800LB Mod-forged Steel Globe Valve

Description

TECHNICAL DATA SHEET: 800LB MOD-FORGED STEEL GLOBE VALVE

1. GENERAL SPECIFICATION

Valve Type: Bolted Bonnet Globe Valve, Outside Screw & Yoke (OS&Y), Rising Stem
Operation: Handwheel (Standard), Gear Operator (Optional), Electric/Pneumatic Actuator (Optional)
Flow Direction: Flow Under Plug (Standard, as per API 602/ASME B16.34)
Design Code: API 602 / ASME B16.34
Face-to-Face: ASME B16.10
Inspection & Testing: API 598 / Shell MESC SPE 77/300

2. PRESSURE & TEMPERATURE RATINGS

Pressure Class: ASME 800 LB (PN 100 Equivalent)
Max. Working Pressure (MWP): Per ASME B16.34 for Group 1.1 Materials
Temperature Range:
- Min. Temp: -29°C (-20°F) (Standard)
- Max. Temp: +425°C (+800°F) (For A105, limited by seat material)
Pressure-Temperature Ratings: As per ASME B16.34 Tables for A105 Material.

3. MATERIAL SPECIFICATION (PER ASTM STANDARDS)

Body & Bonnet: Carbon Steel, ASTM A105 (Forged)
Stem: Stainless Steel, ASTM A182 F6a (13Cr) or F316, with Hardened Surface
Disc (Plug): ASTM A105 + Hardfaced Sealing Surface: Stellite 6 (AWS ERCoCr-A) applied by overlay welding. (Minimum 1.5mm thickness after machining).
Seat Ring: ASTM A105 + Hardfaced Sealing Surface: Stellite 6 (AWS ERCoCr-A) applied by overlay welding. (Integral or welded-in).
Gasket: Spiral Wound Gasket, Stainless Steel (SS316) Filler + Flexible Graphite Filler, SS316 Inner/Outer Ring. (Alternative: Ring Type Joint (RTJ) per ASME B16.20).
Bolting: ASTM A193 B7 Studs / ASTM A194 2H Nuts
Packing: Flexible Graphite (Standard), PTFE or Graphite/PTFE Composite (Optional for lower temps)
Packing Box: Live-loaded packing gland (Standard) for reliable sealing.
Yoke: ASTM A216 WCB (Cast) or A105 (Forged)
Handwheel: Ductile Iron (ASTM A536) or Carbon Steel (AISI 1018)

4. CONNECTIONS & SEALING

End Connections:
- Standard: Raised Face (RF) Flange per ASME B16.5 Class 800.
- Alternative: Ring Type Joint (RTJ) Flange per ASME B16.5 Class 800.
Face Finish: ASME B16.5 RF Finish (125-250 µin Ra)
Body-Bonnet Sealing: Spiral Wound Gasket (as above) or RTJ (if specified).

5. STELLITE SEALING (CRITICAL FEATURE)

Sealing Surfaces: Both Disc (Plug) and Seat Ring mating surfaces.
Material: Stellite 6 (Cobalt-Chromium-Tungsten-Carbon Alloy, ASTM F75 equivalent).
Application Method: Plasma Transferred Arc (PTA) or TIG Overlay Welding.
Thickness: Minimum 1.5mm (0.060″) after final machining.
Hardness: Approx. 40-45 HRC.
Benefits: Excellent galling resistance, high erosion resistance, good high-temperature strength, superior corrosion resistance compared to base A105.

6. DESIGN FEATURES

Bonnet Joint: Bolted Bonnet (Standard). Welded Bonnet (Optional for severe service).
Stem Design: Rising Stem, Non-Rotating. Backseat Feature (API 602 Requirement).
Stem Sealing: Multiple rings of flexible graphite packing, gland follower, live-loading springs.
Stem Nut: Bronze or CuNi alloy (self-lubricating).
Leakage Class: Class IV (Metal Seat) per API 598 (Standard). Class V or VI achievable with lapping (Consult Factory).
Fire Safe Design: API 607 / API 6FA compliant packing & secondary metal seals (Optional).

7. TESTING (PER API 598)

Shell Test: 1.5 x Class Rating Pressure (1200 PSI) with water.
Seat Test: 1.1 x Class Rating Pressure (880 PSI) with air or water (both directions for globe valve).
Backseat Test: 1.1 x Class Rating Pressure (880 PSI) with air or water.
High Pressure Gas Test (Optional): Per customer specification.
Documentation: Certified Test Reports (CTRs) available.

8. MARKING & IDENTIFICATION

9. PAINTING & PACKING

External Surface Preparation: Blast cleaned to Sa 2½ (ISO 8501-1).
Primer: High-quality epoxy primer.
Finish Coat: Epoxy paint, RAL 7012 (Standard Grey) or customer-specified color.
End Protection: Plastic or Metal Caps/Blinds suitable for Class 800 pressure.
Packing: Wooden crate or export-quality plywood case suitable for marine transport.