Babbitting is a metal alloy coating that goes on a base metal to protect it from wear. Typically, the Babbitting process is used on investment castings, which are made of cast iron. The challenge is that investment casting is costly to produce. The Babbitting process helps to protect the bearing surface of the casting giving it an extended life span. In addition, the cost to replace or repair the casting wear surface is significantly less.
Named after Isaac Babbitt, the patented Babbitting process has been used throughout North America for more than 150 years. Compared to white metals, Babbitt metals are more widely known. These metals primarily consist of tin alloys that are hardened with antimony, copper, and lead alloys that are hardened with antimony and tin. In some instances, lead alloys also contain arsenic.
As part of the Babbitting process, the relatively soft bearing material bonds to a much stronger base metal, giving it support. The exact form can be a half-round mild steel bushing or pressing, an iron or bronze casting, or a mild strip of steel unwound from a coil.
Babbitts are used for many different purposes. For example, they are used to make plain and fluid film lubricated bearings for various industries, including marine, automotive, and industrial. The bonded bimetal material is shaped and then machined. This is accomplished by metal spraying, hand bonding, or casting. Of the different methods used, hand bonding is the most reliable as far as adhesion to the base material.
Babbitting is used for many applications, including electric motors and internal combustion engines. It is beneficial in small bearings, as well as large reciprocating and rotating machinery that require low to modest volumes, such as high-speed turbines and low-speed diesel engines. Depending on the final application, several different metals ranging from high Lead to high Tin content are used for babbitting. If you are unsure which Babbitt is the right one for your needs, contact us today and our representative can help you decide based on the given application.
The bottom line is that babbitting is a more cost-efficient method of maintaining a bearing surface on a high-dollar investment casting. Because precision is so important, you always want to rely on a respected and trusted source. At Canada Metal North America (CMNA), we use the hand bonding babbitting method and guarantee a minimum of 85 percent bond. We offer babbitting services in situ or at our facilities in Montreal and Ontario. Contact us today to learn more.