Question 149Steam Plants - Assistant Engineer

The correct answer is A) prevent steam from entering the soot blower when the element holes are directed toward the refractory. The cam-actuated steam valve in a boiler soot blower system is designed to control the flow of steam to the soot blower element. When the element is positioned towards the refractory, the cam-actuated valve will close to prevent steam from entering the soot blower. This is a safety feature to avoid damage to the refractory when the soot blower element is not in the proper blowing position. The other answer choices are incorrect because they do not accurately describe the primary purpose of the cam-actuated steam valve, which is to prevent steam from entering the soot blower when the element is not properly positioned.