Question

Which among the following is defined as percentage gap collapse when the ring closed to nominal cylinder diameter for 6 hrs at 350 degrees centigrade?

(a) Thermal set

(b) Pulse width

(c) Base pulse width

(d) Enthalpy

The question was posed to me in examination.

The above asked question is from Engine Components topic in chapter Basic Engine Components of Automotive Engine Design

Answer 1

Right choice is (a) Thermal set

For explanation I would say: The thermal set is defined ad the percentage gap collapses when the ring closed to nominal cylinder diameter for 6 hours at 350 degrees centigrade. The value thermal set for U1 is 12.5 it depends on the material used and the method used for casting.