Steel 5 without phase transformation or partial phase transformation. Classification by use (1) steel for building and engineering: a. ordinary carbon structural steel; B. low alloy structural steel; C. steel bars.

(2) Structural steel: a. Steel for machinery manufacturing: (a) high-quality structural steel; (b) Surface hardened structural steel: including carburized steel, ammoniated steel and surface hardened steel; (c) free-cutting structural steel; 4. Steel for cold plastic forming: including cold stamping steel and cold heading steel; B. spring steel; Bearing steel. (3) Tool steel: a. Carbon tool steel; B. alloy tool steel; C. high-speed tool steel.

(4) Special performance steel: a. Stainless and acid-resistant steel; B. Heat-resistant steel: including oxidation-resistant steel, heat-resistant steel and valve steel; C. electrothermal alloy steel; D. wear-resistant steel; E. low temperature steel; Electrical steel. (5) Professional steel-such as steel for bridges, ships, boilers, pressure vessels and agricultural machinery.

6. Comprehensive classification (1) Ordinary steel A. Carbon structural steel: (a)Q 195 (b)Q2 15(A, B) (c)Q235(A, b, C) (d)Q255(A, d). B. low alloy structural steel; C. ordinary structural steel for special purposes. (2) High-quality steel (including advanced high-quality steel): a. Structural steel: (a) High-quality carbon structural steel (b) Alloy structural steel (c) Spring steel (d) Free-cutting steel (e) Bearing steel (f) Special-purpose high-quality structural steel; B tool steel: (a) carbon tool steel (b) alloy tool steel (c) high-speed tool steel; C. Special performance steel: (a) stainless acid-resistant steel (b) heat-resistant steel (c) electrothermal alloy steel (d) electrical steel (e) high manganese wear-resistant steel.

7. Classification of smelting methods (1).

5. Steel related knowledge

Tensile strength:

When steel yields to a certain extent, its deformation resistance is improved again due to the rearrangement of internal grains. At this time, although the deformation develops rapidly, it can only be improved with the increase of stress until the stress reaches the maximum. After that, the ability of steel to resist deformation is obviously reduced, and a large plastic deformation occurs at the weakest point, and the cross section of the sample is rapidly reduced, and necking occurs until it breaks. The maximum stress value (corresponding to point B) of steel before tensile fracture is called strength limit or tensile strength;

Elongation refers to the maximum relative deformation rate of waterproofing membrane when it breaks at a certain strain rate.

There are relevant regulations in the national standard, and violation of the regulations will have serious consequences for the building.

Yield strength:

When the stress exceeds the elastic limit, the deformation increases rapidly. At this time, besides elastic deformation, some plastic deformation will occur. When the stress reaches point B, the plastic strain increases sharply and a small wave platform appears on the curve. This phenomenon is called yield. The maximum and minimum stresses at this stage are called the upper yield point and the lower yield point respectively. Because the value of the lower yield point is relatively stable, it is called yield point or yield strength as an index of material resistance.

6. Practical knowledge of steel.

The following is the national standard of steel, I hope it will help you.

I introduction 1. Crane track (GB3426-82) 10. Carbon covered electrode steel wire rod (GB3429-82) 2. Railway rail (GB 2585-81)11. Structural steel for bridge. Light rail GB11264-8912. Hot rolled carbon steel for bridge construction (GB7 14-65) 4. Hot rolled steel bar (GB 1499-84) 13. Electric welding anchor. 8+04. Mining steel (GB34 14-82) 6. Cold heading steel (YB534-65) 15. Agricultural composite steel (GB 1 199-75) 7. Cold heading and hot heading riveted rebar (GB 75438) 16. Steel for agricultural machinery. Hollow steel for drilling drill pipe (GB1301-87)17. Section steel for machine-made plowshare (GB 1465-78) 9. Cold-drawn high-quality structural steel (GB 3078-78) plate 1. High quality carbon thick steel plate (GB711-88) 21. Enamel hot rolled steel plate (YB474-64) 2. Structural steel for shipbuilding (GB7 12-88) 22. Hot rolled steel plate for valve plate of air compressor (GB 7 12-88)) 23. Hot rolled carbon structural steel plate for 200-liter oil drums (GB3276-89) 4. Low alloy thick steel plate for low temperature pressure vessels (GB353 1-83) 24. Hot dip galvanized steel sheet and strip. Weathering structural steel plate 25. Tinned steel plate and steel strip. Hot-rolled high-quality carbon structural steel plate for automobile (GB 3275-82) 24. Hot rolled steel plate for automobile beam (GB3273-89) 27. Classification and code of No.8 steel strip. Carbon steel and low alloy steel plate for boiler (GB7 13-88) 28. Cold-rolled steel strip of high quality carbon structural steel (GB3522-83) 9. Carbon steel and ordinary low alloy steel plates for bridges (Yb 168-77) 10. Alloy structural steel plate for aviation (YB540-65) 30. Hot-rolled carbon steel and low-alloy steel wide strip and plate for bicycles (GB3645-89) 1 1. Stainless steel hot rolled thick steel plate (GB4237-84) 3 1. Cold rolled carbon for bicycles. Thin rolled steel plate (GB3280-84) 32. Cold rolled steel strip for bicycle chain (GB3643-83) 13. Calculation method of stainless steel plate weight (GB4229-84) 33. Cold rolled steel strip for bicycles (GB3646-89) 14. Heat-resistant steel hot-rolled steel plate and cold-rolled steel plate. Hot rolled steel strip and flat steel 15. Alloy structural steel sheet (GB5067-85) 35. Cold-rolled steel strip for shaving blades (GB3527-89) 16. Spring steel hot rolled steel plate (GB3279-89) 36. Cold rolled strip of spring steel and tool steel (GB3525-83) 17. High quality carbon structural steel plate and strip (GB7 10-88) 37. Cold rolled stainless steel strip and heat resistant steel strip (GB4239-84) 18. Hot rolled steel strip and steel strip for general structure (GB 2565438 38+02-85) 19. Cold-rolled steel sheet and strip for deep drawing (GB52 13-85) 39. Cold rolled electrical steel strip (sheet) (GB252 1-88) 20. Pickled steel plate (Yb178-65) 438+01255-89) III. Pipeline 1. Seamless steel pipe for structure (GB8 162-87) 8. Petroleum butt welding drill pipe, drill collar, kelly and casing (YB69 1-70) 2. Precision seamless cold drawing or cold rolling. Oil pipe and its joint (YB235-70) 3. High pressure seamless steel pipe for fertilizer equipment (GB6479-86) 10. Seamless steel pipe for petroleum cracking (GB9948-88) 4. Seamless steel pipe for boiler (GB 53 10-85) 165438. Low and medium pressure seamless steel pipe for boiler (GB 3087-82) (Yb (t) 33-86)12. Seamless steel pipes for diesel engines, ships and bearings. Seamless steel pipe for automobile shaft sleeve (GB3088-82) 13. Stainless steel seamless steel pipe (GB2270-80) 7. Seamless steel pipe for diamond core drilling (GB3423-82) 14. Stainless steel and acid-resistant steel extremely thin-walled small-diameter seamless steel pipe (GB 3089-88) 15. Welded steel pipe with a diameter of 5- 152mm (YB242-63) IV. Wire material 1. Welding steel wire (GB 1300-77)(GB4242-84). 13. General galvanized low-carbon steel wire (GB308 1-82) 2. Carbon spring steel wire (GB4357-89) 14. General purpose galvanized low carbon steel wire (GB9972-88) 3. Chromium-vanadium spring steel wire (GB 52 19- 4. Important spring steel wire (GB4359-89) 16. Galvanized low carbon steel wire (GB346-84) 5 for communication wires. Carbon structural steel wire for bearing cage (GB5955-86) 17. Steel wire for rope making (GB 1 178) +08. Galvanized steel wire is steel-cored aluminum stranded wire (GB3428-82) 7. Alloy structural steel wire for cold heading (GB5954-86) 19. Silver bright steel bars (YB467-64)(YB468-64) of free-cutting steel and carbon tool steel for watches. 8. Steel wire for spokes (GB 120 1-89) 20. Silver bright steel bar and stainless steel and cobalt-based alloy round wire (YB470-64)(YB47 1-64) for watches. 9. Alloy structural steel wire (GB3079-82) 2 1. High quality carbon structural steel wire (GB3206-82) 10. High speed tool steel wire (GB3080-82) 22. Carbon tool steel wire (GB 5952-86) 165438. ) 12. Steel wire for prestressed concrete (GB5223-85) 24. Recommended steel grade for welding steel wire (YB/Z 1 1-76) V. Brand and application of high temperature resistance, corrosion resistance and precision alloy 1. Superalloy (GBN 175

7. Steel knowledge

Size and weight of steel (I) Length and size of steel The length and size of steel is the most basic size among all kinds of steel, which refers to the length, width, height, diameter, radius, inner diameter, outer diameter and wall thickness of steel.

The legal units of measurement for steel length are meters (m), centimeters (cm) and millimeters (mm). In current customs, it is also expressed in inches (), but it is not a legal unit of measurement.

1. Cutting to length is an effective measure to save materials. Range size means that the length or the length multiplied by the width is not less than a certain size, or the length or the length multiplied by the width is delivered within the size range.

The production unit can produce and supply according to this size requirement. 2. indefinite ruler (usually length) Any product size (length or width) is within the range specified by the standard, but it does not require a fixed size, which is called indefinite ruler.

The indefinite length is also called the constant length (gauge). Metal materials with indefinite delivery length can be delivered within the specified length.

For example, ordinary round steel with a length of less than 25mm is usually defined as 4- 10m, and round steel with a length within this range can be delivered. 3. If it is cut to a fixed size according to the requirements of the order, it is called cut to length.

When delivering by length, the delivered metal materials must have the length specified by the buyer in the order contract. For example, if the contract stipulates that the goods should be delivered in a fixed length of 5m, then all the delivered materials must be 5m long, and any goods shorter than 5m or longer than 5m are unqualified.

But in fact, it is impossible for all deliveries to be 5m long, so it is stipulated that positive deviation is allowed and negative deviation is not allowed. 4. Double scales are called double scales when they are cut into integral multiples according to the fixed size required by the order.

When the goods are delivered in double length, the length of the delivered metal material must be an integer multiple of the length (called single length) specified by the buyer in the order contract (plus kerf). For example, in the order contract, the buyer requires the length of a single piece to be 2m, so the length is 4m when it is cut into double length and 6m when it is cut into triple length, and one or two slits are added respectively.

The number of incisions is specified in the standard. Double long delivery only allows positive deviation, not negative deviation.

5. A short ruler whose length is less than the lower limit of indefinite ruler specified in the standard but not less than the shortest allowable length is called a short ruler. As stipulated in the Standard for Steel Pipes for Water Gas Transportation, each batch is allowed to have 10% short steel pipes of 2-4m (calculated by the number of pipes).

4m is the lower limit of indefinite length, and the shortest allowable length is 2m. 6. A narrow ruler whose width is less than the lower limit of the width of the indefinite ruler stipulated in the standard, but not less than the narrowest width allowed, is called a narrow ruler.

When delivering goods according to the narrow scale, we must pay attention to the narrow scale ratio and the narrowest scale specified in the relevant standards. (2) The length dimension of steel is 1. Length dimension of section steel (1) The standard length of train track is 12.5m and 25m..

⑵ The dimensions of round steel, steel wire and steel wire are calibrated in millimeters (mm) of diameter d ... (3) The dimensions of square steel are calibrated by millimeters (mm) of side length A. ..

(4) The dimensions of hexagonal steel and octagonal steel are calibrated by the millimeters (mm) of the distance s from the opposite side. 5] The dimensions of flat steel are calibrated in millimeters (mm) of width b and thickness d. ..

[6] The dimensions of I-beam and channel steel are calibrated by the mm of waist height H, leg width B and waist thickness D. Once the dimensions of equilateral angle steel are calibrated by the mm of equal side width B and side thickness D ..

The size of unequal angle steel is calibrated by the side widths b and b and the mm of the side thickness d. ⑻ The dimension of H-beam is calibrated by web height h, wing width b, web thickness t 1 and the mm of wing thickness t2.

2. The length dimension of steel plate and steel strip (1) is usually calibrated by the mm of the thickness d of steel plate. The steel strip is calibrated by the number of millimeters (mm) of the width b and thickness d of the steel strip. (2) The size of a single steel plate is different. For example, hot rolled steel plate, thickness 1mm, width 600* length 2000 mm 650 * 2000 mm 700 *1420 mm; 750 * 1500mm； 900 * 1800mm； 1000*2000 mm, etc.

3. The length and size of the steel pipe (1) are usually calibrated by the number of millimeters (mm) of the outer diameter d, inner diameter and wall thickness s of the steel pipe. (2) Each steel pipe has different sizes, such as 15 kinds of seamless steel pipes with an outer diameter of 50mm and a wall thickness of 2.5- 10mm; Or two kinds with the same wall thickness of 5mm and outer diameter of 32-195 mm.

Another example is welded steel pipes. Ordinary steel pipes have a nominal diameter of 25mm, a wall thickness of 3.25mm and a thickened steel pipe of 4mm. (3) Steel weight 1. Theoretical weight of steel The theoretical weight of steel is calculated according to the nominal size and density of steel (previously called specific gravity), which is called theoretical weight.

This is directly related to the length, cross-sectional area and allowable deviation of steel. Due to the allowable deviation of steel in the manufacturing process, the theoretical weight calculated by the formula is different from the actual weight, so it is only used as a reference for estimation.

2. Actual weight of steel The actual weight of steel refers to the weight of steel obtained by actual weighing (weighing), which is called actual weight. The actual weight is more accurate than the theoretical weight.

3. Calculation method of steel weight (1) Gross weight is the symmetry of "net weight", which is the total weight of steel itself and packaging materials. When calculating freight, a transport enterprise shall calculate the freight by gross weight.

However, the purchase and sale of steel products are calculated by net weight. ⑵ Net weight is the symmetry of "gross weight".

The actual weight, that is, the gross weight of steel minus the weight of packaging materials, is called net weight. In the purchase and sale of steel, it is generally calculated by net weight.

(3) Tare weight of steel packaging materials is called tare weight. (4) Weight ton is the weight unit used when calculating freight according to the gross weight of steel.

Its legal unit of measurement is tons (1000kg), and there are long tons (British weight unit 10 16. 16kg) and short tons (American weight unit 907. 18kg). 5] The billing weight is also called "billing ton" or "freight ton".

The weight of steel collected by the transportation department. Different modes of transportation have different calculation standards and methods.

Such as railway vehicle transportation, the marked load of second-hand trucks is generally used as the charging weight. Road transport charges freight according to the vehicle's deadweight tonnage.

Railway and highway are less than one load, and the minimum billing weight is a few kilograms gross weight, which will be rounded off when it is insufficient. (IV) Calculation of theoretical weight of steel The unit of measurement for calculating the theoretical weight of steel is kilograms (kg).

Its basic formula is: w (weight, kg) = F (cross-sectional area mm2 )* L (length m )*ρ (density, g/cm3) *11000. If you really want to work in steel, you should try to visit more steel websites.