Welds between the vertical plates and the shell must be checked for combined vertical and horizontal loads. A 1/4-inch fillet weld is often sufficient, but larger bolts require detailed verification. Comparison: Chairs vs. Continuous Rings
The standard requires the chair to be designed to develop the full yield of the anchor bolt, ensuring the bolt stretches—rather than the chair or shell failing—during an overload event like an earthquake. Standardized Clearances: It provides specific formulas for emine sub m i n end-sub aisi e 1 volume ii part vii anchor bolt chairs better
(minimum eccentricity) to ensure heavy hex nuts can be tightened without interfering with the shell wall. Welds between the vertical plates and the shell
It prevents "prying" actions and reduces localized shell buckling by distributing the anchor bolt's eccentricity over a wider area of the shell. Continuous Rings The standard requires the chair to
The formulas are applicable to various structures, including flat-bottom tanks (API 650), conical shells, and tubular columns. Critical Design Considerations
Engineers using this manual must calculate several key dimensions to ensure the chair is "better" than a generic attachment: Chair Height (