Question 679Steam Plants - Assistant Engineer

The correct answer is A) peening the tenons. Impulse turbine blades are held in place by peening the tenons, which are the projections at the base of the blades that fit into the rotor disc. Peening refers to the process of hammering or rolling the metal to deform it and lock the tenons in place. This is a common method used to secure turbine blades and prevent them from becoming dislodged during operation. The other answer choices are incorrect because: B) circumferential dovetails are used to secure reaction turbine blades, not impulse turbine blades; C) seal welding is not a typical method for securing impulse turbine blades; and D) locking keys are not commonly used to hold impulse turbine blades in place.