Introduction

Inconel 625 Plate (UNS N06625 / Alloy 625) is a nickel-chromium-molybdenum alloy with niobium (columbium) addition, conforming to ASTM B443 (plate, sheet, and strip), ASME SB443, AMS 5599, and AMS 5869. The molybdenum (8–10%) and niobium (3.15–4.15%) work together to stiffen the alloy matrix, providing high strength without the need for a strengthening heat treatment. This high temperature nickel alloy plate delivers excellent resistance to a wide range of severely corrosive environments and is especially resistant to pitting and crevice corrosion. The alloy maintains mechanical properties from cryogenic temperatures up to 1800°F (980°C), with good oxidation resistance and outstanding seawater resistant alloy performance. ASTM B443 specifies two conditions: Grade I (Annealed) – the default condition, and Grade II (Solution Annealed) – for enhanced high-temperature creep properties. This corrosion resistant nickel alloy plate is the preferred material for offshore platforms, oil and gas production, chemical processing, marine engineering, heat exchangers, pressure vessels, aerospace, nuclear industry, and FGD systems. Available in Inconel 625 plate, sheet, strip, and coil, in hot rolled and cold rolled forms, with custom size and precision cut options.

Specifications & Process Options

Applications

1. Offshore Platforms & Oil and Gas

• For offshore platforms, subsea production systems, and sour gas service per NACE MR0175, Inconel 625 plate for offshore provides exceptional resistance to seawater corrosion and chloride-induced stress corrosion cracking. The seawater resistant alloy is widely used in subsea flowline connectors, wellhead hangers, compact flanges, and clamp hubs.

• For oil and gas production equipment, wellhead and Christmas tree components, and production tubing, Alloy 625 plate withstands hydrogen sulfide and elementary sulfur at temperatures exceeding 150°C. This corrosion resistant Inconel 625 is specified for flare stacks on offshore platforms and hydrocarbon processing facilities.

• For pressure vessel applications in offshore environments, ASTM B443 Inconel 625 plate combines high strength with excellent resistance to pitting and crevice corrosion.

2. Chemical Processing & Heat Exchangers

• For chemical processing reactors, distillation columns, and reaction vessels, Inconel 625 plate for chemical processing resists a wide range of organic and mineral acids, with excellent resistance to pitting, crevice, and corrosion cracking.

• For heat exchangers, furnace hardware, and industrial tubing, Nickel Alloy 625 Plate provides high temperature strength and oxidation resistance up to 980°C.

• For spray bars, bubble caps, chimney liners, and production tubes for sour gases, Alloy 625 plate delivers the durability and performance required in aggressive chemical environments.

3. Marine Engineering & Aerospace

• For marine engineering applications, Inconel 625 plate for marine engineering offers virtual immunity to chloride‑induced stress corrosion cracking, with a high Pitting Resistance Equivalent Number (PREN) typically exceeding 45.

• For aerospace components requiring reliability under great stress and extreme temperatures, hot rolled Inconel 625 plate maintains strength from cryogenic temperatures up to 1800°F (980°C).

• For pollution‑control equipment, seawater systems, and nuclear reactors, UNS N06625 plate provides long‑term reliability in the most demanding environments.

4. Power Generation & FGD Systems

• For power generation equipment including gas turbine components and waste incineration plants, Inconel 625 plate for power generation offers excellent resistance to high‑temperature oxidation and thermal fatigue.

• For FGD systems, scrubber internals, and stack gas reheater components, ASTM B443 plate withstands low‑pH, high‑chloride environments with superior pitting resistance.

5. Pressure Vessels & Industrial Equipment

• For ASME‑coded pressure vessels in high‑temperature corrosive service, Inconel 625 plate for pressure vessel combines high tensile strength (827 MPa min) with excellent fabricability.

• For furnace hardware, heat shields, and industrial tubing, cold rolled Inconel 625 sheet provides stability during welding with scaling and oxidation resistance.

FAQ – Inconel 625 Plate

Q: What is the difference between Grade I and Grade II in ASTM B443?

A: Grade I (Annealed) is the standard condition for Inconel 625 plate, with tensile strength of 120 ksi (827 MPa) and yield strength of 60 ksi (414 MPa). It is the default delivery condition. Grade II (Solution Annealed) offers lower strength (100 ksi tensile, 40 ksi yield) but provides better creep properties at high temperatures. If your application requires operation at elevated temperatures, specify Grade II.

Q: What is the maximum operating temperature for Inconel 625 plate?

A: Inconel 625 plate operates effectively from cryogenic temperatures up to 1800°F (980°C). It maintains good oxidation resistance up to 980°C and offers excellent strength at temperatures up to 816°C. At higher temperatures, the alloy's strength is generally lower than other solid‑solution strengthened alloys.

Q: What industries commonly use ASTM B443 Inconel 625 plate?

A: Offshore platforms and oil and gas production (subsea flowlines, wellhead equipment, sour gas service per NACE MR0175), chemical processing (reactors, distillation columns, heat exchangers, spray bars), marine engineering (seawater systems, corrosion‑resistant components), aerospace (high‑temperature components), power generation (waste incineration, gas turbines), pollution‑control equipment (FGD scrubbers, stack gas systems), and nuclear reactors.

Q: What are the key ASTM standards for Inconel 625 plate?

A: ASTM B443 is the primary specification for Inconel 625 plate, sheet, strip, and coil. ASME SB443 is the ASME equivalent for pressure vessel applications. AMS 5599 covers sheet, strip, and plate for aerospace applications. AMS 5869 is also applicable. Related standards include ASTM B444 (seamless pipe and tube) and ASTM B446 (bar and rod).

We are a trusted Inconel 625 Plate Supplier and Alloy 625 Plate Manufacturer, China‑based, serving offshore contractors, chemical processors, heat exchanger fabricators, and aerospace manufacturers worldwide. All products comply with ASTM B443 / ASME SB443 with EN 10204 3.1 mill certificates, PMI verification, and dimensional inspection reports. We offer Inconel 625 hot rolled plate, cold rolled plate, sheet, strip, and coil in custom sizes, with precision cut, laser cut, and water jet cut services. Heavy thickness plates available up to 100mm. Contact us at info@monokj.com for size chart, pricing, or custom requirements.