Resilient Seat Double Three Eccentric Flanged Butterfly Valve D342X D343X

Resilient Seat Double Three Eccentric Flanged Butterfly Valve Purpose

The butterfly valve is suitable for use in metallurgy, chemical power, municipal engineering and medium such as water, oi land air pipeline, as cutting fluid and adjust medium flow rate, etc.

Resilient Seat Double Three Eccentric Flanged Butterfly Valve Definition and Components

1.1 Product Definition

D342X/D343X are resilient seat double/triple eccentric flanged butterfly valves, representing advanced technical upgrades over standard concentric butterfly valves (D341X) for demanding applications.

D342X - Double Eccentric Butterfly Valve:

• First Offset: Stem axis offset from disc centerline
• Second Offset: Stem axis offset from valve/pipe centerline
• Result: Disc lifts away from seat during initial opening, minimizing friction and wear

D343X - Triple Eccentric Butterfly Valve:

• Third Offset: Seat cone angle offset (conical seat design)
• Revolutionary Advantage: Zero contact between disc and seat throughout entire operation until final closure
• Sealing Principle: "The tighter it closes, the better it seals" through wedge action

Resilient Seat: Typically refers to composite structures where a metallic seat body incorporates elastic sealing elements (PTFE, reinforced graphite, special alloys) or features laminated metal/graphite designs. This provides superior temperature/pressure resistance compared to rubber seats and often includes fire-safe functionality.

1.2 Main Components

 Role, Characteristics, and Application Scenarios of Resilient Seat Double Three Eccentric Flanged Butterfly Valve in Pipelines

2.1 Pipeline Functions

Bidirectional Isolation: Near-zero leakage shutoff in both flow directions

Flow Regulation: Improved flow characteristics for throttling applications

Safety Shutdown: Critical isolation point for Emergency Shutdown (ESD) systems

Severe Service Handling: Suitable for abrasive, high-temperature, high-pressure, or corrosive media

2.2 Operational Features Comparison

2.3 Application Scenario Diagram

Fire protection water supply Typical Industries & Services:

• Oil & Gas: Pipeline transmission, refinery process lines, offshore platforms
• Power Generation: Main steam, feedwater, cooling water systems
• Petrochemical: Catalytic cracking units, ethylene plants, high-pressure reactors
• Marine: Shipboard systems, ballast, fuel lines
• LNG: Cryogenic applications (special designs required)
• Water Treatment: High-pressure pump discharge, backwash systems

Resilient Seat Double Three Eccentric Flanged Butterfly Valve Standards: Materials, Design, and Connections

3.1 Material Standards

3.2 Design & Performance Standards

3.3 Connection Standards

Face-to-Face Dimensions: ISO 5752 Series 20 (aligned with API 609)

How to Select Resilient Seat Double Three Eccentric Flanged Butterfly Valve

4.1 Technical Specification Development

Develop a comprehensive Valve Data Sheet including:

Butterfly Valve for Water Service Conditions:

• Fluid composition (including abrasives/corrosives)
• Operating pressure/temperature (min/max/design)
• Cycle frequency (continuous/intermittent)
• Ambient conditions (offshore, cryogenic, etc.)

Design Requirements:

• Pressure class (ANSI/PN) and design code
• Temperature rating
• Leakage class (ANSI/FCI 70-2 Class VI, zero leakage)
• Fire-safe requirements (API 607/6FA)
• Fugitive emission compliance (ISO 15848, TA-Luft)
• NACE MR0175 for sour service
• Special requirements: X-ray, PMI, NDE

Material Selection Matrix:

4.2 Supplier Qualification Process

Key Fire Protection System Supplier Certifications to Verify:

✅ API 609 Monogram License

✅ API 607/6FA Fire Test Certificates (for specific models)

✅ ISO 9001:2015 Quality Management

✅ CE/PED for European market

✅ NACE MR0175/ISO 15156 compliance

✅ Environmental certifications (ISO 14001)

4.3 Ordering Documentation

Ensure purchase orders include:

• Detailed technical specifications
• Reference to all applicable standards
• Inspection and test requirements (ITP)
• Witness/hold points for critical inspections
• Packaging and marking requirements
• Documentation deliverables list

Pre-Shipment Inspection for Export Resilient Seat Double Three Eccentric Flanged Butterfly Valve and Key Considerations

5.1 Comprehensive Inspection Protocol

Stage 1: Documentation Review

• Material Test Certificates (EN 10204 3.1/3.2)
• Original API/ISO certificates
• Non-Destructive Examination reports
• Heat treatment charts
• Final assembly and test reports
• Paint/coating certificates

Stage 2: Visual & Dimensional Inspection

Stage 3: Pressure Testing (Per API 598)

Test Sequence:

1. Shell Test: 1.5 × PN rating, water, ≥15 min duration
2. Seat Test (Low Pressure): Air/N2 at 0.6 MPa, soap solution detection
3. Seat Test (High Pressure): 1.1 × PN rating, water, ≥15 min duration
4. Special Tests (if specified):

• Fire-safe simulation
• Cryogenic testing
• Fugitive emission testing

Stage 4: Functional Testing

• Full 90° operation verification
• Torque measurement at opening/closing
• Position indicator accuracy check
• Limit switch function (if automated)

5.2 Critical Inspection Focus for Eccentric Valves

• Offset Dimension Verification: Use precision instruments to confirm first, second, and (for D343X) third offset values
• Seat Installation Quality: Ensure proper compression, no gaps in laminated structures
• Bearing Clearance Check: Verify radial/axial play within specifications
• Fire-Safe Features: Confirm secondary metal seat contact surfaces

5.3 Export Preparation Checklist

Cleaning & Preservation:

• Complete internal drying after hydrotest
• Application of VCI (Vapor Corrosion Inhibitor) coatings
• Desiccant placement (calculate based on volume)
• Rust preventive on machined surfaces

Protective Packaging:

• Flange Protection: Minimum 3mm thick plastic/metal covers bolted (not taped) in place
• Stem/Gear Protection: Shrink wrapping with silica gel packets
• Internal Blocking: Wooden blocks to prevent movement during transit
• External Crating: ISPM-15 compliant wooden crates with proper reinforcement

Marking & Identification:

CRATE MARKING REQUIREMENTS:

• Consignee/Consignor information
• Package number and gross/net weight
• Handling symbols (fragile, this side up, keep dry)
• Center of gravity indication for heavy items

VALVE BODY MARKING (per MSS SP-25):

• Manufacturer's name/trademark
• Pressure class designation
• Material designation
• Directional flow arrow (if applicable)
• Heat number for pressure parts
• Fire-safe designation (if applicable)

Documentation Package:

• Commercial invoice (3 copies)
• Packing list (detailed, per crate)
• Certificate of origin
• Bill of lading/air waybill
• Insurance certificate
• Technical documentation in waterproof pouch:
• Data book with all test records
• Material certificates
• Installation, operation, maintenance manual
• Certificates of conformity

Special Precautions:

• Valve Position: Secure disc in slightly open position (5-10°) to prevent seat compression during transport
• Environmental Compliance: Verify adherence to RoHS, REACH, TSCA as per destination country

Third-Party Inspection: For critical applications, engage independent inspectors (DNV, BV, SGS) for:

• Witness of final testing
• Review of documentation
• Release certification

Common Export Defects to Avoid:

• Inadequate preservation leading to corrosion
• Improper blocking causing internal damage
• Missing or incorrect documentation
• Non-compliant wood packaging (lack of ISPM-15 marking)
• Insufficient protection of machined surfaces

5.4 Final Release Criteria

Before shipment authorization, verify:

All inspection/test reports are complete and signed

Non-conformities have been properly addressed and closed

Packaging meets all contractual and international shipping requirements

Documentation package is complete and accurate

Special customer requirements have been fulfilled

Shipping marks are clearly visible on all sides of crates

Resilient Seat Double Three Eccentric Flanged Butterfly Valve Main dimensions(mm)

Note:1. Other specifications and flange standards are available upon request.

2. Design and specifications are subject to change without prior notice.