Hard Seated Nickel Alloy Casted Top Entry ball valve

Hard Seated Nickel Alloy Cast Top-Entry Ball Valve is a specialty control valve that integrates a hard-seated sealing structure, nickel alloy corrosion resistance, cast manufacturing adaptability, and top-entry maintenance advantages. It is specifically designed for severe operating conditions involving strong corrosion, high temperature, high pressure, and frequent operation. It is suitable for chemical, petrochemical, and metallurgical industries, providing reliable flow control and system isolation for corrosive media. Its core advantages include corrosion and wear resistance, stable sealing, and efficient maintenance, effectively addressing common issues such as seal failure, corrosion damage, and difficult servicing under harsh conditions.

Structural design focuses on hard-seal, corrosion resistance, and top-entry maintenance:

• The valve body is made from high-quality corrosion-resistant nickel alloys such as Monel (Monel 400/K-500), Hastelloy (C-276/C-22), or Inconel (625/825) and formed by precision casting. The dense casting structure and high dimensional accuracy ensure long-term resistance to corrosive media and pressure impact.

• The hard-seated design uses nickel alloy for both ball and seats. Sealing surfaces are overlaid with Stellite 6/21 or cobalt-based hard alloy (hardness ≥ HRC60), forming a “nickel alloy + hard seal” composite structure with enhanced wear resistance, high-temperature oxidation, and corrosion protection. The sealing surfaces are precision-ground to ensure tight contact, achieving leakage rates of ANSI B16.104 Class V.

• The top-entry design allows complete removal of core components (ball, seats, stem) from the top without removing the valve body or pipeline, significantly reducing maintenance time.

• The stem is integrally cast from nickel alloy, nitrided, and uses dual packing of flexible graphite and metal braid to prevent stem leakage. Actuation options include manual, electric (smart control), and pneumatic (explosion-proof), accommodating various control requirements.

Key technical parameters:

• Nominal sizes: DN15–DN400 (1/2"–16")

• Pressure ratings: PN10–PN420 (Class 150–2500 LB)

• Operating temperature: –196 °C to 600 °C (suitable for cryogenic corrosive media at low temperatures, and high-temperature chemical/metallurgical processes)

• Corrosion resistance: NACE MR0175/MR0103, suitable for strong acids and bases (pH 0–14), Cl⁻/H₂S/CO₂-containing media

• Hard-seated design suitable for frequent operation, with service life exceeding 100,000 cycles

• Connections: Flanged (ASME B16.5, GB/T 9113), butt-welded; sealing surfaces support RF and RTJ types

Manufacturing and testing strictly follow API 6D, ASME B16.34, and API 598 standards. Each valve undergoes corrosion immersion testing, hard-seal performance testing, hydrostatic strength testing, and non-destructive inspection (UT/RT/MT) to ensure suitability for severe service conditions.

Performance advantages:

1. Dual hard-seal and corrosion resistance – nickel alloy resists multiple corrosive media, hard-seated structure withstands wear and high temperature, with service life 3–5 times longer than soft-seated valves.

2. Efficient maintenance – top-entry design allows core component servicing without removing the pipeline, minimizing downtime.

3. Stable and reliable operation – tight hard-seal fit ensures zero seal failure, even under high-pressure, high-temperature, and frequent operation conditions.

Applications: Suitable for chemical acid/base solutions, sulfur-containing petrochemical media, high-temperature metallurgical flue gas, offshore seawater treatment, etc. Typical installations include chemical reactor inlets/outlets, petrochemical hydroprocessing units, high-temperature metallurgical pipelines, and acid/base storage tank outlets under highly corrosive and severe conditions. It is a critical control device for ensuring stable system operation.