China Incoloy 800H Forging Supplier

As a dedicated supplier in the nickel alloy forged pipe fittings, we've spent years navigating the intricacies of high-performance materials like Incoloy 800H.

800H alloy, designated as UNS N08810, is a controlled-carbon variant of Incoloy 800, optimized with higher carbon content and aluminum-titanium additions for superior creep and rupture strength at temperatures above 1100°F (600°C). It excels in resisting oxidation, carburization, and sulfidation, making it a go-to choice for demanding environments.

Adhering to ASME B16.11, which governs socket-weld and threaded forged fittings, ensures these components meet stringent pressure ratings, dimensions, tolerances, and material standards.

In this blog post, I'll delve into the manufacturing process, detailed classifications of fittings, key applications, and comprehensive specification tables for Incoloy 800H forged fittings, drawing on industry standards for precision and reliability.

Manufacturing high-integrity Incoloy 800H forgings is a multi-stage process that demands strict control at every step to achieve the desired metallurgical structure and mechanical properties.

Incoloy 800H Forged Pipe Fittings Manufacturing Process

Step 1: Advanced Melting and Ingot Production: To achieve a high-purity, homogeneous ingot with low levels of impurities and gases, a double-melting process is typically employed.

This often involves Vacuum Induction Melting to create an electrode, followed by Electroslag Remelting. This process refines the grain structure and ensures precise control over the chemical composition, including the critical Ti/C ratio.

Step 2: Controlled Heating and Thermo-Mechanical Forging: The ingot is heated to a specific forging temperature under controlled conditions to prevent cracking and ensure uniform heat penetration.

The actual forging, often using processes like free forging or die forging, is conducted within a narrow thermal working window. Techniques like "two-upset and two-draw" with a total forging ratio greater than 6 are used to thoroughly break down the cast ingot structure, refine the grain, and optimize the microstructure for strength and density.

Step 3: Solution Annealing Heat Treatment: After forging, the component undergoes a solution annealing heat treatment followed by rapid quenching. This process dissolves secondary carbides back into the austenitic matrix, producing a homogeneous, single-phase structure. For Incoloy 800H, a coarser grain size is often targeted to optimize creep rupture strength.

Step 4: Machining and Quality Verification: The forgings are precision-machined to the final dimensions specified in ASME B16.11. Each fitting undergoes rigorous testing, including ultrasonic inspection for internal defects, liquid penetrant examination for surface flaws, and comprehensive mechanical and chemical analysis to confirm compliance with standards like ASTM B564.

ASME B16.11 classifies forged fittings by pressure class and end connection. Below are the primary types available in Incoloy 800H.

Fitting Type	Primary Function	Design Variants	Critical Dimensions (Examples for 3000 & 6000 lbs)
90° & 45° Elbows	Changes direction of flow.	90° & 45°; SW & Threaded.	C-to-End (3000 lbs): 1/2"=15.5mm, 2"=38mm. C-to-End (6000 lbs): 1/2"=19mm, 2"=41mm.
Tees (Equal & Reducing)	Creates a 90° branch from a main run.	Equal (all outlets same size); Reducing (branch size smaller).	C-to-End (3000 lbs): 1/2"=15.5mm, 1-1/2"=32mm. C-to-End (6000 lbs): 1/2"=19mm, 1-1/2"=38mm.
Couplings	Connects two pipes.	Full Coupling (connects two pipes); Half Coupling (branch connection).	Socket Bore (3000 lbs): ~NPS + 1/16". Length per ASME B16.11 tables.
Reducers	Connects pipes of different sizes.	Concentric (aligned centers); Eccentric (maintains BOP or TOP).	Major dimensions: Outside diameters of both ends, overall length.
Caps	Seals the end of a pipe.	Socket Weld & Threaded.	Socket Depth/Thread Length: Per class and NPS. Overall height as per standard.
Unions	Allows for easy disconnection of piping.	Three-piece design (nut, female, male ends).	Key specs: Overall length, seat angle, nut dimensions.
Crosses	Creates a four-way connection.	Equal (all outlets same); Reducing (one or more outlets different).	C-to-End: Similar to tees but in four directions. Used cautiously in high-stress services.

Incoloy 800H forged fittings are manufactured to meet strict international standards. Their chemical and mechanical properties are outlined below:

Chemical Composition (Typical, wt%)

Element	Ni	Cr	Fe	C	Mn	Si	Cu	Al	Ti	S
Content	30.0-35.0	19.0-23.0	≥39.5	0.05-0.10	≤1.50	≤1.00	≤0.75	0.15-0.60	0.15-0.60	≤0.015

Mechanical Properties (Typical at Room Temperature)

Property	Tensile Strength	Yield Strength (0.2% Offset)	Elongation	Density	Melting Point
Value	≥520 MPa	≥205 MPa	≥30%	7.94 g/cm³	~1385 °C

International Equivalent Grades

Standard	UNS	Werkstoff Nr.	EN	JIS	AFNOR
Incoloy 800H	N08810	1.4958 / 1.4876	X5NiCrAlTi31-20	NCF 800H	Z8NC33-21

Incoloy 800H forged fittings are deployed in environments demanding resilience to extreme heat and corrosion.

Incoloy 800H Forged Pipe Fitting Applications

In hydrocarbon processing, they handle cracking units and reformers, resisting carburization at elevated temperatures.

Heat-treat furnaces utilize them for baskets, trays, and fixtures, where the alloy's creep strength prevents deformation over prolonged cycles.

Power generation applications include superheater and reheater tubing in boilers, benefiting from oxidation resistance up to 1800°F (980°C).

In chemical and petrochemical plants, they excel in heat exchangers and condensers exposed to chloride stress-corrosion, while nuclear facilities leverage their stability in nitriding atmospheres.

Overall, these fittings ensure system integrity in sulfuric acid production, ethylene pyrolysis, and other aggressive media, reducing downtime and maintenance costs.