Resilient Seat Flanged Butterfly Valve

Resilient Seat Flanged Butterfly Valve Purpose

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

Resilient Seat Flanged Butterfly Valve Definition and Components

D342X: Double/Triple Eccentric Flanged Butterfly Valve

• D: Butterfly Valve
• 3: Driving mode - Manual (Gear operated)
• 4: Connection type - Flanged
• 2: Double offset (First two eccentricities)
• X: Resilient Seat (Rubber or polymer sealing)

D343X: Triple Eccentric Flanged Butterfly Valve

• 3: Triple offset (All three eccentricities)
• X: Resilient Seat (Often with fire-safe capability)

Eccentricity Explained:

Standard (D341X):    0° Offset - Disc rotates around center

Double Eccentric (D342X):

1.Stem offset from centerline (First offset)

2.Stem offset from seat centerline (Second offset)

→ Reduces seat wear, easier operation

Triple Eccentric (D343X):

1.Stem offset from centerline

2.Stem offset from seat centerline

3.Seat cone angle offset (Third offset - conical seat)

→ Zero friction, bubble-tight, bidirectional sealing

Main Components:

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

Fire protection water supply Pipeline Functions:

Primary Roles:

1.Bidirectional Isolation- Zero leakage shut-off in both directions

2.High-Pressure/Temp Regulation- Throttling in severe service

3.Fire-Safe Protection- Secondary metal-to-metal sealing during fire

4.Cavitation/Noise Reduction- Offset design minimizes turbulence

5.Long-term Reliability- Minimal wear due to no-rubbing design

Butterfly Valve for Water Operational Features Comparison:

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

Material Standards:

Design Standards:

Connection Standards:

Face-to-Face Dimensions: ISO 5752 Series 20 (API 609 Table 2)

How to Select Resilient Seat Flanged Butterfly Valve

Technical Specification Checklist:

Critical Specifications to Define:

Service Conditions:

• Fluid type (corrosive, abrasive, sanitary)
• Pressure/Temperature profile (min/max/operating)
• Cycle frequency (occasional/continuous)

Design Requirements:

• Pressure class (ANSI/PN)
• Temperature rating (include thermal shocks)
• Fire-safe requirements (API 607/6FA)
• Fugitive emissions (ISO 15848-1/TA-Luft)
• NACE compliance for sour servic

Material Selection Matrix:

• NACE compliance for sour service

Material Selection Matrix:

Testing & Certification:

Standard: API 598/ISO 5208

Extended: Shell SPE 77/300 or TOTAL GS EP PVV 142

Third-party inspection required (DNV/BV/SGS)

Fire Protection System Supplier Evaluation Criteria:

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

Enhanced Inspection Checklist:

 Specialized Testing for Eccentric Valves:

Seat Tightness Test (Enhanced):

Test Sequence:

• Low-pressure air test: 0.6 MPa for 1 minute (bubble detection)
• Hydrostatic test: 1.1×PN for 15 minutes
• **High-pressure gas test**: Nitrogen at 80% of yield strength
• **Fire-safe test simulation**: Check secondary metal seat contact
• B. Fire Test Verification (API 607/API 6FA):

Review original fire test certificate (not just compliance)

Verify test was on identical design/size/material

Check test duration and leakage rates:

During fire: ≤ 40 ml/min per inch of seat diameter

After fire: Bubble-tight per API 598

Export Preparation Protocol:

Special Packaging Requirements:

• For D343X valves: VCI (Vapor Corrosion Inhibitor) packaging mandatory
• Desiccant calculation: 50g per m³ of crate volume
• Flange protection: 3mm thick plastic covers bolted (not taped)
• Stem/gear protection: Shrink-wrap with silica gel

Documentation Package:

REQUIRED DOCUMENTS:

├── Commercial Documents

│   ├── Commercial Invoice (3 copies)

│   ├── Packing List (detailed by crate)

│   └── Certificate of Origin

├── Technical Documents

│   ├── Data Book (complete valve record)

│   ├── Material Certificates (EN 10204 3.1/3.2)

│   ├── Test Reports (signed by QC manager)

│   └── Calculation Reports (if applicable)

└── Certification

    ├── Fire Test Certificates (API 607/6FA)

├── NACE Compliance Certificate

├── CE Declaration of Conformity

└── Third-party Inspection Release Note

Marking & Identification:

• Body marking per MSS SP-25 (minimum requirements)
• Additional markings for eccentric valves:
• Offset direction indicator
• Fire-safe identification (FS logo)
• Torque direction arrows

Color coding: Standard per customer specs or ISO 14726

Critical Inspection Points for Eccentric Design:

Offset Verification:

Measurement Procedure:

• Measure stem center to disc center (First offset)
• Measure stem center to seat center (Second offset)
• For D343X: Verify conical angle (Third offset)
• Tolerance: ±0.1mm for offsets ≤ 50mm

±0.2mm for offsets > 50mm

Seat Installation Check:

• Resilient seat must be uniformly compressed
• No visible gaps between laminations
• Fire-safe graphite rings properly positioned
• Secondary metal seat concentricity within 0.05mm

Bearing Clearance Check:

• Radial clearance: 0.1-0.3mm (depending on size)
• Axial play: ≤ 0.5mm
• Smooth rotation with no binding through 90° travel

Common Rejection Points:

Pre-Shipment Audit Trail:

INSPECTION RECORD MUST INCLUDE:

1. Photographs (time-stamped):

- General view with serial number

- Offsets measurement

- Seat installation

- Testing setup

Test Data Logs:

- Pressure vs. time graphs

- Torque vs. angle graphs

- Leakage measurement records

Inspector Verification:

- Name/signature/date

- Instrument calibration dates

- Acceptance/rejection with

Final Release Criteria:

• All dimensional checks within tolerance
• All pressure tests passed with signed reports
• Functional tests show smooth operation
• Documentation complete and accurate
• Packaging meets export requirements
• No outstanding non-conformities

Resilient Seat 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.