Special alloy flanges are high-performance pipeline connectors designed specifically for extreme working conditions, with excellent characteristics such as high temperature resistance, corrosion resistance, and creep resistance. They are widely used in high-end fields such as nuclear power, aerospace, deep-sea oil and gas, and supercritical chemical engineering. The main materials are:Hastelloy, Monel, Inconel, and specialty metals.

Product Features‌

Extreme environmental adaptability: using special alloy materials such as nickel based, cobalt based, or titanium alloys (such as Inconel 600、Hastelloy C-276、Ti6Al4V）， It can operate stably in high temperatures above 600 ℃ or strong acid/strong alkali/chloride ion environments.

High strength and toughness: The mechanical properties are improved through processes such as solid solution strengthening and aging treatment, and the tensile strength can reach 700-1000 MPa or more, meeting the requirements of high-pressure systems.

Excellent corrosion resistance: It exhibits extremely low corrosion rates in media containing salt spray, sulfides, nitric acid, hydrofluoric acid, etc. Some materials have more than ten times better resistance to chloride ion stress corrosion than stainless steel 316L.

Precision manufacturing process: using vacuum induction melting+electric slag remelting+hot forging forming+CNC precision machining to ensure material purity and dimensional accuracy.

High degree of customization: commonly used for non-standard equipment interfaces, supporting graphic processing, special bolt hole distribution, and composite sealing structure design.

According to the sealing level requirements of the working conditions, various high reliability sealing surfaces can be provided:

Ring Joint (RJ): Using octagonal or elliptical metal ring pads to achieve line contact sealing, suitable for high temperature and high pressure (such as Class2500) systems.

RF (Raised Face): Used in conjunction with wound gaskets, it is the mainstream choice for medium to high voltage systems.

Tongue and Groove (TG): prevents the gasket from being flushed out by the medium, suitable for flammable, explosive, or highly toxic media.

Male Female Face (MFM): Accurate positioning, suitable for frequent disassembly and maintenance scenarios.

Flat Face (FF): Used for low-pressure, non critical connections such as auxiliary pipelines.

Special alloy flanges must comply with high international and industry standards to ensure safety and interchangeability

International standard:

ASME B16.5/B16.47: American standard system, covering Class 150 to Class 2500.

EN 1092-1 (PN): European standard applicable to PN6 to PN400.

Material and Performance Standards:

ASTM B564/ASME SB564: Nickel alloy forging standard, applicable to Inconel 600, 625, etc.

ASTM F67/F136: Medical and Industrial Standards for Titanium and Titanium Alloys.

UNS N06600/N10276: Unified numbering system, specifying material composition and grade.

Chinese standards:

GB/T 2965-2007: Standard for Titanium Flanges.

HG/T 20592-2009: Chemical industry flange standard, supporting reference to special materials.

Dimensions‌

Nominal diameter (DN): DN10 to DN2000 (3/8 "to 78"), covering small diameter instrument pipes to large main process pipelines.

Outer diameter range: 75mm~2190mm, bolt hole center distance 50mm~2130mm.

Bolt configuration: 4-48 holes, hole diameter 11-30mm, thread specification M10-M27.

Flange thickness: 12-58mm, high-pressure or large-diameter flanges can be thickened to 100mm or more to enhance pressure bearing capacity.

Theoretical weight: 0.36kg~234.6kg (DN1800), depending on material density and structure (e.g. titanium alloy flange is about 40% lighter than carbon steel).

pressure rating‌

Class system (America): Class 150 to Class 2500, suitable for ultra-high pressure conditions (such as deep-sea oil extraction, nuclear reactor cooling circuits).

PN体系（欧洲/中国）‌：‌PN6 至 PN42.0‌（约 0.6～32 MPa），适用于中高压系统。

K单位（日标）‌：‌5K、10K、16K、20K‌，其中 ‌10K ≈ 1.0 MPa‌。

特殊等级‌：部分核电用法兰可达 ‌CL4500‌ 或更高，需单独设计验证。

选型提示‌：特种合金法兰成本高昂，建议仅在普通不锈钢无法满足工况时选用，并优先明确‌UNS编号‌与‌热处理状态‌（如固溶退火态）。