Oilers/Plant Tenders (HHC) Civil Service Practice Exam

What is the typical use of babbitt metal in machinery?

1. Welding

2. Electrical wiring

3. Bearing surfaces

4. Fuel tanks

The correct answer is: Bearing surfaces

Babbitt metal is primarily utilized as a bearing material, which is why the answer is C. This alloy, developed for its low friction characteristics, is typically used in the formation of bearing surfaces in machinery. Babbitt metal is known for its ability to conform to the shaft and to provide a protective layer that reduces wear, extends the lifespan of the components, and minimizes vibration and noise. The material is specifically engineered to accommodate the dynamic loads and movements present in machinery, allowing for smooth operation. Its low coefficient of friction is essential in reducing energy loss and heat generation in applications involving rotating shafts. Other choices do not fit the typical applications of babbitt metal. For instance, welding is a process used to join metal pieces together, which is unrelated to the properties of babbitt. Similarly, electrical wiring is crucial for conveying electrical power and signals but does not involve babbitt, as its properties would not serve this purpose. Fuel tanks require materials that can withstand chemical corrosion, which does not align with the standard characteristics of babbitt metal. Thus, the correct response reflects the primary and most appropriate use of babbitt in the context of machinery operation.