Different Types of Rod End Bearings and Their Maintenance Records

Rod ends are plain, spherical, tapered, axial, or linear bearing units, which are used to attach a rotating shaft to a shaft or crankcase. They consist of a housing and central shank, to which a flat or internally threaded external thread is added, and also contain either an internal or external spiral thread drive. All of these factors combine to provide a high degree of tolerance to a wide range of operating conditions. They are often made using materials that are robust and durable, which make them suitable for use in a wide variety of applications. Two types of rod ends exist:

Rod end types that incorporate low-profile profiles and smooth, low-profile performance are called low-profile rod ends. These are available in both closed-end and open-end configurations. Closed-end rod ends normally feature a straight, tapered, counter-rotating, or pendulum-coupled shank. The open end is commonly referred to as a 'wedge' by industry and users. These types of rod ends offer the greatest compatibility with other types of mating systems, which allows for the installation of various different cams and flange nuts, screws, nipples, seals, etc. In addition, this type of end features many advantages over conventional high-performance materials such as aluminum, gold, brass, steel, and nickel.


The former din refers to spherical plain bearings Din, previously referred to as roller bearings. Spherical plain bearings have been used in industries and manufacturing for decades, however, before this time, they were typically fabricated using a male threading bolt that was installed on a female thread rod. This was problematic because the male threads often wore out and fell out, which could cause catastrophic damage to equipment or machinery. In addition, the female threads, which are usually supplied by the manufacturer, were subject to wearing out faster and sometimes had to be replaced altogether.

Rod End fittings that are designed to handle large loads are often fabricated with a series of spherical plain bearings. Although they offer superior load bearing abilities, they also provide unique wear and tear characteristics that are not common to the other rod ends on the market. For instance, the spherical plain bearings of series k series e series can withstand very heavy loads, but are susceptible to corrosion and grinding if used in corrosive environments. Furthermore, the small round center hole on the female threading side of the bolt can become clogged with grease over time, reducing the load bearing capabilities of the assembly.

Rod Ends come in a variety of materials including, but not limited to brass, steel, aluminum, stainless steel, titanium, and many other alloys. Furthermore, these materials can be built with a variety of different mechanical and chemical sealants. However, the most popular type of rod end, especially in today's market, is cast iron. In fact, this particular design has been used for over one hundred years. Unfortunately, the popularity of this design is quickly fading as it experiences the same problems as other metals that experience a decrease in their tensile strength when stressed to excessive loading or in corrosive environments.

Rod ends come in a variety of different threading arrangements. Most commonly, they are manufactured using two threading assemblies, either a thin rod section or a swivel joint, which allow for the addition of various locking diodes. Additionally, there are a few different designs that have been used to make them maintenance-free. The limited fitting dimensions of many of the threaded rod ends have made them unable to handle extremely high loads.

Most rod ends on the market are either solid or spherical in shape. However, as previously stated, they have been unable to withstand very heavy loads and must be properly sized for each application where they will be used. For example, the small round spherical bearings are able to work fine in small to medium sized applications while the large solid rubber wheels may need to be used with extremely heavy loads. Even when they are properly sized, there is still the issue of corrosion resistance. Consequentially, these bearings are often corrosive environments and require maintenance.

Limited bearing design features can also affect the cost of the end products. In most cases, they are offered with either a tapered or non-tapered sleeve, which determine the level of wear and tear that occurs over time. In addition to being worn down over time, these tapered sleeves are often unable to handle extremely high loads, resulting in lubrication loss and excessive friction levels. Typically, the most expensive end bearing design is the solid spherical bearing, which is usually the most reliable and maintenance-free as well.