ASTM A105 Weld Neck flange with SS316L Welding Overlay

ASTM A105 Weld Neck Flange with SS316L Welding Overlay

We are a reliable manufacturer and supplier of ASTM A105 Carbon Steel Flanges with Weld Overlay (Clad Flanges).
These flanges combine the strength of carbon steel with the corrosion resistance of stainless steel or nickel alloys, making them ideal for oil, gas, and chemical processing industries.

ASTM A105 weld neck flanges with ss 316L stainless steel welding overlay are specially engineered components combining carbon steel strength with corrosion-resistant stainless steel surfaces. These flanges are ideal for high-pressure, high-temperature, and corrosive environments such as oil & gas, chemical processing, refineries, and offshore industries.

A weld overlay flange is a flange made from a base material—typically carbon steel or low alloy steel—onto which a layer of corrosion-resistant alloy (CRA), such as stainless steel, Inconel, or Monel, is welded onto the sealing surface. This technique allows manufacturers to combine the mechanical strength of a cheaper base metal with the corrosion resistance of a high-performance alloy, achieving both cost efficiency and performance.

What Is a Weld Overlay Flange?

A weld overlay flange is produced by applying a layer of alloy material (such as SS316L, Inconel 625, Alloy 825, etc.) onto the wetted surfaces of a flange made from carbon steel like ASTM A105, A350 LF2, or A182 F11. This cladding is typically applied using GTAW (TIG), SMAW (stick), or SAW (submerged arc welding) methods.

ASTM A105 316L Welding overlay flanges specification

Base Material: ASTM A105/A105N (Carbon Steel, forged)
Overlay Material: SS316L (Low-Carbon Austenitic Stainless Steel)
Flange Type: Weld Neck (WN)
Face:Ring joint or raise face
Standards: ASME B16.5 / ASME B16.47 / MSS-SP-44
Pressure Ratings: Class 150 – 2500
Size Range: ½” – 48” (DN15 – DN1200)

Why Use SS316L Overlay on A105?

The welding overlay (cladding) of SS316L on the wetted surface of the A105 flange enhances its resistance to corrosion, pitting, and crevice attack from chemicals, seawater, acids, and chlorides — while the A105 core provides excellent mechanical strength and cost efficiency.

316L Stainless Steel Features:

Low carbon = better weldability and intergranular corrosion resistance
Resistant to chloride corrosion and acidic environments
Excellent durability in aggressive media (acetic, sulfuric acids)

A105 316L Welding overlay flanges Manufacturing Process

Flange Forging (A105)
Machining of base shape
Welding Overlay (cladding) using GTAW/SMAW/SAW process with SS316L filler metal
Post-weld Heat Treatment (if required)
Final machining to dimensions (ASME/DIN/JIS)
Inspection & Testing (Visual, PMI, UT, Hardness)

ASTM A105 with SS316L Welding Overlay flanges

A105 316L Welding overlay flanges Specifications Summary

Parameter	Value
Flange Material	ASTM A105 (Forged Carbon Steel)
Cladding Material	SS316L (UNS S31603)
Overlay Thickness	Typically 3mm – 5mm thickness overlay
Standards	ASME B16.5 / B16.47 / MSS-SP-44
Testing	PMI, UT, PT, Hydro, Dimensional
Documentation	EN 10204 3.1 / 3.2 MTC, NACE MR0175
Application Standard	NORSOK, Shell DEP, Total GS, Aramco

Welding overlay flanges Applications

Offshore oil platforms & FPSOs
Sour gas (H₂S) systems (NACE MR0175)
Petrochemical and refinery piping
Desalination and seawater cooling lines
Chemical reactors and pressure vessels

Common flange body and Cladding material

Base Material	Cladding Material	Application Example
ASTM A105	SS316L	Oil & gas, seawater lines
ASTM A182 F11	Inconel 625	Sour service (H₂S), offshore
ASTM A350 LF2	Alloy 825	Chemical processing
ASTM A516 Gr.70	SS317L	Desalination, pulp & paper

Weld Overlay Flange Manufacturer & Exporter

As a leading manufacturer of weld overlay flanges, we offer:

In-house overlay welding (GTAW, SAW, etc.)
Full NDT and material traceability
Short delivery times with global export packing

Cladding Flange Manufacturing Process Flow

I. Pre-Production Preparation

Base Flange Preparation
- Material Selection: Carbon steel (e.g., SA350 LF2, A105) or low-alloy steel (e.g., SA182 F11/F22).
- Blank Machining:
  - Cut/forge ring blanks from round bars or plates.
  - Rough-machine overall dimensions (OD, ID, thickness, bolt hole circle).
  - Allow 3–5+ mm machining allowance on cladding surfaces.
- Groove Preparation:
  - Machine grooves on sealing faces:
    - Flat Surface: Simple but high dilution.
    - Recessed Groove (U/Rectangular): Preferred for lower dilution.
- Cleaning: Degrease + mechanically grind (stainless brush) to bare metal.
Cladding Material Prep
- Material: Austenitic SS (ER308L/309L/316L), Ni-alloy (ERNiCrMo-3), or Co-alloy (Stellite 6).
- Form: Wire (MIG/TIG/SAW), Strip (SAW/ESW), or Electrode (SMAW).
- Preheat: Dry electrodes per AWS/EN standards.
Equipment Setup
- Rotator/turning rolls for uniform deposition.
- Welding power source (SAW/GTAW/GMAW/SMAW).
- Preheating tools (if required per WPS).
- Temperature guns, fume extraction.

II. Welding Procedure Qualification (WPQ)

WPS Qualification: Qualify per ASME Sec. IX or ISO 15614.
Essential Variables:
- Base/clad material grades.
- Preheat/interpass temp.
- Heat input (kJ/mm).
- Number of layers.

III. Cladding Process

Preheating (If Applicable)
- Preheat base to 100–200°C (material-dependent).
- Monitor with temp sticks/IR gun.
Buttering Layer (Critical for dissimilar metals)
- Deposit 1–2 transition layers (e.g., ER309L on carbon steel).
- Control dilution < 10%.
Cladding Layer Deposition
- Process Selection:MethodApplicationSAW (Strip)High-speed, flat surfacesGTAW (Wire)Precision, complex geometriesSMAWRepairs/small batches
- Key Controls:
  - Interpass temp ≤ 150°C (SS/Ni-alloys).
  - Layer thickness: 3–4 mm/layer.
  - Overlap: 30–50% for strip cladding.
Post-Weld Cooling
- Slow cooling (cover with thermal blanket) for crack-sensitive alloys.

IV. Post-Cladding Treatment

Stress Relief (If Required)
- PWHT per base material code (e.g., ASME B31.3).
- Caution: Avoid sensitization of SS (e.g., 870°C max for 316L).
Machining
- Finish-machine sealing face to Ra ≤ 3.2 μm.
- Verify clad thickness ≥ design min. (e.g., 3 mm).

V. Inspection & Testing

NDE:
- VT: Per ASME B31.3 – no cracks, undercut.
- PT/MT: Surface defects on clad/base.
- UT: Bond integrity (interface defects).
Destructive Testing (Sample Coupons):
- Hardness survey (clad, HAZ, base).
- Chemical analysis (PMI) of clad layer.
- Corrosion test (ASTM G48/A262).

VI. Documentation

MTRs for base/clad materials.
WPS/PQR records.
NDE reports (PT/UT/RT).
Final dimensional report.

Example Order Information

Product: ASTM A105 + SS316L Weld Neck Flange
Size: 12” Class 600 RF
Standard: ASME B16.5
Overlay Thickness: 3 mm
Welding Process: GTAW + SAW
Testing: UT + PT + Chemical Analysis
Certification: EN 10204 3.1 + NACE MR0175

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