China Suppliers: Thermal Spray Coated Leak-Proof FC Valve Seat for Petroleum - Durable and Reliable from Factory
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.
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
Q1 What does "FC" mean in FC Valve Seat, and how does the fail-safe mechanism work?
"FC" stands for "Failed Close." This design ensures that when unexpected conditions occur — such as power outages, hydraulic pressure loss, or actuator failures — the valve seat automatically and rapidly closes in conjunction with the gate valve structure. This locks the oil and gas passage without any manual intervention, preventing blowouts, leaks, and other safety hazards common in high-risk oilfield environments.
Q2 What surface treatment process is used on the FC Valve Seat sealing surface?
The sealing surface is treated using High-Velocity Oxygen Fuel (HVOF) thermal spraying technology, applying coatings such as tungsten carbide (WC/Co, WC/CoCr, WC/Ni), chromium carbide (Cr₃C₂/NiCr), nickel-based alloys (Ni60/Ni55), or Stellite alloys. This results in a coating with hardness ≥ HRC75, porosity <1%, and bonding strength ≥70MPa — far exceeding conventional surface treatment methods.
Q3 What pressure ratings and nominal sizes are available for the FC Valve Seat?
The FC Valve Seat is available in working pressures ranging from 2,000 psi (2K) to 20,000 psi (20K). Standard nominal diameters include 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", and 13-5/8". Custom sizes and pressure ratings are available upon request to accommodate specific oilfield equipment requirements.
Q4 Is the FC Valve Seat compatible with existing gate valve equipment without modification?
Yes. The FC Valve Seat is manufactured to standard structural dimensions that are compatible with a wide range of oilfield gate valves, Christmas tree gate valves, and high-pressure drilling valves. It is designed for direct drop-in replacement, enabling smooth installation without any modification to existing valve bodies or actuator systems.
Q5 What are the typical application environments for this valve seat?
The FC Valve Seat is engineered for demanding oilfield environments including onshore oil and gas fields, offshore drilling platforms, oil and gas gathering and transmission pipelines, and downhole equipment. It performs reliably in media such as crude oil, natural gas, drilling mud, sand-laden fluids, and corrosive gases across a temperature range of -46°C to +121°C.
Q6 Can the FC Valve Seat be customized for specific oilfield project requirements?
Absolutely. Full customization is supported, including adjustments to nominal diameter, working pressure rating, base material grade, coating material type, coating thickness (0.03–0.5mm), and sealing configuration. Customized solutions are also available for high-temperature or extreme corrosion environments. Please contact us with your technical specifications for a tailored quotation.