This specification covers material@ design@ and construction requirements for vertical@ cylindrical@ above-ground@ shop-welded@ steel production tanks in nominal capacities of 90 to 400 bbl. (in standard sizes up to a maximum diameter of 12 ft.) for oil-field service. Nothing contained in this specification is to be construed as granting any right@ by implication or otherwise@ for manufacture@ sale@ or use in connection with any method@ apparatus@ or product covered by letters patent@ nor as insuring anyone against liability for infringement of letters Patent.