1. Governing Standards & Classification Compliance

• Design & Dimensions: ASME B16.34 (Valves – Flanged, Threaded and Welding End), flange ends per ASME B16.5 (steel) or ASME B16.1 (cast iron), threaded ends per ASME B1.20.1 (NPT). Face-to-face dimensions follow marine practice or MSS SP-72 where applicable.

• Class Society Approvals: Available with type approval certificates from ABS, Bureau Veritas (BV), DNV, Lloyd’s Register (LR), RINA, CCS, and others upon request.

• Marking: Full traceable marking in accordance with MSS SP-25, including material grade, heat number, pressure class, and manufacturer identification.

2. Design Features

• Angle Body Configuration: Single-piece 90° body eliminates one piping elbow, minimizing flow resistance and installation footprint.

• Bonnet Type: Bolted bonnet for sizes 2″ and above (enables easy in-line maintenance); screwed bonnet for smaller sizes; both designs allow access to internal trim.

• Renewable Seat & Disc: Hard-face or corrosion-resistant seating surfaces can be re-lapped or replaced without removing the valve body from the line.

• Rising Stem with Acme Thread: Gives clear visual open/close indication; Acme thread form handles high operating thrust smoothly.

• Backseat Arrangement: When fully open, the stem seals against a backseat bushing, preventing leakage at the stuffing box and permitting repacking under pressure.

• Deep Stuffing Box: Multiple rings of PTFE or graphite packing, compressed by a gland flange, maintain a reliable stem seal during thermal cycling.

3. Materials of Construction
Materials are selected per ASTM specifications to suit the service medium:

• Body & Bonnet: ASTM A216 WCB (carbon steel), ASTM A351 CF8/CF8M (stainless steel), ASTM B62/B584 C83600 (bronze), ASTM A536 (ductile iron), or ASTM B148 C95800 (nickel-aluminum bronze for seawater).

• Trim (Seat/Disc): Bronze, 316 stainless steel, Monel, or resilient insert (Neoprene/PTFE for bubble-tight shut-off in water).

• Stem: ASTM A276 Type 410 or 316 stainless steel, Monel for enhanced corrosion protection.

• Gaskets & Packing: Graphite/PTFE suitable for high-temperature and fire-safe applications.

4. Pressure-Temperature Ratings

• Rating Basis: ASME B16.34 Class, typically Class 150 or Class 300. (e.g., Class 150 WCB valve: MAWP 285 psi at 100°F, derating with temperature increase.)

• Test Pressure: Shell test at 1.5× rated working pressure; seat closure test at 1.1× rated pressure, conducted per API 598 (or MSS SP-61). Optional low-pressure air seat tests available.

5. Quality Assurance & Certification

• 100% hydrostatic shell and seat testing on every valve.

• EN 10204 Type 3.1 material certificates provided as standard; Type 3.2 available upon request with class society surveyor witness.

• Positive Material Identification (PMI) and NDE (ultrasonic, dye penetrant) reports offered as optional documentation.

6. Typical Marine Applications

• Seawater cooling, ballast, bilge, and fire-fighting mains.

• Fuel oil transfer, lubricating oil, and thermal oil circuits.

• Steam, condensate, and auxiliary boiler feedwater.

• Compressed air, inert gas, and cargo system auxiliary lines.

• Any location where space constraints demand a compact, elbow-free valve arrangement.

7. Key Advantages

• Space-Efficient: Eliminates a separate elbow, reducing envelope dimensions in crowded engine rooms.

• Robust for Sea Conditions: Proven resistance to ship vibration, dynamic loads, and corrosive salt-laden atmospheres.

• Certification Ready: Full documentation package supports flag-state and classification society surveys, simplifying vessel commissioning.

• Low Life-Cycle Cost: Renewable seats and backseat repacking capability minimize downtime and spare parts expense.