FLANGES
FLANGES
Flange Facing Types
Raised Face (RF): Most common; improves sealing with gaskets.
Flat Face (FF): Used with cast iron or low-pressure service.
Ring-Type Joint (RTJ): Metal-to-metal seal, ideal for high-pressure/high-temperature.
Tongue & Groove (T&G): Prevents gasket displacement.
Male & Female (M&F): Ensures gasket alignment.
Flange Dimensions & Standards
ASME B16.5: Covers sizes DN 15–DN 600 (½"–24").
ASME B16.47: Large diameter flanges DN 650–DN 2500 (26"–100").
API 6A / API 17D: Specialized for wellhead and subsea.
ISO 7005: International standard dimensions.
Material Selection
Carbon Steel (A105, A350 LF2): General service, moderate pressure.
Stainless Steel (304, 316L): Corrosion resistance, sour service.
Alloy Steel (F11, F22, F91): High-temperature refinery service.
Duplex/Super Duplex (2205, 2507): Offshore seawater resistance.
Nickel Alloys (Inconel, Monel): Extreme corrosion/temperature environments.
Pressure Classes
ASME: 150, 300, 600, 900, 1500, 2500.
API: 2000, 3000, 5000, 10000, 15000 psi.
Oil & gas pipelines often require Class 600–2500, while wellhead/subsea flanges go up to API 15000
FLANGE INSULATION KIT
A flange insulation kit (also called a flange isolation kit) is a set of non-conductive components installed between two flanges to electrically isolate the joint while maintaining sealing integrity.
A Flange Insulation Kit (FIK) is a sealing and isolation solution designed to electrically isolate two mating flanges while maintaining a reliable seal.
It is primarily used to prevent galvanic corrosion, control stray current, and enhance the effectiveness of cathodic protection systems in piping networks. Installed between flanged joints, the insulation kit creates a non-conductive barrier that blocks the flow of electrical current while still allowing the pipeline to operate safely under pressure and temperature conditions. This helps extend the service life of pipelines, valves, and connected equipment by minimizing corrosion-related damage.
Components:
Insulating Gasket – Provides sealing and electrical isolation between flange faces
Insulating Sleeves - Prevent metal-to-metal contact between bolts and flange holes
Insulating Washers - Electrically isolate the bolt head and nut from the flange
Steel Backing Washers – Provide mechanical strength and load distribution
Material Options:
G10/ G11 (epoxy glass laminate) for high strength and excellent insulation
Phenolic for general-purpose applications
PTFE for superior chemical resistance
GRE / Mylar sleeves and washers for enhanced durability
Available Standards & Sizes:
ASME / ANSI flange classes (150# to 2500#)
API and other international flange standards
All standard pipe sizes, with custom configurations available upon request