Leak-Proof FC Valve Seat for Petroleum - Thermal Spray Coated by China Suppliers and Factory for Oilfield Applications
Product Description
The FC (Failed Close) automatic shut-off valve seat is a core sealing and vulnerable component of gate valves used in oil drilling, production, oil and gas gathering and transportation, downhole operations, and wellhead systems.
The product employs a professional fail-safe shut-off (FC) design. When sudden conditions occur in oilfield equipment, such as power outages, abnormal system pressure, or actuator malfunctions, the valve seat, in conjunction with the valve structure, automatically and quickly closes, locking the oil and gas medium passage. This fundamentally prevents safety accidents such as blowouts, medium leaks, and equipment malfunctions, strictly adhering to the safety standards for high-risk oilfield operations.
The valve seat uses high-strength alloy structural steel as its base material, precision-machined using CNC lathes and grinders to ensure assembly accuracy. The sealing surface undergoes a high-velocity oxygen fuel spraying (HVOF) tungsten carbide (WC) strengthening process, resulting in a coating with strong adhesion, high hardness, erosion resistance, and corrosion resistance. It can withstand harsh operating conditions such as sandy mud, high-pressure oil and gas, and corrosive media in oilfields for extended periods, significantly improving the sealing stability and service life of the gate valve. It is a core component of valve systems in onshore oilfields and offshore drilling platforms.
Product Specifications
| Type | FC Valve Seat |
| Nominal Diameter | 1-13/16"/ 2-1/16"/ 2-9/16"/ 3-1/16"/ 3-1/8"/ 4-1/16"/ 5-1/8"/ 6-5/8"/ 7-1/16"/ 9"/ 11"/ 13-5/8" (custom sizes available upon request) |
| Working Pressure | 2000psi(2K)/ 3000psi(3K)/ 5000psi(5K)/ 10000psi(10K)/ 15000psi(15K)/ 20000psi(20K) (Customized solutions are available for high-temperature working conditions.) |
| Media | Crude oil, natural gas, drilling mud, sand-containing oil and gas, corrosive oil and gas media |
| Material | High-strength alloy structural steel (42CrMo/40CrNiMo premium grade) |
| Working Temperature | -46℃ - +121℃ |
| Hardness | HRC75 |
| Bonding Strength | ≥70MPa |
| Porosity | <1% |
| Surface Treatment | Supersonic spraying of cobalt-bonded tungsten carbide (WC/Co) / cobalt-chromium-bonded tungsten carbide (WC/CoCr) / cobalt-chromium tungsten alloy (Stellite 20#/NiCr) / nickel-chromium-bonded chromium carbide (Cr₃C₂/NiCr) / nickel-based alloy (Ni60/Ni55) / nickel-based tungsten carbide (WC/Ni) |
| Coating Thickness | 0.03–0.5mm (Customizable) |
| Compatible Equipment | Oilfield gate valves, Christmas tree gate valves, drilling high-pressure valves |
| Pressure Rating | Suitable for high-pressure oilfield conditions (custom pressure ratings available) |
| Sealing Performance | Zero leakage under high pressure, suitable for stringent sealing requirements in oilfields |
| Application Areas | Onshore oilfields, offshore drilling platforms, oil and gas gathering and transmission pipelines, downhole equipment |
Product Features
🔒 1. Fail-Safety Assurance
Employs FC (Failed Close) automatic shut-off design, quickly closing and locking in case of power failure or equipment malfunction to prevent oil and gas leaks, complying with oilfield safety operation regulations.
🛡️ 2. Ultra-Wear-Resistant and Erosion-Resistant
The sealing surface features a tungsten carbide thermal spray coating with a hardness ≥ HRC75, strongly resisting high-speed erosion from sand-containing media, resulting in a service life far exceeding that of ordinary valve seats.
⚙️ 3. High-Pressure Sealing Stability
Precision-machined sealing surfaces achieve high precision in smoothness and flatness, ensuring zero leakage and no pressure relief under high-pressure conditions, providing long-lasting and reliable sealing performance.
💪 4. Strong Corrosion and Impact Resistance
Double corrosion resistance of the substrate and coating, suitable for harsh conditions such as salt spray, acidic oil and gas, and mud; the high-strength substrate is impact-resistant, non-deformable, and crack-free.
🔧 5. Precise and Universal Assembly
Standard structural dimensions perfectly match various oil gate valves, facilitating easy installation, smooth opening and closing without jamming, and requiring no equipment modification.
🎯 6. Strong Customization and Adaptability
Supports customization of size, material, coating, and pressure rating to meet the specific needs of different oilfield equipment and operating conditions.
💰 7. Significant Cost Reduction and Efficiency Improvement
Ultra-long service life reduces replacement frequency, lowers equipment downtime and maintenance costs, and improves oilfield operation efficiency.
Product Packaging
📦 Standard Export Packaging Specification
Outer Layer: Fumigation-free plywood box or heavy-duty carton.
Protection: The packaging system is designed to be impact-resistant, moisture barrier, and anti-corrosive, guaranteeing the integrity of the goods during maritime transit.
Product Transportation
Logistics & Delivery
- 🚢 Maritime Transport
- 🚛 Land & Rail (Surface Transport)
Frequently Asked Questions (FAQ)
Q What does FC (Failed Close) mean in an FC valve seat?
FC stands for "Failed Close," which means the valve seat is designed with a fail-safe mechanism. In the event of a power outage, abnormal system pressure, or actuator malfunction, the valve automatically and quickly closes to lock the oil and gas medium passage, preventing blowouts or leaks and ensuring oilfield safety.
Q What surface treatment is applied to the FC valve seat sealing surface?
The sealing surface is treated using High-Velocity Oxygen Fuel (HVOF) thermal spray technology with tungsten carbide (WC)-based coatings, including WC/Co, WC/CoCr, Stellite alloys, Cr₃C₂/NiCr, Ni60/Ni55, and WC/Ni. This results in a coating with hardness ≥ HRC75, porosity <1%, and bonding strength ≥70MPa, offering exceptional wear, erosion, and corrosion resistance.
Q What pressure ratings are available for the FC valve seat?
The FC valve seat is available in working pressures of 2000psi (2K), 3000psi (3K), 5000psi (5K), 10000psi (10K), 15000psi (15K), and 20000psi (20K). Customized solutions for special high-temperature or ultra-high-pressure working conditions are also available upon request.
Q Which gate valve models and equipment are compatible with this valve seat?
The FC valve seat is compatible with oilfield gate valves, Christmas tree gate valves, and drilling high-pressure valves. Its standard structural dimensions are designed to match various oil gate valves used in onshore oilfields, offshore drilling platforms, and oil and gas gathering and transmission pipelines without requiring equipment modification.
Q Can the FC valve seat be customized for special operating conditions?
Yes. The FC valve seat supports full customization including nominal diameter (from 1-13/16" up to 13-5/8" and beyond), coating material type, coating thickness (0.03–0.5mm), pressure rating, and base material grade to meet the specific requirements of different oilfield equipment and extreme operating environments.
Q What packaging and shipping methods are used for export orders?
Products are packed in fumigation-free plywood boxes or heavy-duty cartons with impact-resistant, moisture-barrier, and anti-corrosive protection to ensure product integrity during transit. Shipping is available via maritime transport and land & rail (surface transport) to destinations worldwide.















