Inconel 625 Pipe

Inconel alloy 625 is a non-magnetic, corrosion and oxidation resistant, nickel-chromium based solid solution strengthened deformed superalloy.

Inconel 625 is extremely resistant to a variety of unusually severe corrosive environments, including high temperature effects such as oxidation and carburization, including corrosion. Because of the solid solution of the refractory Co and Mo in a Nickel-Chromium matrix, provides 625 an outstanding strength and toughness in high temperature ranging from low up to 2000°F (1093°C).

The Inconel 625 Pipe is also able to withstand highly acidic conditions. Moreover, the ASME Sb 444 UNS N06625 Alloy 625 Pipes exhibits properties such as high tensile strength as well as good creep resistance and good weldable properties, therefore, these pipes can be used in nuclear base applications. Inconel 625 Welded Pipes are a superalloy that has been solid solution strengthened for use in both elevated temperature and high pressured applications. The pipes produced under ASTM B444 UNS N06625 specification often indicates that these pipes have a seamless construction.

What grade is Inconel 625 pipe?

Inconel 625 pipe is typically referred to as "Grade 1" when in an annealed condition, and "Grade 2" when in a solution annealed condition, according to the ASTM B444 standard; both are considered "Inconel 625" and designated as UNS N06625 in the material specification.

Key points about Inconel 625 grades:

Grade 1: Most commonly used, annealed condition.

Grade 2: Solution annealed condition, often used for applications requiring specific properties.

Is Inconel 625 a stainless steel?

No, Inconel 625 is not considered a stainless steel; it is a nickel-based superalloy, meaning its primary component is nickel, not iron which is the base material for stainless steel, and it has superior corrosion resistance, particularly at high temperatures, making it suitable for extreme environments where stainless steel might not perform as well.

Definition level

Stainless steel: Stainless steel refers to steel that does not rust in weakly corrosive media such as the atmosphere and fresh water, and is an iron-based alloy. Its main feature is that it has corrosion resistance under certain conditions and is mainly composed of iron.

Inconel 625: It is a nickel-based alloy, which is an alloy material formed by adding a variety of other elements based on nickel. It is not based on iron, so it is distinguished from stainless steel by definition.

Performance level

Stainless steel: Different types of stainless steel have different performances, but generally have good corrosion resistance in general atmosphere, fresh water, weak acid and alkali environments. However, in some extreme corrosive environments, such as strong oxidizing acids, high temperature and high pressure sulfur-containing environments, the corrosion resistance of stainless steel may be challenged.

Inconel 625: It has better comprehensive performance. It not only performs well in various corrosive environments, such as being able to resist corrosion from seawater, various acids (sulfuric acid, phosphoric acid, etc.) and alkaline solutions, but also has good high temperature strength and oxidation resistance. It can be used at temperatures up to 1093°C (2000°F) and can maintain high strength and creep resistance at high temperatures.

ASTM B444 UNS N06625 Pipe Standard Specification

Standard Scope

This specification covers nickel-chromium-molybdenum-columbium alloys (UNS N06625 and UNS N06852) and nickel-chromium-molybdenum-silicon alloy (UNS N06219) in the form of cold-worked seamless pipe and tube. The general requirements for pipe and tube are covered by Specification B829.

Referenced Documents

B829 Specification for General Requirements for Nickel and Nickel Alloys Seamless Pipe and Tube

B880 Specification for General Requirements for Chemical Check Analysis Limits for Nickel, Nickel Alloys and Cobalt Alloys

B899 Terminology Relating to Non-ferrous Metals and Alloys

E112 Test Methods for Determining Average Grain Size

G28 Test Methods for Detecting Susceptibility to Inter granular Corrosion in Wrought, Nickel-Rich, Chromium Bearing Alloys

G48 Test Methods for Pitting and Crevice Corrosion Resistance of Stainless Steels and Related Alloys by Use of Ferric Chloride Solution

Materials and Manufacture

Material furnished under this specification shall conform to the applicable requirements of Specification B829 unless otherwise provided herein.

UNS N06625 products are furnished in two grades of different heat-treated conditions:

Grade 1 (annealed)—Material is normally employed in service temperatures up to 1100 °F (593 °C).

Grade 2 (solution annealed)—Material is normally employed in service temperatures above 1100 °F (593 °C) when resistance to creep and rupture is required.

NOTE 1—Hot-working or reannealing may change properties significantly, depending on working history and temperatures.

Alloys UNS N06219 and UNS N06852 are supplied in the solution annealed condition only.

Test Methods

Hydrostatic Test—Each pipe or tube with an outside diameter 1 ⁄8 in. (3 mm) and larger and with wall thickness of 0.015 in. (0.38 mm) and over shall be tested in accordance with Specification B829. The allowable fiber stress for material in the condition furnished, is as follows:

UNS N06625: Grade 1—30 000 psi (207 MPa)

UNS N06625: Grade 2—25 000 psi (172 MPa)

Inconel 625 Pipes & Tubes Chemical Composition (%):

Nickel	58% min
Chromium	20% to 23%
Molybdenum	8% to 10%
Iron	5.0% max
Carbon	0.10% max
Manganese	0.50% max
Silicon	0.50% max
Phosphorus	0.015% max
Sulfur	0.015% max
Aluminum	0.40% max
Titanium	0.40% max
Columbium + tantalum	3.15% to 4.15%

Inconel 625 Pipes & Tubes  Mechanical Properties

TABLE 1 Room Temperature Tensile Properties and Heat
TreatmentA,B
Condition	Tensile Strength, min, ksi (MPa)C	Yield Strength (0.2 % offset), min, ksi (MPa)C	Elongation in 2 in. or 50.8 mm (or 4 D), min, %
Alloy N06625
Grade 1 (annealed)D	120 (827)	60 (414)	30
Grade 2 (solution annealed)E	100 (690)	40 (276)	30

A  Not applicable to outside diameters under 1 ⁄8 in. (3.2 mm) and to wall thicknesses under 0.015 in. (0.38 mm).

B  Hot forming quality pipe and tubing is furnished to chemical requirements and surface inspection only. No tensile properties are required.

C  The minimum strength values apply only to tubing in straight lengths.

D  Annealed at 1600 °F (871 °C) minimum.

E  Solution annealed at 2000 °F (1093 °C) minimum, with or without subsequent stabilization anneal at 1800 °F (982 °C) minimum to increase resistance to sensitization.

What are the disadvantages of Inconel?

Although Inconel alloy has many excellent properties, it also has some disadvantages, as follows:

➪ Difficult processing

➪ Fabrication and Manufacturing Complexity

➪ Susceptibility to Certain Chemicals

➪ Work Hardening

➪ Machining challenges

➪ Complex hot processing

➪ Welding problems

➪ Hot cracking tendency

➪ Porosity and inclusions

➪ High Raw material cost

➪ Limited resistance to certain specific corrosion

➪ Specific strong corrosion environment

➪ Susceptibility to crevice corrosion and stress corrosion cracking

What are the advantages of Inconel?

Inconel is a series of nickel-based alloys. These alloys have many outstanding advantages, making them widely used in many fields:

➪ Excellent corrosion resistance

➪ Tolerance to oxidizing environments

➪ Adaptability to various corrosive environments

➪ Good high temperature performance

➪ High temperature stability

➪ Excellent low temperature performance

➪ Low temperature dimensional stability

➪ Good processing performance

➪ Hot processing performance

➪ Cold processing performance

➪ High weldability

Alloy 625 Pipe Dimension and Permissible Variations

Inconel 625 Pipe Dimensions

NOTE 1—The decimal thickness listed for the respective pipe sizes represents their nominal or average wall dimensions.
NPS	Outside Diameter				Nominal Wall Thickness
Designator	in.	mm	Schedule 5SA		Schedule 10SA		Schedule 40S		Schedule 80S
			in.	mm	in.	mm	in.	mm	in.	mm
1/8	0.405	10.29			0.049	1.24	0.068	1.73	0.095	2.41
1/4	0.540	13.72			0.065	1.65	0.088	2.24	0.119	3.02
3/8	0.675	17.15			0.065	1.65	0.091	2.31	0.126	3.20
1/2	0.840	21.34	0.065	1.65	0.083	2.11	0.109	2.77	0.147	3.73
3/4	1.050	26.67	0.065	1.65	0.083	2.11	0.113	2.87	0.154	3.91
1	1.315	33.40	0.065	1.65	0.109	2.77	0.133	3.38	0.179	4.55
1 1/4	1.660	42.16	0.065	1.65	0.109	2.77	0.140	3.56	0.191	4.85
1 1/2	1.900	48.26	0.065	1.65	0.109	2.77	0.145	3.68	0.200	5.08
2	2.375	60.33	0.065	1.65	0.100	2.77	0.154	3.91	0.218	5.54
2 1/2	2.875	73.03	0.083	2.11	0.120	3.05	0.203	5.16	0.276	7.01
3	3.500	88.90	0.083	2.11	0.120	3.05	0.216	5.49	0.300	7.62
4	4.000	101.60	0.083	2.11	0.120	3.05	0.226	5.74	0.318	8.08
4	4.500	114.30	0.083	2.11	0.120	3.05	0.237	6.02	0.337	8.56
5	5.563	141.30	0.109	2.77	0.134	3.40	0.258	6.55	0.375	9.52
6	6.625	168.28	0.109	2.77	0.134	3.40	0.280	7.11	0.432	10.97
8	8.625	219.08	0.109	2.77	0.148	3.76	0.322	8.18	0.500	12.70
10	10.750	273.05	0.134	3.40	0.165	4.19	0.365	9.27	0.500B	12.70B
12	12.750	323.85	0.156	3.96	0.180	4.57	0.375B	9.52B	0.500B	12.70B

ASTM B444 UNS N06625 Permissible Variations

TABLE 2  Permissible Variations for Outside Diameter and Wall Thickness of Seamless Cold-Worked Pipe and TubeA,B
Nominal Outside Diameter, in. (mm)	Permissible Variations				Thickness of Specified Minimum Wall, %
	Outside Diameter,             in. (mm)		Thickness of Specified Nominal Wall, %		Plus	Minus
	Plus	Minus	Plus	Minus
Over 0.400 (10) to 5⁄8  (16), excl	0.005 (0.13)	0.005 (0.13)	15.0	15.0	30	0
5⁄8  (16) to 11⁄2  (38), incl	0.0075 (0.19)	0.0075 (0.19)	10.0	10.0	22	0
Over 11⁄2  (38) to 3 (76), incl	0.010 (0.25)	0.010 (0.25)	10.0	10.0	22	0
Over 3 (76) to 41⁄2  (114), incl	0.015 (0.38)	0.015 (0.38)	10.0	10.0	22	0
Over 41⁄2  (114) to 6 (152), incl	0.020 (0.51)	0.020 (0.51)	12.5	12.5	28	0
Over 6 (152) to 65⁄8  (168), incl	0.025 (0.64)	0.025 (0.64)	12.5	12.5	28	0
Over 65⁄8  (168) to 85⁄8  (219), incl	0.031 (0.79)	0.031 (0.79)	12.5	12.5	28	0
Over 8.625 (219) to 14 (356), incl	0.062 (1.57)	0.031 (0.79)	15.0	12.5	30.0	0.0
Over 14 (356) to 24 (610), incl	0.125 (3.18)	0.031 (0.79)	15.0	12.5	30.0	0.0

A  Ovality—The permissible variations in this table apply to individual measurements, including out-of-roundness (ovality) except for the following:

For pipe and tube having a nominal wall thickness of 3 % or less of the nominal outside diameter, the mean outside diameter shall conform to the permissible variations of this table and individual measurements (including ovality) shall conform to the plus and minus values of the table, with the values increased by 0.5 % of the nominal outside diameter.

For pipe and tube over 41⁄2 in. (114 mm) in outside diameter with a nominal wall thickness greater than 3 % of the nominal outside diameter, the mean outside diameter shall conform to the permissible variations of this table and individual measurements shall not exceed twice the permissible variations of the table.

B   Eccentricity—The permissible variations in this table apply to individual measurements including eccentricity

TABLE 3  Permissible Variations for Outside Diameter and Wall Thickness of Hot-Finished TubeA
Nominal Outsider Diameter,  in. (mm)	Permissible Variations
	Outside Diameter or Inside         Diameter, in. (mm)		% of Thickness of Specified Nominal Wall		% of Thickness of Specific Minimum Wall
	+	−	+	−	+	−
3⁄4  (19) to 11⁄2  (38), incl	0.015 (0.4)	0.031 (0.8)	12.5	12.5	28.5	0
Over 11⁄2  (38.1) to 4 (102), incl	0.031 (0.8)	0.031 (0.8)	12.5	12.5	28.5	0
Over 4 (102) to 91⁄4  (235), incl	0.062 (1.6)	0.031 (0.8)	12.5	12.5	28.5	0

A   Ovality—Tube 5 in. (127 mm) and under in outside diameter the tolerance on the outside diameter applies for individual measurements and includes ovality. Tube over 5 in. (127 mm) in outside diameter the mean outside diameter shall conform to the permissible variations of this table and individual measurements shall not exceed twice the permissible variations of this table.

Inconel Alloy 625 VS Inconel Alloy 718

Overview

Inconel 718 (UNS N07718, W.Nr. 2.4668) is a high strength, corrosion resistant nickel-chromium alloy for use in temperatures from -423°F to 1300°F. It can manufacture various parts with complex shapes, and has been widely used in the above temperature range in aerospace, nuclear energy, petroleum industry and extrusion dies. The alloy is a precipitation-strengthened alloy with a density of 8.19g/cm³.

INCONEL 625 (UNS N06625 , W.Nr. 2.4856) is a solid solution strengthened nickel base wrought superalloy with excellent corrosion resistance and high oxidation properties, good tensile and fatigue properties from low temperature to 1800°F , and resistant to stress corrosion in a salt spray atmosphere. Therefore, it can be widely used in the manufacture of aero-engine parts, aerospace structural parts and chemical equipment, with a density of 8.44 g/cm³.

Mechanical properties

Strength: Inconel 718 can obtain higher strength through aging treatment, especially in medium temperature (about 650℃) environment, the yield strength and tensile strength are excellent, and it is widely used in parts that bear high stress.

Toughness: Inconel 625 has good toughness and ductility, can maintain good mechanical properties in a wide temperature range, and will not become brittle even in low temperature environment.

Corrosion resistance

Inconel 718: It has good corrosion resistance in general oxidation and reduction environments, but compared with Inconel 625, its corrosion resistance in strong corrosive environments (such as environments containing chloride ions) is slightly weaker.

Inconel 625: It has excellent corrosion resistance and can resist corrosion from a variety of media, including seawater, various acids (such as sulfuric acid, phosphoric acid, etc.) and chloride solutions. It performs well in strong corrosive environments such as marine engineering and chemical industry.

High temperature performance

Inconel 718: It can maintain good strength and creep resistance at around 650℃, and is suitable for medium temperature and high temperature application scenarios.

Inconel 625: It can maintain its anti-oxidation and anti-hot corrosion properties at higher temperatures (about 980°C), and has more advantages in high temperature and high corrosion environments.

Specialty Metals

INCONEL® Pipe, Valves, Fittings & Flanges:

Trade Name	Inconel® 625
UNS #	N06625
Seamless Pipe / Tube	B/SB444
Welded Pipe / Tube	B/SB705, B474, B/SB704
Buttweld Fittings	B/SB366 Grade WPNCMC
Forged Valves	B/SB564
Forged Fittings	B/SB564
Flanges	B/SB564
Plate	B/SB443
Cast Steel Valves	A/SA494
	UNS N26625
Grade	CW6MC

Inconel 625 Pipes & Tubes Features:

● Excellent oxidation resistance

● High breaking strength, creep strength and tensile strength

● Excellent weldability and brazeability

● Best Fatigue Strength and Thermal Fatigue Strength

● Resistance to chloride ion stress corrosion cracking

What is Inconel 625 used for?

Inconel 625 is a nickel-based alloy used in many industries, including :

➪ Aerospace

➪ Nuclear

➪ Marine

➪ Chemical processing

➪ Automobile

➪ Paper

➪ Wire rope for mooring cables,

➪ Propeller blades for motor patrol gunboats,

➪ Submarine auxiliary propulsion motors,

➪ Submarine quick- disconnect fittings,

➪ Exhaust ducts for Navy utility boats,

You can get an offer for products in below material forms:

-Pipe and Tube (EN 10216-5, ASTM A213, ASTM A249, A312, A790,)

-Forged Fitting and Flange (ASTM A182 , ASTM A105,ASTM B564 )

-Butt Weld Fittings (ASTM A234, ASTM A403,ASTM A815)

-Round bar , Billet (ASTM A276, ASTM A479)

- Plate, Sheet, Strip(ASTM A240, EN 10028-7, A480)

-Bolting, Nuts（ASTM A193, A194, A320）

Inconel 625 Pipe Exported Countries

We Export Inconel 625 Pipe to Saudi Arabia, United Arab Emirates, Qatar, Bahrain, Oman, Kuwait, Turkey, Egypt, Yemen , Syria, Jordan, Cyprus, Singapore, Malaysia, Indonesia, Thailand, Vietnam, South Korea, Japan, Sri Lanka, Maldives, Bangladesh, Cambodia, Argentina, Bolivia, Brazil, Venezuela, Colombia, Ecuador, Guyana, Paraguay, Uruguay, United States Of America, Canada, Mexico, Panama, Jamaica, Bahamas, Denmark, Norway, Germany, France,Italy, United Kingdom, Spain, Belgium, Greece, Czech Republic, Portugal, Hungary, Albania, Austria, Finland, Ireland, Croatia, Malta, Nigeria, Algeria, Angola, South Africa, Libya, Egypt, Sudan,  Europe, Africa, Asia, North America, South America, Middle East.etc