As shown in the illustration, a section of pipe with a 3.068 inch internal diameter, has a wall thickness of .216". When the pipe is bent into a 90° turn, the length of the outside edge of the curve "A-B" will exceed the length of the inside edge of the curve "C-D" by __________. See illustration GS-0108.
• Difference in arc length for a curve depends on angle in radians and the difference in radii • For any circle, arc length = radius × angle (in radians) • Relate pipe inside diameter, wall thickness, and outside diameter to find the radii of the inside and outside edges of the bend
• First, compute the outside diameter of the pipe from the given internal diameter and wall thickness; how does that relate to the spacing between the inside and outside edges of the bend? • For a 90° bend, convert the angle to radians and then multiply by the difference between the outside and inside radii. What simple value does that radius difference reduce to? • After you find the theoretical difference in arc length, compare your numerical result to the answer choices and see which one it matches most closely.
• Be sure you are using 90° = π/2 radians in the arc-length formula, not 90 • Confirm that the difference in radii between the outside and inside edges of the curve equals the pipe’s outside diameter, based on the geometry of the bend • Use enough decimal places for π and for your diameter values so that your final result clearly matches only one of the listed answers
No comments yet
Be the first to share your thoughts!