Question 67 CEL01 - Chief Engineer - Limited

The Correct Answer is D **Explanation for Option D (2 1/2 inches):** Option D, 2 1/2 inches, is the correct length for the stud used to secure the packing gland in Illustration GS-0012. Studs used for packing glands must be long enough to pass through the main body flange or housing, traverse the entire thickness of the gland follower (or 'lantern ring'), and allow sufficient thread engagement for the nut used to compress the packing material. A length of 2 1/2 inches is a standard dimension that provides the necessary clearance and mechanical advantage for proper tightening and adjustment of the packing gland without running out of threads or compromising the integrity of the seal. **Explanation for Incorrect Options:** * **A) 1 inch:** This length is significantly too short. A 1-inch stud would likely not be long enough to span the distance required—including the thickness of the housing, the gland follower, and the height of the securing nut—to properly compress the packing material. * **B) 1 1/4 inches:** This option is also too short. While longer than 1 inch, 1 1/4 inches generally does not provide enough length to accommodate both the component thicknesses and adequate thread engagement for a secure and adjustable seal assembly. * **C) 1 1/2 inches:** This length is often considered marginal for packing gland assemblies. While it might fit on extremely thin applications, it typically does not provide the required protrusion past the nut (1 to 2 threads) needed for mechanical stability and reliable adjustment of the gland compression illustrated in standard engineering diagrams like GS-0012.