BABBITT METAL


| November/December 1968



410 Hamilton St.,Washington, Ill. 61571

You have used it, and poured it into a journal-box. Have you ever wondered about what you were working with? Where did it get its name? What is it? What is a journal-box? Wellits a bearing to you; in this case a babbitted bearing. Steam engines, threshing machines and other old farm machines were full of it; you have nursed it and cursed it.

A journal bearing consists of two machine parts that rotate relatively to each other. The part which enclosed by and rubs against the other is called the JOURNAL (shaft of axel) and the part which encloses the journal is called the BOX or less specifically the BEARING. In the more common form of journal bearings, the journal rotates inside of a fixed bearing. In some cases, as in a loose pulley, the journal is fixed and the bearing rotates, while in other cases both the journal and the bearing have a definite motion, as for example, a crank pin and its bearing in the connecting rod.

Did you know that the 'inventor' of babbitt metal for bearings did not conside it important and did not have it patented? But he did go on and get a patent on the JOURNAL-BOX'.

Babbitt metal is one of our most important bearing metals today. The modern automobile you drive today depends on it. Babbitt metal is an alloy of tin or lead. It is classed as a white metal. Even white brass is in reality a babbitt metal. Other ingredients may be copper, antimony, nickel, phosphor bronze, silver, zinc, cadmium, and more. It has excellent anti-friction and corrosion resistance properties which set a standard for all bearing metals.

The alloy containing copper, tin and antimony is usually called GENUINE BABBITT METAL. According to the Society of Automobile Engineers, at one time, the following specifications will produce a high grade of babbitt that should give excellent results when used for such service as connecting-rod bearings, or any other machine bearings subjected to similar service: copper, 7%, antimony 9%, tin 84%. There are a large number of commercial grades of babbitt metals, many of which have a high percentage of lead and consequently sell at a low price.