13
Question Question 13
Give a reason why oiling or greasing is done on the exposed moving iron parts of machinery and not preferred on heavy stationary iron parts.
Oiling or greasing is done on the exposed moving iron parts of machinery as it forms a coating which protects it from rusting. It smoothens the surface and reduces friction in the machinery which is its added advantage.
Being stationary, for heavy iron parts, red lead oxide paint is used as there is no use of reducing the friction.