1. What is a high-pressure ball valve？
A high-pressure ball valve is a specialized quarter-turn control valve designed for high-pressure fluid systems (typically operating pressure ≥ 10 MPa, up to 100 MPa or higher). Its core component is a hollow or solid sphere with a through hole (bore) in the center. By rotating the sphere 90° via the valve stem, the bore aligns with or is perpendicular to the pipeline to control fluid on/off or flow regulation. It features excellent pressure resistance, tight sealing, and fast actuation, making it suitable for harsh high-pressure scenarios where leak prevention and reliable operation are critical.
2. Working Principle of High-Pressure Ball Valves
The operation of high-pressure ball valves relies on the "90° rotation of the sphere" to regulate fluid flow:
Open state: When the valve stem is rotated (manually or by an actuator), the sphere turns until its bore is fully aligned with the pipeline. Fluid flows smoothly through the bore with minimal flow resistance.
Closed state: Rotating the valve stem 90° further moves the sphere so that the solid part of the sphere blocks the pipeline. The high-pressure fluid presses the sphere tightly against the seals, creating a leak-tight seal—critical for preventing fluid leakage in high-pressure systems.
Sealing mechanism: For ultra-high pressure (≥ 35 MPa), metal-to-metal hard seals (e.g., stainless steel or alloy seals) are used to withstand pressure and avoid seal deformation; for medium-high pressure (10–35 MPa), elastic seals (e.g., PTFE or FFKM) are adopted for better sealing performance.
3. Structural Composition of High-Pressure Ball Valves
High-pressure ball valves consist of 5 core components, each optimized for pressure resistance:
Valve body: The main structural part, usually made of high-strength materials like 316L stainless steel, alloy steel (e.g., A105), or Hastelloy. It withstands high internal pressure and prevents deformation.
Sphere: The key flow-control component, machined from solid metal (e.g., stainless steel, Monel alloy) with high precision. Its surface is polished to reduce friction and ensure tight sealing.
Valve stem: Connects the actuator/handwheel to the sphere, transmitting rotational force. It is designed with anti-blowout structures to prevent ejection under high pressure.
Seals: Divided into seat seals and stem seals. Seat seals use metal or high-pressure-resistant elastomers; stem seals (e.g., graphite packing) prevent fluid leakage at the stem-pipe interface.
Actuator: Drives the valve stem rotation. Manual handwheels are used for small-diameter valves, while electric/pneumatic actuators are preferred for large-diameter or remote-control high-pressure systems.
4. Application Scenarios of High-Pressure Ball Valves
Oil & Gas Industry: Used in high-pressure wellheads, oil/gas transmission pipelines, and fracturing equipment to control crude oil or natural gas flow (resistant to 35–100 MPa pressure).
Hydrogen Energy Sector: Applied in 35/70 MPa hydrogen refueling stations and high-pressure hydrogen storage tanks, with anti-hydrogen embrittlement materials (e.g., 316L, Monel 400) to ensure safety.
High-Pressure Hydraulic Systems: Used in construction machinery (e.g., excavators) and industrial hydraulic presses to control high-pressure hydraulic oil flow.
Chemical Industry: Suitable for high-pressure reaction kettles and chemical reagent pipelines, with corrosion-resistant materials to handle acidic/alkaline fluids.
5. Precautions for Using High-Pressure Ball Valves
Material matching: Select valve materials based on fluid type (e.g., anti-corrosion alloys for corrosive fluids, anti-hydrogen embrittlement steel for hydrogen).
Regular inspection: Check seals and valve body integrity periodically; replace worn seals (e.g., PTFE seats) to avoid leakage.
Avoid overpressure/overtemperature: Operate within the rated pressure and temperature range to prevent valve damage or safety accidents.
Smooth operation: Rotate the valve stem slowly (especially for manual valves) to avoid sudden pressure shocks that damage the sphere or seals.
