API 650 Clause 5.12.10- Thermal Expansion of Tank

[NVSKumar]

Storage Tank Designed as per API 650, 12th ED. March 2013,(Annex. E, F, M, P & V) , operating at 180°C. As per API 650, Annex. M was considered for Design as Maximum Design Temperature was exceeding 93 deg.C

My query is,
In the Clause 5.12.10 of API 650 which states as in quotes “When specified by the Purchaser, the anchors shall be designed to allow for thermal expansion of the tank resulting from a temperature greater than 93 °C (200 °F)”.
what is the intend of this clause and how to accommodate thermal expansion in Anchors, does providing SLOTTED holes in the Anchor Chair Top Compression Plate resolve this problem or is there any other method to accommodate thermal expansion in Anchors?

Please guide me.

 

[IFRs]

You would need to have enough of a gap between the outer edge of the bottom plate under the shell and the anchor to accommodate the thermal growth of the tank, with some safety margin. You need to design the anchorage above the bottom plate to not itself become overstressed from combined tension and bending and the tank connection to not over stress the tank shell under the various load combinations. Use your imagination and analytic skills along with your engineering expertise. Anchors are not always round rod.