Ear shaft is an important component of mechanical support and is usually used as a fixed pivot point for rotating or oscillating structures. Its core functions can be summarized as support, connection, torque transmission, motion control, etc.. It is widely used in manufacturing, construction, aerospace and other industries. Here's a closer look:
I. Core Functions functions of neutron stars
Support and fixation
The trunnion is connected to the main structure by bearing or bushing, providing a stable support point for rotating components (e.g. valve ball, rotary furnace bodies, crane booms, etc.), ensuring balance during operation and preventing dislocation or vibration.
Torque and Load Transmission
In valves, the ear shaft transfers torque from the operating mechanism (such as the handle or pneumatic actuator) to the ball, allowing opening and closing.
In a rotary furnace or crane, the axle supports the weight and work load of the equipment, transferring the force to the supporting structure (such as a bearing housing or foundation).
Movement path control
The fixed position of the shaft neck determines the range of motion of the rotating components (for example, the 90-degree rotation of the valve ball, the tilting angle of the converter), ensuring precise and controlled operation.
Reduced Friction and wear
Through bearing or lubrication design, the trunnion friction between rotating components and supporting structure is reduced and the service life of equipment is extended.
ii. Typical application of Trunnion
Valve industry
Fixed-ball valve: The trunnion holds the ball in position; the seat seals the ball with spring or fluid pressure and is suitable for high pressure, large diameter applications (e.g., oil pipelines).
Floating ball valve: The ball is connected to the valve stem through the trunnion; fluid pressure pushes the ball toward the seat for sealing, suitable for low to medium pressure situations such as water supply systems.
Metallurgical Industry
Rotary furnace trunnion: Supports the main body of the converter, can tilt material loading and attack steel during steelmaking; must be able to withstand high temperature, heavy load and frequent start and stop.
Aerospace
Rocket engine nozzle trunnion: Control of nozzle oscillation, adjustment of thrust direction, for spacecraft attitude control; requires high accuracy and high temperature resistance. Construction Machinery
Crane Swivel Bearing: connect the boom to the rotary platform, transfer lifting loads, control the boom's pitch angle, high strength, fatigue resistance.
Energy Equipment
Wind Turbine Yaw System Swivel Bearing: support the nacelle and control its horizontal rotation to ensure that the blades are always aligned with the wind direction for optimal power generation efficiency.
III. Design Key Points of Swivel Bearings
Material Selection
High strength materials (e.g. alloy steel, stainless steel) are selected according to conditions of use, and corrosion resistance (e.g. anticorrosive coatings for chemical industry) and high temperature resistance (e.g., heat-resistant alloys) are considered.
Structural Optimization
Finite Element Analysis (FEA is used to optimize the shape of rotary bearings, reduce stress concentration and improve fatigue life.
Use hollow structures or light holes to reduce weight (e.g. in aerospace applications).
Lubrication and sealing
Design lubrication channels or use of self-lubricating bearings to reduce friction;
Install sealing devices (e.g., O-rings, labyrinth seals) to prevent liquid leakage or contamination.
Installation and maintenance
The gap between the rotary bearing and the supporting structure is strictly controlled to prevent loosening.
Periodically check bearing wear, lubrication status and sealing performance, and replace damaged parts in a timely manner.
IV. INTRODUCTION Differences between Swivel Bearings and Similar Components
Typical application of component key function
Rotating bearings support rotating parts and transmit torque valves, rotary kilns, cranes
Hinges connect two parts, allowing relative rotational door, window, and robotic arm joints
Pins provide fixed connection and transfer of axial force
Shaft supports rotating parts and conveys torque motors and gearboxes
Key differences: Swivel bearings, usually used with bearings, emphasize stability and torque transmission; hinges focus on flexible rotation; pins primarily provide fixed connections; and axles prioritize torque transmission efficiency.
