4140 Mild Steel Round Bar Sizes

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100 m.t.
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500000 m.t./month

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Item specifice:

Standard: AISI,JIS,GB,BS,DIN,API,EN,ASTM Technique: Hot Rolled,Cold Rolled,Cold Drawn,ERW,Forged,Saw,Extruded,EFW,Spring Shape: U Channel,Square,C Channel,Hexagonal,Round,Rectangular,Oval,LTZ
Surface Treatment: Galvanized,Coated,Copper Coated,Color Coated,Oiled,Dry,Chromed Passivation,Polished,Bright,Black,PVDF Coated Steel Grade: Q195,Q215,Q235,Q215B,Q235B,RHB335,HRB400,200 Series,300 Series,400 Series,600 Series,SS400-SS490,10#,20#,A53(A,B) Certification: ISO,SGS,BV,IBR,RoHS,CE,API,BSI,UL
Thickness: 13-300mm Length: 6-12m Net Weight: 2mt

Product Description:

4140 Mild Steel Round Bar Sizes


Product Description of 4140 Mild Steel Round Bar Sizes

1. Steel grade: ASTM4140, SCM440, 42CrMo, DIN1.7225

2. Length: 6M-12M
3. Diameter: 16mm-300mm

4. Product range: round bar, flat bar, square bar

5. Technique: Hot rolled, forged, cold drawn


Specification of 4140 Mild Steel Round Bar Sizes



Round bar




EAF + LF + VD + Forged + Heat Treatment (optional)

Length (mm)   

Max 12m

Heat treatment

Normalized / Annealed / Quenched / tempered

Flat bar



Delivery condition

Hot forged +Rough machined (black surface after Q/T)+ Turned (optional)




Ultrasonic test according to SEP 1921-84 D/d

Length (mm)   

Max 12m


Chemical Composition of 4140 Mild Steel Round Bar Sizes














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Photo Show of 4140 Mild Steel Round Bar Sizes

4140 Mild Steel Round Bar Sizes

Packing and Delivery:

Packing in bundle package, or as customer's requirements.

Delivery Detail: 45 days after receiving the deposit.


Usage and Applications of 4140 Mild Steel Round Bar Sizes

1. Steel round bar is used in a large number of architectural and engineering structures. Or it can be used in construction of plants for the production of steel house frames, high-voltage transmission towers, bridges, vehicles, boilers, containers, ships, etc.

2. And we can use this kind of product on the performance of the mechanical parts if the demand is not very high.

3. Some special material steel round bar can be used for main shaft of steamer, hummer shank, with big section and supper force.

Company Information

CNBM International Corporation is the most important trading platform of CNBM group.

Whith its advantages, CNBM International are mainly concentrate on Cement, Glass, Iron and Steel, Ceramics industries and devotes herself for supplying high qulity series of refractories as well as technical consultancies and logistics solutions.

Astm 615 Bs4449 B500B Deformed Steel RebarsAstm 615 Bs4449 B500B Deformed Steel Rebars 



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    30% TT as deposit and 70% before delivery.

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Q:What is the tensile strength of round steel bars of diameter 28?
The maximum tensile strength of material resistance uniform plastic deformation, tensile specimens before under maximum tensile stress, the deformation is uniform, but beyond the metal after the necking phenomenon began to appear, which produce concentrated deformation; for no (or very small) brittle materials with uniform plastic deformation, it reflects the fault the resistance of the material. The symbol is Rm (GB/T 228-1987, the old GB standard, the tensile strength symbol is b), the unit is MPa.
Q:What is the difference between the heat treatment of cold drawn round steel and the heat treatment of wrought round steel?
Solution treatment: the alloy can be dissolved in various phases, strengthening solid solution, improving toughness and corrosion resistance, eliminating stress and softening, so as to continue processing and forming.
Q:12mm Round steel, the material is Q235, the maximum weight can bear?
Standard Specification for hot rolled round steel is 5.5-250 mm. Among them, 5.5-25 mm small round bars are mostly supplied by straight strips. They are used as reinforcing bars, bolts and various mechanical parts. They are more than 25 millimeters of round steel. They are mainly used in the manufacture of mechanical parts or seamless steel tube billets.
Q:Are the bolts for the round bar or round steel?
If in some large-scale concrete component under the condition of some units to prevent run mode is used, the bar, the bar is the best quality, and the tensile strength is great, because the price advantage is not, it is generally not recommended to use the bar as a pull screw.
Q:Excuse me and steel disc round what is the difference?
Round steel is a solid strip of steel whose cross section is round. Its specifications are expressed in diameter, in units of millimeters (mm), such as "50mm", which means a diameter of 50 millimeters of round steel. Round bar is divided into three parts: hot rolling, forging and cold drawing. Standard Specification for hot rolled round steel is 5.5-250 mm. Where: 5.5-25 mm small round steel mostly straight bundles of supply, used for steel, bolts and various mechanical parts; greater than 25 mm round steel, seamless steel pipe is mainly used for the manufacture of mechanical parts of the tube, etc..
Q:Special steel bar steel products used to do what
But the red hardness difference of this kind of steel, that is, when the working temperature is greater than 250 degrees, the hardness and wear resistance of steel will decline rapidly, and lose their ability to work. In addition, carbon tool steels, such as those made of larger parts, are difficult to harden and easy to produce
Q:How many meters is the minimum loading surface of galvanized steel wire for grounding grid?
Refers to the galvanized flat steel width 12-300mm, thickness 4-60mm, cross section is rectangular and with pure edge of galvanized steel. Galvanized flat steel can be finished steel, also can be galvanized pipe blank and galvanized belt. With high strength, light structure: strong grid welding structure, so that it has high load, light structure, easy lifting and other features, beautiful appearance, durable.Galvanized flat steel can be used to produce iron, tools and mechanical parts, and is used as frame structures and escalators for buildings.
Q:What is the tensile strength of Q235 round steel?
Level 1, surface shape, light circle, strength code R235, grade Q235, carbon content 0.14%-0.22%. Silicon content 0.12%-0.30%. Manganese content 0.30%-0.65%, phosphorus content is equal to less than 0.045%, sulfur content is less than or equal to 0.050%,
Q:Use of stainless steel round bar?
Stainless steel round bar is a kind of long material, and it is also a kind of bar. The so-called stainless steel round bar refers to the cross section is even round long material, generally about four meters long.
Q:Lightning protection earthing zinc plating flat iron and round steel welding method, need to flat iron wrapped in round steel outside welding?
Don't need, but the welding seam area not less than round or flat between the relatively small cross section, the weld to coated with anticorrosive paint. Generally speaking, the grounding part does not use steel, galvanized L type flat iron good effect (copper strip and galvanized L type flat iron is not much, just life is long, but the cost is much higher), round only used as grid wiring.

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