A36 TANK SHELL 1/4 " THICK, M.D.M.T A36 TANK SHELL 1/4 " THICK, M.D.M.T stan000 (Mechanical) (OP) 19 Dec 17 16:53 A36 TANK SHELL 1/4 " THICK AS PER API 650 WHAT WILL BE Design Metal temp. I was looking chart 4.2.10 I understand for 0.250 thickness , GroupII IS -18°F Please advice. RE: A36 TANK SHELL 1/4 " THICK, M.D.M.T JStephen (Mechanical) 19 Dec 17 21:12 +10 degrees for straight A36, Group I. -18 degrees F for A36-Mod, Group II. Colder if Annex A design is used. Colder if qualified by impact testing- the temperatures above are the temperatures to be exempt from impact testing, but not limiting temperatures that can be used.