Rod ends are a commonly used on linkages, pneumatic or hydraulic cylinders and adjustment arms. The bearing element consists of a spherical ball with a central through bore encapsulated in an outer ring. The spherical ball, or eye, has rotational freedom and some additional inclination of the bore. Viewed from the though bore this corresponds to roll and small amount in pitch and yaw. This construction allows for misalignment and changes of angular alignment during motion.
Being a plain bearing care must be taken in high speed or cycling applications and they are not suitable as a rotary bearing. In practice this is a minor limitation and they are widely used in industry. Types of plain spherical construction are available but by far the most popular types have a body preformed with a male or female thread for attaching directly to rods, linkages or actuators.
In smaller types the outer ring is formed from the rod end body, usually have a bronze liner between the ball and outer ring and can be lubricated. Larger types often of steel on steel construction where both the ball and outer ring is made from bearing steel and press fit into the outer body. Maintenance free types with a Teflon liner are also available.
One of our most popular types have a fine pitched thread with a stainless body and Teflon liner which are widely used directly attached to pneumatic cylinders. Another popular type features a male thread extending from the ball in place of the through ball. This type is know as a ball joint and is similar to the control joints on vehicle suspension.