Question 439Steam Plants - Assistant Engineer

The correct answer is C) 3. According to the illustration SG-0003, item number 3 represents the "standard fire brick" that lines the rear wall of a typical boiler furnace. Fire brick is a specialized high-heat resistant material used to line the interior of boilers and furnaces to withstand the extreme temperatures. This is the standard construction for boiler furnace walls as per industry regulations and best practices. The other answer choices do not correctly identify the fire brick lining. Options A, B, and D represent different components of the boiler furnace, such as the casing, insulation, and soot blower, but do not depict the fire brick that is the focus of this question.