Description

Stainless Steel Cast and Machined Flanges

Stainless Steel Fittings India is a leading manufacturer and exporter of Stainless Steel Cast and Machined Flanges. Our flanges are precision-cast using shell molding, sand casting, and investment casting processes, then CNC machined to exact dimensional tolerances for seamless piping system assembly across oil & gas, chemical, marine, and industrial sectors.

Types of Stainless Steel Cast Flanges

• Weld Neck Flanges (WNF) – High-pressure applications with smooth bore transition
• Slip-On Flanges (SOF) – Easy alignment and installation
• Blind Flanges (BLF) – Closing pipe ends under high pressure
• Socket Weld Flanges (SWF) – Small-diameter high-pressure piping
• Threaded Flanges (TF) – No welding required; screwed connections
• Lap Joint Flanges (LJF) – Used with stub ends for easy alignment
• Orifice Flanges – Flow measurement applications
• Long Weld Neck Flanges – Nozzle extensions and column connections
• Spectacle Blind Flanges – Isolation and flow control

Material Grades Available

• SS 304 / SS 304L (ASTM A182 F304/F304L)
• SS 316 / SS 316L (ASTM A182 F316/F316L)
• SS 321 (ASTM A182 F321)
• SS 347 (ASTM A182 F347)
• Duplex SS 2205 (ASTM A182 F51)
• Super Duplex SS 2507 (ASTM A182 F53)
• SS 904L

Casting Processes for Stainless Steel Flanges

• Shell Molding: Precision small-to-medium flanges with excellent surface finish Ra 3.2–6.3 µm
• Sand Casting: Cost-effective for large flanges and special configurations
• Investment Casting: Complex geometry flanges requiring near-net shape and minimal machining

Dimensional Standards

• ASME B16.5 (1/2″ to 24″ NPS)
• ASME B16.47 Series A & B (26″ to 60″ NPS)
• ASME B16.48 – Line Blanks
• MSS SP-44 – Steel Pipeline Flanges
• EN 1092-1 (PN6 to PN400)
• DIN 2631 to DIN 2638
• JIS B 2220
• BS 4504

Pressure Ratings

Class 150, 300, 400, 600, 900, 1500, and 2500 per ASME B16.5. PN 6, 10, 16, 25, 40, 63, 100, 160, 250, and 400 per EN/DIN standards.

Surface Finishing Options

• Raised Face (RF)
• Flat Face (FF)
• Ring Type Joint (RTJ)
• Tongue and Groove (T&G)
• Male and Female (M&F)

Applications

• Oil and gas pipelines and refineries
• Petrochemical and chemical processing plants
• Marine and offshore platforms
• Water treatment and desalination plants
• Power generation and steam systems
• Pharmaceutical and food processing
• Pulp and paper industry

Frequently Asked Questions (FAQs)

Q1: What is the difference between a cast flange and a forged flange?

Cast flanges are produced by pouring molten metal into molds, enabling complex shapes and large sizes at lower tooling cost. Forged flanges are worked mechanically to align grain structure, resulting in higher tensile strength and toughness. Cast flanges per ASTM A351/A743 are suitable for most pressure and temperature applications, while forged flanges per ASTM A182 are preferred for high-pressure, high-temperature critical service.

Q2: What size range do you manufacture for stainless steel cast flanges?

We manufacture stainless steel cast flanges from 1/2″ NPS to 48″ NPS (DN15 to DN1200). For sizes above 24″, sand casting is the primary process. Custom sizes outside standard ranges are also available per customer drawings.

Q3: Can you cast flanges with special bore sizes or non-standard configurations?

Yes. We specialize in non-standard and custom cast flanges including reducing flanges, expanding flanges, anchor flanges, and flanges with special bore profiles. All we require is a detailed drawing or 3D model to proceed with pattern development.

Q4: What is the price of stainless steel cast and machined flanges?

The base price for stainless steel cast and machined flanges is USD 11.30 per kilogram. Pricing varies based on grade, size, pressure class, surface finish, and quantity. Contact us with your specifications for a detailed quotation.

Q5: Do you offer third-party inspection for cast flanges?

Yes. We welcome third-party inspection from agencies such as Lloyd’s Register, Bureau Veritas, TUV, SGS, Intertek, and others. We provide full documentation including material test reports (MTR), heat treatment records, dimensional inspection reports, and NDT certificates.

Q6: What NDT testing is performed on your cast flanges?

Standard NDT includes visual inspection and dimensional checking. Optional tests available include Liquid Penetrant Testing (LPT/DPT), Radiographic Testing (RT), Ultrasonic Testing (UT), Magnetic Particle Inspection (MPI for ferritic grades), and hydrostatic pressure testing. We follow ASTM, ASME, and EN testing standards.

Q7: Do your flanges come with material traceability?

Yes. All our stainless steel cast flanges are supplied with EN 10204 3.1 or 3.2 material test certificates. Each casting is heat-numbered and traceable back to the melt. We maintain full traceability records for a minimum of 10 years.

Q8: Can you supply flanges in Duplex or Super Duplex stainless steel?

Yes. We cast and machine flanges in Duplex SS 2205 (UNS S31803/S32205) and Super Duplex SS 2507 (UNS S32750) for applications requiring higher strength and superior pitting resistance. These are especially suitable for offshore, subsea, and chloride-rich environments.

Q9: What is the typical lead time for cast and machined flanges?

Standard flanges in common grades (SS 304, SS 316) are available ex-stock or with 2–3 weeks lead time. Custom cast flanges require 4–8 weeks depending on size, complexity, and quantity. Tooling for new patterns requires an additional 3–5 weeks for the first order.

Q10: Are your cast flanges suitable for cryogenic service?

Yes. SS 304L and SS 316L castings are suitable for cryogenic service down to -196°C (liquid nitrogen temperature). Impact testing per ASTM A352 LCB/LCC standards is available. Please specify operating temperature range when requesting quotations.

Q11: What packaging do you use for exporting flanges?

Flanges are cleaned, passivated, and capped on face and bore. They are then individually wrapped, packed in wooden boxes or on pallets, and secured for sea freight or air freight as required. We comply with ISPM 15 regulations for wooden packaging for international shipments.

Q12: Do you manufacture flanges per customer drawings and specifications?

Absolutely. We are an OEM manufacturer and accept customer-supplied drawings in DXF, DWG, PDF, STEP, or IGES formats. Our engineering team reviews drawings for castability and suggests optimizations before pattern development. NDA agreements are signed to protect customer intellectual property.