API 650 petroleum storage tanks special considerations

The heat transfer oil fin tube heating device for large API 650 petroleum storage tanks heats the circulating heat transfer oil in the shell and tube heat exchanger through high temperature and high pressure steam. The heat transfer oil exchanges heat with the medium to be heated in the storage tank through the heating coil, so as to heat the storage medium. High temperature heat transfer oil fin tube heating device has the following advantages:
1. High heat transfer efficiency
2. Reduce heating coil leakage
3. Easy to repair and maintain

Preheating should be performed by heating and maintaining this heat in appreciable lengths of the joint to be welded, preferably using a strip burner with a mild flame rather than a harsh flame such as that from a cutting torch. Electrical strip heaters are available and have been found to be satisfactory. The preheat of 300°F should be checked with a temperature-sensitive crayon, or similarly accurate means, so that the steel 4 in. (or four times the API 650 petroleum storage tanks plate thickness, whichever is greater) on each side of the joint will be maintained at the minimum preheat temperature. Ring burners or heaters are recommended for nozzle and manway welds. At no time during the welding should the base metal fall below a temperature of 300°F.

Upon completion of API 650 petroleum storage tanks construction, provide Purchase with a Vendor's Certification that the tank conforms to the requirements of API 650 and to the additional requirements as specified.