This specification rovers material@ design@ fabrication@ and erection requirements for vertical@ cylindrical@ above-ground@ welded-steel@ production tanks in nominal capacities of 500 to 3@000 bbl (in standard sizes) for oil-field service. 2. 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.