Question

In a situation where water passes through a bearing, the preferred material for bearing is:

• A. Lignum vitae
• B. Cast iron
• C. Babbit
• D. Teflon

Hint:

Lignum vitae is preferred for water-lubricated bearings due to its natural lubricating and wear-resistant properties.

Answer 1

The Correct Option is A

1. Introduction to Bearing Materials:
Bearings are used to reduce friction between moving parts in machinery. The material of a bearing plays a crucial role in its performance, particularly in terms of load capacity, wear resistance, and friction reduction. 2. Role of Material in Water-Lubricated Bearings:
For systems where water is used as a lubricant, the material should be able to handle both the lubrication provided by water and the wear caused by the relative motion between the parts. 3. Why Lignum Vitae:
Lignum vitae is a very dense and oily wood with natural lubricating properties. It has historically been used in water-lubricated bearings, particularly in applications where water is present as a natural lubricant (e.g., marine applications). It offers low friction, good wear resistance, and is well-suited for water-lubricated systems. 4. Why Not Other Materials:
Cast iron (Option 2) is durable but brittle, and water can cause rust and corrosion in cast iron bearings.
Babbit (Option 3), while excellent for general bearing applications, is not ideal for water-lubricated conditions.
Teflon (Option 4) is used in low-friction applications but is not commonly employed in bearings exposed to water due to its lack of sufficient strength and wear resistance for heavy-duty use.