WIND GIRDERS IN A CONE ROOF WIND GIRDERS IN A CONE ROOF jor1492 (Mechanical) (OP) 24 Aug 15 16:47 Hello Is it necessary a top wind girder and secondary wind girder for a cone roof tank with 7m of diameter and height of 11 m ? Or Are the wind girders only for open roof tanks ? RE: WIND GIRDERS IN A CONE ROOF JStephen (Mechanical) 24 Aug 15 17:40 The top wind girder is only for open top tanks. Stability of the top of the shell is furnished by the roof otherwise. An intermediate wind girder is used if needed on either type, and omitted if not needed on either type. In a lot of cases, it is more economical to thicken the shell slightly if required than to install an intermediate wind girder. RE: WIND GIRDERS IN A CONE ROOF jor1492 (Mechanical) (OP) 24 Aug 15 18:51 Thank you JStephen for the good answer. I have another question. Does the attach ,of the body with the roof, required the use of a Angle beam?, and the function of that Angle beam is only for the attach or does it have another function? RE: WIND GIRDERS IN A CONE ROOF fegenbush (Mechanical) 25 Aug 15 01:17 Yes, a top angle is required per 18.104.22.168.e of API 650 unless the roof is flanged. This is provided for stability of the top shell course during erection. RE: WIND GIRDERS IN A CONE ROOF JStephen (Mechanical) 25 Aug 15 02:26 API doesn't really say what the purpose of the top angle is- keeping the shell round during roof erection is what I supposed. In the current API-650, you're allowed to omit the top angle if the area furnished in that region matches that obtained with a top angle- see the wording in the top angle specification. One other thing, I said the roof furnishes stability for the top of the shell- that's assuming a steel roof, an aluminum dome would still use a wind girder. RE: WIND GIRDERS IN A CONE ROOF jor1492 (Mechanical) (OP) 25 Aug 15 14:19 Thanks fegenbush and JStephen , by answer my questions RE: WIND GIRDERS IN A CONE ROOF lps123 (Mechanical) 5 Sep 15 03:36 Hi Can some one advice do you have to consider tank over turning moment due to internal pressure when calculating seismic over turning moment in API650 Annex-E ?