What is a round bar?

What is a round bar?

What is a round bar?

Round bar is a long cylindrical metal bar, which has many industrial and commercial applications. The most common application is the shaft. The standard diameter is from 1/4 “to 24”. There may be other sizes. There are many kinds of metal types of round steel, including hot rolled steel, cold rolled steel, alloy steel, stainless steel, etc.

Classification of round bars

Classification by process

Round bar is divided into hot rolling, forging and cold drawing. The specification of hot rolled round bar is 5.5-250mm. Among them: 5.5-25 mm small round bar is mostly supplied in bundles of straight bars, commonly used as steel bars, bolts and various mechanical parts; more than 25 mm round bar is mainly used for manufacturing mechanical parts, seamless steel tube billets, etc.

Classification by chemical composition

Carbon steel can be divided into low carbon steel, medium carbon steel and high carbon steel according to chemical composition (i.e. carbon content).

Mild steel

Also known as mild steel, low carbon steel with carbon content from 0.10% to 0.30% is easy to accept all kinds of processing such as forging, welding and cutting. It is often used to manufacture chains, rivets, bolts, shafts, etc.

Medium carbon steel

Carbon steel with carbon content of 0.25% – 0.60%. There are killed steel, semi killed steel, boiling steel and other products. In addition to carbon, it can also contain a small amount of manganese (0.70% – 1.20%). According to the product quality, it can be divided into ordinary carbon structural steel and high-quality carbon structural steel. Hot working and cutting performance is good, welding performance is poor. The strength and hardness are higher than that of low carbon steel, but the plasticity and toughness are lower than that of low carbon steel. Hot rolled and cold drawn materials can be directly used without heat treatment, and they can also be used after heat treatment. The medium carbon steel after quenching and tempering has good comprehensive mechanical properties. The highest hardness is about HRC55 (hb538) and σ B is 600-1100mpa. Therefore, medium carbon steel is widely used in all kinds of medium strength applications. In addition to being used as building materials, it is also widely used in manufacturing various mechanical parts.

High carbon steel

Often called tool steel, carbon content from 0.60% to 1.70%, can be hardened and tempered. Hammers and crowbars are made of steel with carbon content of 0.75%; cutting tools such as drills, taps and reamers are made of steel with carbon content of 0.90% to 1.00%.

Classification by material

Stainless Steel Round Bars

Stainless steel round bars are highly corrosion resistant. The stainless steel will tolerate high levels of acidity and can be used in chlorine bearing environments or alkaline solutions.

Aluminum Round Bars

Aluminum round bars possess light weight and strong corrosion resistance, while being easy to machine and cut. Common applications of aluminum round bar include supports, trim, shaft, braces, pins, and dowels.

Brass Round Bars

Brass round bars are used when strength, electrical conductivity, corrosion resistance, and spark resistance are important. Brass is easy to machine and has an attractive sheen when polished. Some examples of brass bar applications are marine hardware, instruments, fasteners and fittings.

Calculation formula of round bar weight:

Weight of STEEL BAR

Weight = Density x Volume {Volume = Area x Length }

= Density of Steel x Area of Steel x Bar Length

Density of Steel = 7850 Kg/m3

Area of Steel = pi x d^2/4

= 3.14 x d^2 /4

= 0.785 d^2

Taking, Bar Length =1000 mm = 1 m

Therefore, we can calculate

Weight of Steel Bar = {7850/(1000x1000x1000)} x (3.14 x d^2 /4)x1000

= (7850 x 0.785 d^2 x 1 )/1000000

= (d^2 x 6162.25)/100000

= d^2 x 0.00616225

= d^2 x (1/0.00616225)^-1

= d^2/162.278

= d^2/162.28

Example : If we want to calculate the weight of 10 mm diameter steel bar

By the formula d^2/162.28

= 10^2/162.28

= 0.616 kg

Weight of 10mm dia. 1 meter steel bar = 0.616 kg/meter

Round Bar Weight Table, Round Bar Weight Chart

Round Bar Weight Per Foot, Round Bar Size, Round Bar Weight Per Meter, Round Bar Weight Calculator

The weight of round bar is easily calculated. Simply multiply the appropriate alloy density by the length and diameter of the required part (see worked example below).

From: silversteels.net

Metric	density (g/cm³)	x	D²	x	L	x	π/4000		weight
Example:	7.85 g/cm³	x	20 mm²	x	1 m	x	π/4000	=	2.47 kg
Imperial	density (lbs/in³)	x	D²	x	L	x	π/4		weight
Example:	0.284 lbs/in³	x	2 in²	x	12 in	x	π/4	=	10.71 lbs

For imperial weight calculations certain measurements (fractions) need to be converted to decimal inches. 

For an accurate calculation it is also important to allow for the rolled/drawn tolerances on diameter defined by the manufacturing specification please contact us for details.

Density of steel

The acknowledged density of mild steel is 7.85 g/cm3(0.284 lbs/in3). Dependent on the alloy elements added to manufactured specifications this can vary between 7.75 and 8.05 g/cm3 (0.280 and 0.291 lbs/in3).

The following chart is a sample of some of the common diameters that are available. Please contact us for details of our full product range and current stock availability.

Diameter		Weight
mm	in	kg/m	lbs/ft
6.0		0.22
	1/4		0.17
	3/8		0.38
10.0		0.62
12.0		0.89
	1/2		0.67
	3/4		1.51
20.0		2.47
	1		2.68
30.0		5.55
	1 1/2		6.02
40.0		9.87
50.0	2	15.4 2	10.71
	2 1/4		13.55
60.0		22.20
	2 1/2		16.73
70.0	2 3/4	30.21	20.24
	3		24.09
80.0		39.46
90.0	3 1/2	49.95	32.79
100.0	4	61.66	42.83
110.0		74.61
	4 1/2		54.21
120.0		88.79
	5		66.92
140.0	5 1/2	120.86	80.98
150.0	6	138.74	96.37
160.0		157.85
180.0	7	199.78	131.17
190.0	7 1/2	222.57	150.56
200.0		246.65
250.0	10	385.39	267.70
300.0		554.96
400.0		986.59

Density based on 7.85 g/cm3 (0.284 lbs/in3)

Size in mm	Average Weight
	KG/MTR	KG/FT
10	0.62	0.18
12	0.90	0.30
14	1.20	0.40
16	1.60	0.50
18	2.00	0.60
20	2.50	0.80
22	3.00	0.90
24	3.56	1.08
25	3.90	1.20
28	4.80	1.50
30	5.55	1.69
32	6.30	1.90
34	7.14	2.18
36	8.00	2.44
40	9.90	3.00
45	12.49	3.81
50	15.40	4.70
56	19.34	5.89
60	22.20	6.80
63	24.47	7.46
63.5	24.86	7.58
65	26.05	7.94
70	30.20	9.20
73	32.86	10.00
75	34.72	10.58
78	37.51	11.43
80	39.50	12.00
83	42.47	12.95
85	44.55	13.58
90	50.00	15.20
92	52.19	15.91
93	53.39	16.27
95	55.65	16.95
100	61.66	18.79
105	67.98	20.72
110	74.60	22.74
115	81.64	24.88
125	96.34	29.36

Rolling Tolerances

Size Ovality Weight Length up to 25 mm ± 0.5 mm 25 mm to 35 mm ± 0.6 mm 35 mm to 50 mm ± 0.8 mm 50 mm to 80 mm ± 1 mm 80 mm to 100 mm ± 1.3 mm 100 mm and above ± 1.6 % of diameter. ± 75 % of total tolerance specified on the size. 10 mm to 16 mm ± 5 % 16 mm and above ± 3 % For fixed length : ± 100 mm

Source: China Alloy Steel Bars Manufacturer – Yaang Pipe Industry Co., Limited (www.steeljrv.com)

(Yaang Pipe Industry is a leading manufacturer and supplier of nickel alloy and stainless steel products, including Super Duplex Stainless Steel Flanges, Stainless Steel Flanges, Stainless Steel Pipe Fittings, Stainless Steel Pipe. Yaang products are widely used in Shipbuilding, Nuclear power, Marine engineering, Petroleum, Chemical, Mining, Sewage treatment, Natural gas and Pressure vessels and other industries.)

If you want to have more information about the article or you want to share your opinion with us, contact us at sales@steeljrv.com

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