In structural boiler riveting, what reference basis is used for shear, bearing, and tensile stress calculations_________________?
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Answer: B. size of the drilled or reamed hole
Explanation
In boiler riveting calculations, stresses are based on the diameter of the drilled or reamed hole rather than the nominal rivet size. During manufacturing, rivets expand to fill the hole completely, making the finished hole diameter the correct reference size. Using hole dimensions ensures accurate calculation of net plate areas and shear stress resistance. Boiler construction codes mandate strict geometrical standards for rivet hole spacing, edge distances, and diameters. Hole diameters are slightly larger than nominal uncompressed rivet sizes to facilitate assembly insertion. Stress calculations must account for the actual material removed during the drilling and reaming process.
Nominal rivet size before driving is smaller than the finished hole and does not reflect actual material removal. Averaging rivet and hole sizes introduces calculation errors that violate standard pressure vessel design codes. Stating any one of the above is incorrect because engineering codes mandate using the drilled hole size.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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