What is specific gravity

What is specific gravity?

Specific gravity is also called relative density. The specific gravity of solid or liquid is the ratio of the density of the material (fully dense state) to the density (999.972 kg / m3) under standard atmospheric pressure and pure H2O at 3.98 ℃. The specific gravity of a gas refers to the ratio of the density of the gas to the air density under standard conditions. The specific gravity of a liquid or solid indicates whether they sink or float in another fluid.

Specific gravity is a dimensionless quantity, that is, specific gravity is a value without unit, which generally changes with temperature and pressure. The specific gravity is abbreviated as s.g.

Density and specific gravity

Density is a dimensional quantity, and specific gravity is a dimensionless quantity.

• ① The ratio of the dry and completely dense weight of a substance to the weight of the same volume of pure water at 4 ℃ is called the specific gravity of the substance.
• ② The weight of one thing in the whole: the proportion of China’s industry in the whole national economy is increasing year by year.
• Supplement: in some Chinese books, the weight of substances contained in unit volume is also translated into specific gravity. It can also indicate the sinking or floating of objects in water. It is generally called weight per unit volume, which can be used as a symbol ω express. ω And S.G. ω And density ρ The relationship between is ω=ρ g. Where G is the gravitational acceleration of the place. G varies with region and height, so ω It also changes with time.

Geology

In geology, the ratio of the weight of minerals to the weight of the same volume of water at 4 ℃ is called the specific gravity of minerals. If the chemical composition of the mineral contains elements with large atomic weight or the atoms or ions in the internal structure of the mineral are closely packed, the specific gravity is large; On the contrary, the specific gravity is small. The specific gravity of most minerals is between 2.5-4; Some heavy metal minerals are often between 5-8; Very few minerals (such as platinum group minerals) can reach 23.

Petroleum

Specific gravity refers to the specific gravity of American Petroleum Institute or API gravity, which is the measurement data for comparing the light cooked weight of liquid oil and water. If the API gravity of liquid oil is greater than 10, it is lighter than water and floats on water. If it is less than 10, it is heavier. Therefore, API specific gravity can be regarded as the relative density of liquid oil and water. It can also be used to compare the relative density of different liquid petroleum. For example, if one liquid oil floats above another, it means that it has low density and high API.

Reference table of specific gravity density of commonly used metal materials
The name of the material	Specific gravity (g/cm3)	The name of the material	Specific gravity (g/cm3)
Grey cast iron	6.6 ~ 7.4	White cast iron	7.4 ~ 7.7
Malleable iron	7.2 ~ 7.4	Industrial pure iron	7.87
steel	7.85	Cast steel	7.8
Mild steel (0.1% carbon)	7.85	Medium carbon steel (0.4% carbon)	7.82
High carbon steel (1% carbon)	7.81	High speed steel (tungsten 9%)	8.3
High speed steel (tungsten 18%)	8.7	Stainless steel (13% chromium)	7.75
Pure copper (red copper)	8.9	Pure nickel	8.85
silicon	2.33	lead	11.34
Industrial pure aluminum	2.71	Zinc plate	7.2
Zinc anode	7.15	Lead plate	11.37
tin	7.3	osmium	22.5
iridium	22.4	platinum	21.45
gold	19.32	tungsten	19.3
tantalum	16.6	mercury	13.6
thorium	11.5	silver	10.5
molybdenum	10.2	bismuth	9.8
cobalt	8.9	cadmium	8.65
niobium	8.57	manganese	7.43
chromium	7.19	cerium	6.9
antimony	6.68	zirconium	6.49
tellurium	6.24	vanadium	6.1
titanium	4.51	barium	3.5
beryllium	1.85	magnesium	1.74
calcium	1.55	sodium	0.97
potassium	0.86	arsenic	5.73
selenium	4.84	boron	2.34
Specific gravity density table of various alloy metals
H96 brass alloy	8.8	H90 brass alloy	8.7
H68 brass alloy	8.5	H62 brass alloy	8.5
HPb74-3 leaded brass	8.7	HPb63-3Leaded brass	8.5
Leaded brass HPb59-1	8.5	Tin brass HSn90-1	8.8
Tin brass HSn70-1	8.54	Tin brass HSn62-1	8.5
Tin brass HSn60-1	8.5	HAl77-2 aluminium brass	8.6
HAl67-2.7 –	8.5	Aluminum brass HAl60-1-1	8.5
HAl66-6-3-2 aluminum brass	8.5	HMn58-2 manganese brass	8.5
Manganese brass HMn57-3-1	8.5	Manganese brass HMn55-3-1	8.5
Iron brass HFe59-1-1	8.5	HSi80-3 silicon brass	8.5
HNi65-5 nickel silver	8.5	QSn4-3 bronze	8.8
QSn4-4-2.5 tin bronze	8.75	QSn4-4-4 tin bronze	8.9
QSn6.5-0.1 phosphor bronze	8.8	QSn6.5-0.4 phosphor bronze	8.8
QSn7-0.2 phosphor bronze	8.8	QSn4-0.3 phosphor bronze	8.9
QAl5 aluminum bronze	8.2	QAl7 aluminum bronze	7.8
QAl9-2 aluminium bronze	7.6	Aluminum bronze QAl9-4	7.5
QAl10-3-1.5 aluminum bronze	7.5	Aluminum bronze QAl10-4-4	7.5
QBe2 beryllium bronze	8.3	QBe2.15 beryllium bronze	8.3
QSi1-3 silicon bronze	8.6	Silicon bronze QSi3-1	8.4
Cadmium bronze QCd1.0	8.80	Zqsn3-12-5 Copper alloy (tin bronze)	8.69
Zqsn3-7-5-1 Copper alloy (tin bronze)	8.7	Zqsn5-5-5 Copper alloy (tin bronze)	8.84
Zqsn6-6-3 Copper alloy (tin bronze)	8.82	B5 copper alloy	8.9
B19 copper alloy	8.9	B30 copper alloy	8.9
Manganin BMn3 to 12	8.4	Manganin BMn40-1.5	8.9
Manganin BMn43-0.5	8.9	Iron cupronickel BFe30-1-1	8.9
Iron cupronickel BFe5-1	8.9	BZn15-20 argentan	8.6
BAl6-1.5 aluminum copper	8.7	NSi0.19 nickel alloy	8.85
NGu28-2.5-1.5	8.85	NMg0.1 titanium alloy	8.85
NGr9 magnesium alloy	8.7	LF2 aluminum alloy	2.68
LF3 aluminum alloy	2.67	LF5 al-alloy	2.65
LF6 aluminum alloy	2.64	LF10 aluminum alloy (Aluminum magnesium)	2.65
LF11 aluminum alloy	2.65	LF12 aluminum alloy	2.63
LF21 aluminum alloy	2.73	LY1 aluminum alloy	2.76
LY2 aluminum alloy	2.75	LY6 aluminum alloy	2.76
LY7 aluminum alloy	2.76	LY8 aluminum alloy	2.8
LY9 aluminum alloy	2.8	LY10 aluminum alloy	2.8
Of LY11 aluminum alloy	2.8	LY12 aluminum alloy	2.78
LY16 aluminum alloy	2.84	LY17 aluminum alloy	2.84
LD2 aluminum alloy	2.7	LD5 aluminum alloy	2.75
LD6 aluminum alloy	2.75	LD7 alloy	2.8
LD8 al-alloy	2.77	LD10 aluminum alloy	2.8
LC3 superduralumin	2.85	LC4 superduralumin	2.85
LC6 superduralumin	2.89	LC9 superduralumin	2.85
ZL101 alloy	2.66	ZL102Cast aluminium alloy(aluminosilicate)	2.65
ZL103 aluminum alloy	2.7	ZL104 Aluminum alloy (Aluminum-silicon)	2.65
ZL105 alloy	2.68	ZL201 Aluminum alloy (Aluminum copper)	2.78
ZL203 aluminum alloy	2.8	ZL301 aluminum alloy (Aluminum magnesium)	2.55
ZL401 alloy	2.95	ZZnAl10-5 zinc alloy	6.3
ZZnAl9-1.5 zinc alloy	6.2	Zinc alloy ZZnAl4-1	6.7
ZZnAl4 zinc alloy	6.6	ZChSnSb12-4-10 tin alloy	7.52
ZChSnSb11-6 tin alloy	7.38	ZChSnSb8-4 tin alloy	7.39
ZChSnSb4-4 tin alloy	7.34	ZChPbSb16-16-2 tin alloy	9.29
ZChPbSb15-5-3 tin alloy	9.6	ZChPbSb15-10 tin alloy	9.73
ZChPbSb15-5 tin alloy	10.04	ZChPbSb10-6 tin alloy	10.24
YG3X tungsten steel	15～15.3	YG4C tungsten steel	14.9 ~ 15.2
YG6X tungsten steel	14.6 ~ 15	YG6A tungsten steel	14.6 ~ 15
YG6 carbide	14.6 ~ 15	YG8N tungsten steel	14.5 ~ 14.9
YG8 tungsten steel	14.5 ~ 14.9	YG8C tungsten steel	14.5 ~ 14.9
YG11C tungsten steel	14～14.4	YG15 carbide	13 ~ 14.2
YW1 tungsten steel	12.6 ~ 13.5	YW2 tungsten steel	12.4 ~ 13.5
YT5 tungsten steel	12.5 ~ 13.2	YT14 tungsten steel	11.2 ~ 12
YT30 tungsten steel	9.3 ~ 9.7	YN10 hard alloy steel	6.3 or higher

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Theoretical weight scale of steel plate

Theoretical weight per square meter of steel plates (Thin, medium, thick).

The thickness of the(mm)	Theoretical weight	Thickness (mm)	Theoretical weight	Thickness (mm)	Theoretical weight	Thickness (mm)	Theoretical weight
	(kg / ㎡)		(kg / ㎡)		(kg / ㎡)		(kg / ㎡)
0.2	1.57	1.5	11.78	10	78.5	29	227.7
0.25	1.963	1.6	12.56	11	86.35	30	235.5
0.27	2.12	1.8	14.13	12	94.2	32	251.2
0.3	2.355	2	15.7	13	102.1	34	266.9
0.35	2.748	2.2	17.27	14	109.9	36	282.6
0.4	3.14	2.5	19.63	15	117.8	38	298.3
0.45	3.533	2.8	21.98	16	125.6	40	314
0.5	3.925	3	23.55	17	133.5	42	329.7
0.55	4.318	3.2	25.12	18	141.3	44	345.4
0.6	4.71	3.5	27.48	19	149.2	46	361.1
0.7	5.495	3.8	29.83	20	157	48	376.8
0.75	5.888	4	31.4	21	164.9	50	392.5
0.8	6.28	4.5	35.33	22	172.7	52	408.2
0.9	7.065	5	39.25	23	180.6	54	423.9
1	7.85	5.5	43.18	24	188.4	56	439.6
1.1	8.635	6	47.1	25	196.3	58	455.3
1.2	9.42	7	54.95	26	204.1	60	471
1.25	9.813	8	62.8	27	212	65	510.25
1.4	10.99	9	70.65	28	219.8	70	549.5
Calculation formula of theoretical weight table of iron plate: length × wide × thickness × 0.00785 = weight of each piece, 0.00785 is specific gravity.

Theoretical weight scale of round bar

General specific gravity of steel:

• Chromium steel: 15cra, 20Cr, 7.74.
• Ordinary carbon steel: Q195, Q215, Q235, Q255, Q275 7.85.
• High quality carbon steel: 05f, 08F, 15F, 10, 15, 20, 25, 30, 35, 40, 45, 50 7.85.
• Carbon tool steel: T7, T8, T9, T10, T12, T13, t7a, T8A, T9A, T10A, t11a, T12A, t13a, t8mna 7.85.
• Silicon manganese steel: 60si2nmna 7.85.

Specifications of the diameter	The weight per meterkg/m	The diameter of	The weight per meterkg/m
5.5	0.186	13	1.04
6	0.222	14	1.21
6.5	0.26	15	1.39
7	0.302	16	1.58
8	0.395	17	1.78
9	0.499	18	2.0
10	0.617	19	2.23
11	0.746	20	2.47
12	0.888	21	2.72
22	2.98	63	24.5
23	3.26	65	26
24	3.55	68	28.5
25	3.85	70	30.2
26	4.17	75	34.7
27	4.49	80	39.5
28	4.83	85	44.5
29	5.18	90	49.9
30	5.55	95	55.6
31	5.92	100	61.7
32	6.31	105	68
33	6.71	110	74.6
34	7.13	115	81.5
35	7.55	120	88.8
36	7.99	125	96.3
38	8.9	130	104
40	9.86	140	121
42	10.9	150	139
45	12.5	160	158
48	14.2	170	178
50	15.4	180	200
53	17.3	190	223
55	18.6	200	247
56	19.3	220	298
58	20.7	250	385
60	22.2
Formula: Radius x radius x 3.14 x per meter x 0.785. For example: the diameter of 6.0 steel bar,(0.03×0.03×3.14)×100×0.785=0.221841 In parentheses is the cross-sectional area,3.14 is PI,100 is centimeters (per meter), and 0.785 is specific gravity per square centimeter, so all values are converted to uniform units for calculation.

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Specification and theoretical weight of rebar

Dimensions, external weight and allowable deviation of hot-rolled wire rod (Round rebar); Theoretical weight Scale of specifications (GB/T14981).

The diameter, mm	Allowable deviation,mm			Out of roundness, mm			Cross-sectional area, mm2	Theoretical weight, Kg/m
	A level precision	Class B precision	C level precision	A level precision	Class B precision	C level precision
5.5	+ / – 0.40	+ / – 0.30	+ / – 0.15	0.50 or less. On-line calculator	0.40 or less	0.24 or less	23.8	0.187
6							28.3	0.222
6.5							33.2	0.26
7							38.5	0.302
7.5							44.2	0.347
8							50.3	0.395
8.5							56.7	0.445
9							63.6	0.499
9.5							70.9	0.556
10							78.5	0.617
10.5	+ / – 0.45	+ / – 0.35	+ / – 0.20	0.60 or less	0.48 or less	0.32 or less	86.6	0.68
11							95	0.746
11.5							104	0.815
12							113	0.888
12.5							123	0.963
13							133	1.04
13.5							143	1.12
14							154	1.21
14.5							165	1.3
15	+ / – 0.50	+ / – 0.40	+ / – 0.25	0.70 or less	0.56 or less	+ / – 0.40	177	1.39
15.5							189	1.48
16							201	1.58

Calculation formula: Radius x radius x 3.14 x per meter x 0.785.

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Size and weight specification sheet for stainless steel pipe ANSI / ASME 36.19

Stainless steel pipe dimensions, wall thickness and weight according to ASME B36.19

Stainless steel pipes are used in construction, food industry, pharmaceutical industry, petrochemical industry, automotive industry, municipal and decorative applications.

Nominal pipe size (inches)	Outside diameter		The Schedule table
			5S		10S		40S		80S
	(Millimeter)	(inches)	Thickness and weight
			mm	kg/m	mm	kg/m	mm	kg/m	mm	kg/m
			(inches)		(inches)		(inches)		(inches)
1/8	10.3	0.405	–	–	1.25	0.28	1.73	0.37	2.42	0.47
					-0.049		-0.068		-0.095
1/4	13.7	0.54	–	–	1.66	0.49	2.24	0.63	3.03	0.8
					-0.065		-0.088		-0.119
3/8	17.2	0.675	–	–	1.66	0.63	2.32	0.85	3.2	1.1
					-0.065		-0.091		-0.126
1/2	21.3	0.84	1.65	0.81	2.11	1	2.77	1.27	3.74	1.62
			-0.065		-0.083		-0.109		-0.147
3/4	26.7	1.05	1.65	1.02	2.11	1.28	2.87	1.68	3.92	2.2
			-0.065		-0.083		-0.113		-0.154
1	33.4	1.315	1.65	1.3	2.77	2.09	3.38	2.5	4.55	3.24
			-0.065		-0.109		-0.133		-0.179
1 1/4	42.2	1.66	1.65	1.66	2.77	2.69	3.56	3.39	4.86	4.47
			-0.065		-0.109		-0.14		-0.191
1 1/2	48.3	1.9	1.65	1.91	2.77	3.11	3.69	4.06	5.08	5.41
			-0.065		-0.109		-0.145		-0.2
2	60.3	2.375	1.65	2.4	2.77	3.93	3.92	5.45	5.54	7.49
			-0.065		-0.109		-0.154		-0.218
2 1/2	73	2.875	2.11	3.69	3.05	5.26	5.16	8.64	7.01	11.4
			-0.083		-0.12		-0.203		-0.276
3	88.9	3.5	2.11	4.52	3.05	6.46	5.49	11.3	7.62	15.3
			-0.083		-0.12		-0.216		-0.3
3 1/2	101.6	4	2.11	5.18	3.05	7.41	5.74	13.6	8.08	18.6
			-0.083		-0.12		-0.226		-0.318
4	114.3	4.5	2.11	5.84	3.05	8.37	6.02	16.1	8.56	22.3
			-0.083		-0.12		-0.237		-0.337
5	141.3	5.563	2.77	9.46	3.41	11.6	6.56	21.8	9.53	31
			-0.109		-0.134		-0.258		-0.375
6	168.3	6.625	2.77	11.3	3.41	13.9	7.12	28.3	10.98	42.6
			-0.109		-0.134		-0.28		-0.432
8	219.1	8.625	2.77	14.8	3.76	20	8.18	42.5	12.7	64.6
			-0.109		-0.148		-0.322		-0.5
10	273.1	10.75	3.41	22.7	4.2	27.8	9.28	60.4	12.7	81.5
			-0.134		-0.165		-0.365		-0.5
12	323.9	12.75	3.97	31.3	4.58	36.1	9.53	73.9	12.7	97.4
			-0.156		-0.18		-0.375		-0.5

Source: China Piping Solutions Provider – Yaang Pipe Industry Co., Limited (www.epowermetals.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.)

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