Which option correctly states the maximum slope allowed for two abutting plates in a joint?

• A. 1 in 20
• B. 1 in 50
• C. 1 in 30
• D. 1 in 25

Answer: (D)

Controlling how level the two abutting plates are along the joint keeps the weld geometry predictable and the root and throat accessible. A slope of 1 in 25 means the vertical difference between the plate surfaces cannot exceed one unit for every 25 units of joint length. Put differently, over a 25-inch length, the height difference should be no more than 1 inch; over 50 inches, no more than 2 inches, and so on. This shallow tilt helps ensure consistent heat input, proper fusion at the root, and a stable bead profile. Slopes steeper than this can make the root harder to weld reliably and can lead to misalignment issues or excessive distortion, while the 1 in 25 value provides the required tolerance for fit-up without sacrificing weld quality.