Frequently Asked Questions about Inconel 600/601/625 Pipes

Inconel 600, 601, and 625 alloy tubes are high-performance nickel-chromium alloys used in extreme temperatures and corrosive environments, with varying compositions to meet specific strength requirements: 600 alloy tubes offer excellent strength and resistance to stress corrosion cracking (suitable for temperatures from cryogenic to 2000°F); 601 seamless tubes, with added aluminum, provide superior oxidation resistance; while 625 alloy tubes (containing molybdenum/niobium) offer outstanding strength and corrosion resistance in very harsh high-temperature chemical/marine environments, but they are expensive and difficult to process. The FAQ covers their unique corrosion and heat resistance properties, application areas (aerospace, chemical, oil and gas), high cost, and processing challenges.

What is the maximum operating temperature of Inconel 625?

Inconel 625 alloy is a non-magnetic, corrosion-resistant, and oxidation-resistant nickel-based alloy. It exhibits excellent strength and toughness over a wide temperature range, from cryogenic temperatures to 2000°F (1093°C), primarily due to the solid-solution strengthening effect of refractory metals niobium and molybdenum in the nickel-chromium matrix.

Gnee Steel is currently dedicated to manufacturing and supplying high-quality Inconel 600/601/625 pipes and tubes. These grades of pipes and tubes are meticulously manufactured using high-quality alloy materials, significantly enhancing product strength and quality. As a customer-centric company, we offer our clients a wide range of sizes, end forms, specifications, standards, types, lengths, and shapes. Our products are designed in strict accordance with various international product quality standards, such as ASME, ASTM, and API. Furthermore, we can also provide products according to customers' customized specifications and standards.

Equivalent Grades of Inconel 600/ 601/ 625 Pipe

STANDARD	UNS	WERKSTOFF NR.	AFNOR	GOST	OR	BS	JIS	EN
Inconel 600	N06600	2.4816	NC15FE11M	МНЖМц 28-2,5-1,5	ЭИ868	NA 13	NCF 600	NiCr15Fe
Inconel 601	N06601	2.4851	NC23FeA	XH60BT	ЭИ868	NA 49	NCF 601	NiCr23Fe
Inconel 625	N06625	2.4856	NC22DNB4M	ХН75МБТЮ	ЭИ602	NA 21	NCF 625	NiCr22Mo9Nb

Chemical Composition of Inconel 600/ 601/ 625 Tube

Grade

600

72.0 min

6.0 - 10.0

0.15 max

1.0 max

0.5 max

14.0 - 17.0

0.015 max

601

58.0 – 63.0

Balance

0.10 max

1.0 max

0.50 max

1.0 max

21.0 – 25.0

0.015 max

8.0-10.0

1.0 – 1.7

625

58.0 max

5.0 max

0.10 max

0.50 max

20.0 - 23.0

0.015 max

8.0 - 10.0

1.0 max

0.40 max

3.15 - 4.15

Mechanical Properties of Inconel 600/ 601/ 625 Pipe

Grade	Density	Melting Point	Tensile Strength	Yield Strength (0.2%Offset)	Elongation
600	8.47 g/cm3	1413 °C (2580 °F)	Psi – 95,000 , MPa – 655	Psi – 45,000 , MPa – 310	40 %
601	8.1 g/cm3	1411 °C (2571 °F)	Psi – 80,000 , MPa – 550	Psi – 30,000 , MPa – 205	30 %
625	8.4 g/cm3	1350 °C (2460 °F)	Psi – 1,35,000 , MPa – 930	Psi – 75,000 , MPa – 517	42.5 %

Frequently Asked Questions about Inconel 600/601/625 Pipes/Tubing

What are the main differences between Inconel 600, 601, and 625 pipes?
Inconel 600 pipes are primarily composed of a nickel-chromium alloy and have good oxidation resistance. Inconel 601 pipes have added titanium, improving oxidation resistance at high temperatures, while Inconel 625 pipes contain molybdenum, enhancing corrosion resistance.

What are the applications of these alloy pipes?
Inconel 600 pipes are used in heat exchangers and chemical processing. Inconel 601 seamless pipes are used in furnaces and gas turbines. Inconel 625 round pipes are ideal for marine and chemical industries due to their excellent corrosion resistance.

How do these alloys perform at high temperatures?
All three alloys perform well at high temperatures, with Inconel 601 pipes exhibiting the best oxidation resistance, making them suitable for continuous high-temperature environments.

How is the corrosion resistance of these alloys?
Inconel 600 pipes have good corrosion resistance to many corrosive environments. Inconel 601 pipes have higher oxidation resistance, while Inconel 625 pipes perform excellently in both reducing and oxidizing environments.

Can these alloys be welded?
Yes, all three alloys can be welded using various methods. Inconel 625 pipes are particularly known for their excellent weldability.

What are the common forms available?
Inconel 600, 601, and 625 are commonly supplied in the form of pipes, tubes, plates, and bars.

How do their costs compare?
Generally, Inconel 625 pipes are the most expensive due to their complex composition, followed by Inconel 601 pipes, and then Inconel 600 pipes.

Why Choose Gnee as Your Nickel-Based Alloy Supplier

✅ Over 18 years of export experience, products sold to more than 80 countries

✅ Certified by ISO, SGS, and BV

✅ Global inventory of Inconel, Hastelloy, Incoloy, and Monel alloy tubing, plates, and bars

✅ Custom processing services available – including cutting, polishing, CNC machining, and packaging

✅ Fast delivery within 7-15 days, supported by global logistics partners

📦 Packaging and Shipping

All stainless steel products are packaged using the following methods:

Wooden pallets or crates

Moisture-proof packaging

Labels with furnace number, standard, and size labels

Shipped worldwide by sea, air, or express