ANSI B16.47 FLANGES

Super Industries
“Global Manufacturer of Heavy & Custom Engineered Fasteners for Oil & Gas, Power & EPC Contractors.”

1. Industry Context & System Relevance

Role of ANSI B16.47 Flanges in Large-Diameter Piping Systems

ANSI B16.47 Flanges are engineered for large-bore piping systems (NPS 26” to 60”) where pressure containment, structural stability, and maintainability are critical. These flanges are deployed in systems where welded joints alone are insufficient due to operational, inspection, or maintenance constraints.

Large-diameter pipelines operate under combined loading conditions:

• Internal pressure
• External mechanical loads
• Thermal expansion
• Environmental stressors

In such systems, flanged joints provide controlled disassembly capability, enabling inspection, maintenance, and component replacement without cutting or re-welding.

Primary Application Sectors

Oil & Gas Transmission Pipelines

Used in cross-country pipelines for crude oil, natural gas, and multiphase fluids where large diameters reduce frictional losses and improve flow efficiency.

Refineries

Installed in process units such as distillation columns, hydrocrackers, and storage transfer systems where periodic shutdown inspection is required.

Offshore Platforms

Applied in topside modules and subsea tie-ins where modular assembly and disassembly are essential due to logistical constraints.

Power Generation Plants

Used in cooling water systems, steam exhaust systems, and flue gas ducting involving large flow volumes.

Petrochemical Facilities

Installed in bulk fluid transfer lines handling hydrocarbons, chemicals, and gases under varying pressure and temperature conditions.

LNG Terminals

Used in cryogenic and regasification systems requiring dimensional stability and leak-tight performance.

Water Transmission Systems

Applied in municipal and industrial water pipelines, desalination plants, and flood control systems.

Why Large-Diameter Flanged Joints Are Preferred

1. Maintenance Accessibility

Flanged joints allow non-destructive disassembly, essential for:

• Internal inspection
• Gasket replacement
• Valve and equipment maintenance

2. Inspection-Critical Systems

Used in systems governed by:

• Periodic NDT inspection
• Regulatory compliance
• Shutdown-based maintenance schedules

3. High-Pressure Large Bore Pipelines

Ensure:

• Controlled gasket sealing
• Uniform load distribution
• Resistance to leakage under pressure fluctuations

4. Alignment Flexibility

Allow minor alignment corrections during installation, unlike welded joints which require precise fit-up.

2. Technical Definition

Definition of ANSI B16.47 Flanges

ANSI B16.47 Flanges are:

• Pressure-retaining flanged connections
• Designed for Nominal Pipe Size (NPS) 26” to 60”
• Governed by ASME B16.47 standard
• Applicable where ASME B16.5 dimensional limits are exceeded

They are used in conjunction with:

• Bolting systems (ASTM A193/A194)
• Gaskets (ASME B16.20 / B16.21)
• Large-diameter piping systems

Series Classification

ANSI B16.47 Flanges are divided into two dimensional series:

Series A (Derived from MSS SP-44)

Characteristics:

• Larger bolt circle diameter
• Higher number of bolts
• Larger bolt diameters
• Greater flange thickness
• Higher structural rigidity
• Increased weight

Engineering Implication:

• Suitable for high-stress, high-load applications
• Preferred in critical service pipelines

Series B (Derived from API 605)

Characteristics:

• Smaller bolt circle diameter
• Fewer bolts
• Smaller bolt sizes
• Reduced flange thickness
• Lower weight

Engineering Implication:

• Economical for moderate pressure systems
• Used where load conditions are less severe

Dimensional Differences: Series A vs Series B

Parameter	Series A	Series B
Bolt Circle Diameter	Larger	Smaller
Number of Bolts	Higher	Lower
Bolt Size	Larger	Smaller
Flange Thickness	Higher	Lower
Weight	Higher	Lower
Structural Strength	Higher	Moderate

Engineering Selection Consideration

Selection between Series A and Series B depends on:

• Design pressure
• External loading conditions
• Weight constraints
• Cost considerations
• Compatibility with existing systems

3. Engineering & Sealing Principle

Fundamental Sealing Mechanism

ANSI B16.47 Flanges achieve sealing through:

Bolt preload → gasket compression → sealing stress → leak prevention

Bolt Preload Mechanics

When bolts are tightened:

• Tensile force is induced in the bolt
• Compressive force is applied on the gasket
• Flange faces are drawn together

The preload must:

• Exceed internal pressure-induced separation force
• Maintain gasket compression under operating conditions

Gasket Compression Theory

Gasket sealing requires:

• Initial seating stress → to deform gasket surface
• Operating stress retention → to maintain seal under pressure and temperature

Key parameters:

• Gasket factor (m)
• Minimum seating stress (y)

Flange Face Contact Stress

Contact stress must be:

• Uniform across gasket surface
• Above minimum sealing stress
• Below material yield limits

Improper stress distribution leads to:

• Leakage paths
• Gasket failure
• Bolt relaxation

Leakage Prevention Mechanisms

Leak prevention depends on:

• Adequate bolt preload
• Proper gasket selection
• Controlled surface finish
• Flange rigidity

Facing Types

Raised Face (RF)

• Most commonly used
• Provides controlled gasket seating area
• Suitable for soft gaskets

Ring Type Joint (RTJ)

• Metal-to-metal sealing with ring gasket
• Used in:
  • High-pressure systems
  • High-temperature service
  • Critical hydrocarbon applications

Gasket Seating vs Operating Stress

Condition	Requirement
Initial Installation	High seating stress required
Operating Condition	Stress must remain above leakage threshold

Loss of stress occurs due to:

• Thermal expansion
• Creep relaxation
• Bolt relaxation

Bolt Stress vs Internal Pressure Interaction

Internal pressure generates:

• Axial separation force
• Radial expansion force

Bolt preload must counteract:

• Hydrostatic end force
• Gasket blowout tendency

Flange Rotation & Deflection

Under load:

• Flanges tend to rotate outward
• Outer edge experiences higher stress
• Inner edge may lose contact pressure

Design must ensure:

• Controlled rotation
• Adequate stiffness
• Uniform gasket compression

4. Pressure & Load Engineering

Pressure Classes in ANSI B16.47 Flanges

• Class 75
• Class 150
• Class 300
• Class 400
• Class 600
• Class 900

These classes define:

• Maximum allowable pressure
• Temperature-pressure relationship

Internal Pressure Loading

Internal pressure produces:

• Axial force trying to separate flanges
• Hoop stress in pipe
• Radial stress on flange faces

External Loads

Pipe Weight

Acts as bending load on flange joint

Thermal Expansion

Causes:

• Axial displacement
• Additional stress on bolts and flange

Wind & Seismic Forces

Relevant for:

• Above-ground pipelines
• Offshore structures

Flange Design Stress Limits

Controlled by:

• Material yield strength
• Allowable stress (ASME Section II)
• Design safety factors

Gasket Stress Retention

Critical for long-term sealing:

• Must maintain compression over time
• Affected by:
  • Temperature
  • Pressure cycles
  • Material creep

Fatigue Considerations

Cyclic loading leads to:

• Bolt fatigue
• Flange cracking
• Gasket degradation

Applicable in:

• Pulsating flow systems
• Compressor discharge lines
• Offshore installations

Dimensional & Design Logic

Key Dimensional Parameters

Bolt Circle Diameter (BCD)

Defines bolt placement and load distribution

Number of Bolts

Determines:

• Load sharing
• Gasket compression uniformity

Bolt Size & Length

Must satisfy:

• Tensile strength requirements
• Engagement length criteria

Flange Thickness

Controls:

• Structural rigidity
• Resistance to bending
• Load distribution

Hub Dimensions (For Weld Neck Flanges)

Provide:

• Stress transition between pipe and flange
• Reduction in stress concentration

Facing Types

• Raised Face (RF)
• Flat Face (FF)
• Ring Type Joint (RTJ)

Dimensional Control Parameters

Flatness Tolerance

Ensures uniform gasket seating

Parallelism

Prevents uneven bolt loading

Concentricity

Ensures alignment with pipe axis

Surface Roughness (Ra Values)

Typical values:

• RF: 3.2 – 6.3 µm
• RTJ grooves: precision machined as per standard

Engineering Importance of Dimensional Control

Deviation leads to:

• Uneven gasket compression
• Bolt overstressing
• Leakage risk

5. Applicable Standards

Primary Governing Standard — ASME B16.47

ANSI B16.47 Flanges are designed, manufactured, and inspected in accordance with:

• ASME B16.47
  • Covers large-diameter flanges (NPS 26” to 60”)
  • Defines:
    • Dimensions
    • Pressure-temperature ratings
    • Tolerances
    • Marking requirements
  • Divided into:
    • Series A (MSS SP-44 origin)
    • Series B (API 605 origin)

This standard ensures interchangeability, dimensional consistency, and pressure integrity across global EPC projects.

Boundary Standard — ASME B16.5

• Covers flanges up to NPS 24”
• Used as a design and selection reference boundary
• Ensures continuity when transitioning from smaller to large-diameter piping systems

Series-Origin Standards

MSS SP-44

• Basis for Series A flanges
• Originally developed for:
  • High-pressure transmission pipelines
• Emphasizes:
  • Increased bolt count
  • Higher structural rigidity

API 605

• Basis for Series B flanges
• Designed for:
  • Refinery and process piping systems
• Focus on:
  • Reduced weight
  • Dimensional compatibility with legacy systems

Material Standards (ASTM)

Material selection for ANSI B16.47 Flanges is governed by ASTM specifications:

Carbon Steel

• ASTM A105 — Forged carbon steel for ambient and elevated temperature
• ASTM A350 LF2 — Low-temperature carbon steel with impact toughness

Stainless Steel

• ASTM A182 F304 — General corrosion resistance
• ASTM A182 F316 — Enhanced resistance to chlorides and chemicals

Alloy Steel

• ASTM A182 F11 — Chromium-molybdenum alloy for moderate temperature
• ASTM A182 F22 — Higher temperature and pressure capability

Duplex / Super Duplex

• High strength + corrosion resistance
• Suitable for:
  • Offshore
  • Marine
  • Chloride environments

EN / DIN Equivalents

For international project compatibility:

ASTM Grade	EN Equivalent	DIN Equivalent
A105	EN 10222-2 P250GH	DIN 1.0460
LF2	EN 10222-4 P215NL	DIN 1.0425
F304	EN 10222-5 X5CrNi18-10	DIN 1.4301
F316	EN 10222-5 X5CrNiMo17-12-2	DIN 1.4401

Standards Mapping to Engineering Selection

Requirement	Standard Reference
Dimensional compliance	ASME B16.47
Pressure-temperature rating	ASME B16.47 + ASME Section II
Material properties	ASTM standards
Inspection & testing	ASME Section V / ASTM
Certification	EN 10204

6. Material & Grade Options

Material selection is driven by:

• Operating pressure
• Temperature range
• Corrosive environment
• Mechanical loading
• Design life requirements

Carbon Steel Flanges

ASTM A105

• Standard forged carbon steel
• Suitable for:
  • Ambient to moderate temperatures
  • Hydrocarbon service
• Limitations:
  • Not suitable for low-temperature brittle conditions

ASTM A350 LF2

• Low-temperature carbon steel
• Improved notch toughness
• Suitable for:
  • Sub-zero applications
  • LNG systems

Stainless Steel Flanges

ASTM A182 F304

• Austenitic stainless steel
• Good corrosion resistance
• Used in:
  • Water systems
  • Mild chemical environments

ASTM A182 F316

• Contains molybdenum
• Enhanced resistance to:
  • Chlorides
  • Chemical corrosion
• Suitable for:
  • Marine environments
  • Chemical processing

Alloy Steel Flanges

ASTM A182 F11

• Chromium-molybdenum alloy
• Used in:
  • Moderate temperature service
  • Power plants

ASTM A182 F22

• Higher Cr-Mo content
• Suitable for:
  • High temperature
  • High pressure
  • Steam systems

Duplex / Super Duplex Stainless Steel

Characteristics:

• Dual-phase microstructure (austenite + ferrite)
• Higher strength than austenitic steels
• Superior resistance to:
  • Stress corrosion cracking
  • Pitting corrosion

Applications:

• Offshore platforms
• Seawater systems
• Aggressive chemical environments

Material Comparison Table

Grade	Yield Strength (MPa)	Tensile Strength (MPa)	Temperature Range	Corrosion Resistance	Typical Applications
A105	~250	485–620	-29°C to 425°C	Low	Oil & gas pipelines
LF2	~250	485–620	-46°C to 345°C	Low	LNG, low-temp service
F304	~205	515–720	-196°C to 870°C	Moderate	Water, chemical
F316	~205	515–720	-196°C to 870°C	High	Marine, chemical
F11	~275	415–585	Up to 540°C	Moderate	Power plants
F22	~415	585–760	Up to 600°C	Moderate	High-temp steam
Duplex	~450	620–880	-50°C to 300°C	Very High	Offshore systems

Engineering Considerations in Material Selection

Temperature Limits

• Carbon steel → limited at low temperature
• Stainless steel → wide temperature range
• Alloy steel → high temperature capability

Corrosion Resistance

• Carbon steel → requires coating
• Stainless steel → inherent corrosion resistance
• Duplex → superior in chloride environments

Pressure Suitability

• High-strength materials allow:
  • Reduced thickness
  • Improved load capacity

7. Heat Treatment

Heat treatment ensures:

• Required mechanical properties
• Controlled microstructure
• Stress relief

Normalizing

Process:

• Heating above critical temperature
• Air cooling

Purpose:

• Grain refinement
• Uniform structure
• Improved toughness

Quenching & Tempering

Process:

• Rapid cooling (quenching)
• Controlled reheating (tempering)

Purpose:

• Increase strength
• Improve hardness
• Maintain ductility

Applicable to:

• Alloy steels (F11, F22)

Solution Annealing (Stainless Steel)

Process:

• Heating to high temperature
• Rapid quenching

Purpose:

• Dissolve carbides
• Restore corrosion resistance

Stress Relieving

Process:

• Heating below transformation temperature

Purpose:

• Reduce residual stresses from:
  • Forging
  • Machining

Hardness Control

Typical ranges:

Material	Hardness (HB)
A105	120–187
LF2	120–200
F11/F22	130–220
Stainless Steel	≤ 200

Impact Testing (Charpy V-Notch)

Required for:

• Low-temperature service (LF2)
• Critical applications

Measures:

• Energy absorption capacity
• Resistance to brittle fracture

Manufacturing Process

ANSI B16.47 Flanges are manufactured through controlled processes ensuring dimensional accuracy and structural integrity.

Step 1: Raw Material Inspection

• Verification of:
  • Chemical composition
  • Mechanical properties
• Traceability through:
  • Heat numbers
  • Mill test certificates

Step 2: Forging / Ring Rolling

Open Die Forging

• Used for large flanges
• Provides:
  • Grain flow alignment
  • Structural strength

Ring Rolling

• Produces:
  • Uniform grain structure
  • Controlled dimensions

Step 3: Heat Treatment

• Applied as per material grade
• Ensures:
  • Mechanical property compliance
  • Stress relief

Step 4: CNC Machining

Includes:

• Outer diameter machining
• Bore machining
• Facing operations

Ensures:

• Dimensional precision
• Surface finish control

Step 5: Facing Machining

• RF serration machining
• RTJ groove cutting

Critical for:

• Gasket sealing performance

Step 6: Bolt Hole Drilling

• CNC drilling for:
  • Positional accuracy
  • Angular precision

Tolerance control:

• Bolt hole alignment
• Pitch circle accuracy

Step 7: Marking & Traceability

Includes:

• Heat number
• Material grade
• Size and pressure class
• Standard reference (ASME B16.47)

Large-Diameter Machining Challenges

• Handling heavy components
• Maintaining flatness across large surfaces
• Controlling distortion during machining
• Ensuring concentricity

Dimensional Control Discipline

Critical checks:

• Bore alignment
• Face flatness
• Bolt hole positioning
• Thickness uniformity

Surface Finish Options

Surface treatment is applied based on:

• Environmental exposure
• Corrosion risk
• Project specifications

Available Surface Finishes

Anti-Rust Oil Coating

• Temporary protection
• Used during storage and transport

Zinc Plating

• Corrosion protection
• Suitable for:
  • Mild environments

Hot-Dip Galvanizing

• Thick zinc coating
• Suitable for:
  • Outdoor and marine environments

PTFE Coating

• Chemical resistance
• Low friction surface

Black Oxide

• Minimal corrosion resistance
• Used for indoor applications

Passivation (Stainless Steel)

• Enhances oxide layer
• Improves corrosion resistance

Surface Roughness (Ra Values)

Facing Type	Surface Roughness (Ra)
Raised Face (RF)	3.2 – 6.3 µm
Smooth Finish	≤ 3.2 µm
RTJ Groove	Precision machined

Serrated Finish Requirements

• Concentric or spiral serrations
• Ensures:
  • Gasket grip
  • Leakage prevention

8. Dimensional Reference Tables (Indicative Engineering Data)

The following tables provide representative dimensional logic for ANSI B16.47 Flanges. Final dimensions shall always be verified against ASME B16.47 tables (Series A / Series B) for project-specific compliance.

A. Dimension Table (Sample — Series A)

NPS (in)	Class	Bolt Size (in)	No. of Bolts	Bolt Circle Dia (mm)	Flange Thickness (mm)
26	150	1-1/2	28	1245	69
30	150	1-1/2	32	1397	73
36	150	1-5/8	36	1651	79
42	150	1-3/4	40	1905	86
48	150	1-3/4	44	2159	92
54	150	2	48	2413	98
60	150	2	52	2667	105

Engineering Observations

• Increase in NPS results in:
  • Higher bolt count
  • Larger bolt diameters
  • Increased flange thickness
• Designed to:
  • Maintain gasket compression
  • Resist bending and rotation

B. Pressure Rating Table (ASME B16.47 Basis)

Pressure ratings depend on:

• Material group
• Temperature
• Pressure class

Example — Carbon Steel (A105)

Class	Pressure at 38°C (bar)	Pressure at 200°C (bar)	Pressure at 400°C (bar)
75	5.2	4.5	2.6
150	19.6	15.6	10.2
300	51.1	40.0	26.6
400	68.1	53.3	35.4
600	102.1	80.0	53.3
900	153.2	120.0	80.0

Temperature Derating

• Allowable pressure reduces with temperature increase
• Governed by:
  • Material allowable stress (ASME Section II)

C. Torque Chart (ASTM A193 B7 Bolting)

Torque values depend on:

• Bolt diameter
• Lubrication condition
• Desired preload

Torque Values (Indicative)

Bolt Size (in)	Torque (Nm) — Lubricated	Torque (Nm) — Dry
1″	900	1200
1-1/4″	1600	2100
1-1/2″	2800	3600
1-3/4″	4500	5800
2″	7000	9000
2-1/2″	12000	15000

Engineering Notes

• Lubrication reduces friction → improves preload accuracy
• Torque values are approximate; actual preload must be verified through:
  • Bolt stress calculation
  • Tensioning methods (hydraulic tensioners for large diameters)

D. Preload Calculation Guide

1. Bolt Stress Formula

Bolt stress is defined as:

   

Where:

• σ = Bolt stress
• F = Axial preload force
• A = Tensile stress area

2. Torque–Preload Relationship

   

Where:

• T = Applied torque
• K = Nut factor (typically 0.15–0.25)
• F = Preload force
• d = Nominal bolt diameter

3. Axial Separation Force

Internal pressure creates a separating force:

   

Where:

• Fp = Pressure-induced force
• P = Internal pressure
• Ag = Effective gasket area

4. Engineering Condition for Leak Prevention

For sealing integrity:

Bolt preload force > Internal separation force

5. Sample Calculation

Given:

• Pressure (P) = 20 MPa
• Gasket area (Ag) = 0.5 m²
• Bolt diameter = 36 mm
• Nut factor (K) = 0.2

Step 1: Separation Force

Fp = 20 × 10⁶ × 0.5 = 10,000,000 N

Step 2: Required Bolt Preload

Assume safety factor = 1.5

Required preload:

F = 1.5 × 10,000,000 = 15,000,000 N

Step 3: Torque Calculation

   

T = 0.2 × 15,000,000 × 0.036

T = 108,000 Nm

Engineering Interpretation

• Large-diameter flanges require:
  • High bolt preload
  • Controlled tightening procedures
• Hydraulic bolt tensioning is preferred over torque for accuracy

E. Mechanical Properties Table

Material	Yield Strength (MPa)	Tensile Strength (MPa)	Elongation (%)	Hardness (HB)	Impact (J)
A105	≥250	485–620	≥22	120–187	—
LF2	≥250	485–620	≥22	120–200	≥27 @ -46°C
F304	≥205	515–720	≥30	≤200	—
F316	≥205	515–720	≥30	≤200	—
F11	≥275	415–585	≥20	130–200	—
F22	≥415	585–760	≥20	140–220	—
Duplex	≥450	620–880	≥25	≤290	—

F. Corrosion Resistance Table

Material	Marine	Acidic	Hydrocarbon	High Humidity
Carbon Steel	Low	Low	Good	Low
SS304	Moderate	Moderate	Good	Good
SS316	High	High	Good	High
Alloy Steel	Moderate	Low	Good	Moderate
Duplex	Very High	High	Excellent	Very High

9. Inspection & Quality Control

Inspection of ANSI B16.47 Flanges is performed to ensure:

• Pressure integrity
• Material compliance
• Dimensional accuracy
• Traceability

Material Verification

PMI (Positive Material Identification)

• Confirms alloy composition
• Ensures correct material grade

Non-Destructive Testing (NDT)

Ultrasonic Testing (UT)

• Detects internal defects
• Ensures forging integrity

Magnetic Particle Inspection (MPI)

• Detects surface and near-surface cracks
• Applicable to ferromagnetic materials

Dye Penetrant Inspection (DPI)

• Detects surface discontinuities
• Used for stainless steel

Dimensional Inspection

Checks include:

• Outer diameter
• Bore diameter
• Bolt circle diameter
• Bolt hole alignment
• Thickness
• Facing geometry

Hardness Testing

• Ensures compliance with:
  • Material specifications
• Prevents:
  • Over-hardening (brittleness)
  • Under-hardening (low strength)

Hydrostatic Testing (If Applicable)

• Verifies pressure containment capability
• Typically applied in assembled systems

Third-Party Inspection (TPI)

Inspection agencies:

• Client-approved inspectors
• Independent verification bodies

Scope:

• Witnessing tests
• Reviewing documentation
• Final inspection release

Certification

EN 10204 3.1

• Manufacturer test certificate
• Confirms:
  • Chemical composition
  • Mechanical properties

EN 10204 3.2

• Third-party validated certificate
• Required for:
  • Critical EPC projects
  • Offshore and high-risk applications

Traceability System

Maintained through:

• Heat number stamping
• Batch tracking
• Material certificates
• Inspection records

Quality Control Objectives

• Eliminate dimensional deviation
• Ensure gasket sealing reliability
• Maintain pressure integrity under operating conditions

10. Industries Served

ANSI B16.47 Flanges are deployed across sectors where large-diameter, pressure-retaining joints are required under controlled engineering conditions.

Oil & Gas Transmission Pipelines

Used in:

• Cross-country crude oil pipelines
• Natural gas transmission systems
• Gathering and distribution networks

Engineering requirements:

• High-pressure integrity
• Resistance to cyclic loading
• Field assembly and maintenance capability

Flanges enable:

• Sectional isolation
• Inline inspection (pigging access points)
• Maintenance without pipeline cutting

Refineries

Installed in:

• Process piping systems
• Crude and vacuum distillation units
• Hydroprocessing and catalytic units

Operational requirements:

• High temperature and pressure resistance
• Chemical compatibility
• Shutdown inspection accessibility

Petrochemical Plants

Applications include:

• Bulk chemical transfer lines
• Polymer and intermediate product pipelines
• Utility systems (steam, cooling water)

Material selection is driven by:

• Corrosion resistance
• Chemical compatibility
• Process temperature

Power Generation

Used in:

• Cooling water systems
• Condenser lines
• Flue gas and exhaust systems

Key considerations:

• Thermal expansion loads
• Large volumetric flow
• Structural support integration

LNG Terminals

Installed in:

• Cryogenic pipelines
• Regasification systems
• Storage tank connections

Requirements:

• Low-temperature toughness
• Leak-tight sealing
• Dimensional stability

Offshore & Marine Systems

Used in:

• Offshore platforms
• Subsea-to-topside connections
• Seawater handling systems

Critical factors:

• Corrosion resistance (chloride exposure)
• Fatigue resistance
• Weight optimization

Water Transmission & Infrastructure

Applications:

• Municipal water supply pipelines
• Desalination plants
• Flood control systems

Design considerations:

• Large-diameter flow efficiency
• Corrosion protection
• Ease of installation and maintenance

11. Export Capability & Global Supply

Super Industries supplies ANSI B16.47 Flanges for international EPC projects, aligned with documentation, logistics, and compliance requirements.

Regions Served

• United States
• European Union
• Middle East (UAE, Saudi Arabia, Qatar, Kuwait)
• Southeast Asia
• Africa (project-based supply)

Packaging for Large-Diameter Flanges

Due to size and weight constraints:

• Wooden crates (ISPM-15 compliant)
• Steel-reinforced palletization
• Individual flange protection:
  • Plastic caps for faces
  • Edge protectors
  • Anti-corrosion wrapping

Export Documentation

Supplied documentation includes:

• Commercial Invoice
• Packing List
• Certificate of Origin
• Mill Test Certificates (EN 10204 3.1 / 3.2)
• Inspection Reports
• Heat Treatment Charts
• NDT Reports

Project Logistics Handling

• Coordination with EPC contractors
• Lot-wise dispatch based on project schedule
• Handling of heavy-lift cargo
• Containerization or break-bulk shipment

Compliance Documentation

Ensures alignment with:

• ASME B16.47
• ASTM material standards
• Project specifications
• Third-party inspection requirements

12. Procurement & Installation Guidelines

This section is structured for EPC contractors, site engineers, and commissioning teams.

A. Pre-Installation Checks

Verify:

• Flange size, class, and rating
• Material grade and certification
• Facing condition (RF / RTJ)
• Bolt and gasket compatibility

Inspection points:

• Surface damage
• Corrosion or contamination
• Dimensional compliance

B. Gasket Installation Practices

• Select gasket as per:
  • Pressure class
  • Temperature
  • Fluid compatibility
• Ensure:
  • Clean seating surfaces
  • Proper alignment
  • No reuse of compressed gaskets

C. Bolt Tightening Sequence

Use cross-tightening (star pattern):

1. Initial snug tightening
2. Intermediate torque (30–50%)
3. Final torque (100%)

Objective:

• Uniform gasket compression
• Prevention of flange rotation

D. Torque Application Stages

Typical tightening sequence:

• Stage 1 → 30% of final torque
• Stage 2 → 60% of final torque
• Stage 3 → 100% torque
• Stage 4 → Final circular pass

E. Lubrication Requirements

Apply lubricant to:

• Bolt threads
• Nut bearing surfaces

Purpose:

• Reduce friction variability
• Improve preload accuracy

F. Re-Torque Requirements

Re-tightening may be required:

• After initial pressurization
• After thermal cycling

Conditions:

• Only when system is depressurized
• Follow project procedures

G. Field Inspection Checkpoints

Verify:

• Bolt tension consistency
• Gasket seating condition
• Alignment of flanges
• Absence of leakage during hydrotest

H. Storage & Handling

Storage

• Keep in dry, covered area
• Avoid direct ground contact
• Maintain protective coatings

Handling

• Use lifting equipment for large diameters
• Avoid:
  • Dropping
  • Edge damage
  • Face scratching

13. Custom Engineering Capabilities

Super Industries manufactures ANSI B16.47 Flanges with project-specific customization, aligned with EPC requirements.

Non-Standard Diameters

• Custom sizes beyond standard NPS range
• Designed as per client drawings

Custom Drilling Patterns

• Non-standard bolt hole configurations
• Matching legacy or retrofit systems

Special Thickness Flanges

• Increased thickness for:
  • High external loads
  • Structural reinforcement

RTJ Groove Customization

• Machining as per:
  • API ring numbers
  • Project-specific tolerances

Project-Specific Marking

Includes:

• Heat number
• Purchase order reference
• Tag numbers
• Client-specific identification

Engineering Summary

ANSI B16.47 Flanges are critical components in large-diameter piping systems, designed to:

• Maintain pressure integrity
• Enable controlled assembly and disassembly
• Support mechanical and thermal loads
• Ensure leak-tight performance

Engineering performance depends on:

• Correct selection (Series A / Series B)
• Material suitability
• Controlled manufacturing
• Accurate bolt preload
• Proper installation practices

Final Technical Positioning

This document establishes ANSI B16.47 Flanges as:

• ASME-compliant pressure-retaining components
• Suitable for large-diameter, high-load applications
• Compatible with EPC procurement and inspection protocols

Super Industries manufactures these flanges with:

• Controlled dimensional tolerances
• Traceable material systems
• Documented inspection procedures
• Compliance with global project requirements