API standard 650 special tank roof configuration

Aftershock Level Earthquake (ALE)
This design case shall be applicable only when regulations or project documents specifically require the tank system to be designed or evaluated for aftershocks.
If the outer tank is not designed as a secondary containment (i.e. it serves as vapor barrier and pressure boundary only and is not constructed of API 620 material suitable for the inner tank API standard 650 special tank), then no design or evaluation for ALE is required by these provisions for the inner or outer tank.

API 650 tank has the advantages of less load on the floating plate, simple and light structure, and can save the central drainage pipe and rotating floating ladder on the API standard 650 special tank floating plate. The materials for easy construction and maintenance and sealing parts can avoid aging due to sunlight.

In the year of 2015, customer from Peru oil refinery contact with us from Internet. After one month’s negotiation and quotation, they chose us as there supplier of raw steel plate API standard 650 special tank grade ASTM A36. We get an trail order of 300 tons in April. When the first ship arrived, they inspect the steel plate and very happy with the quality we supply. Then they put another 1700 tons order, we sent to them within 90 days. Our company management group visit the customer in the beginning of 2016 and the visit is very successful.

Inspection of weld and micro crack of API standard 650 special tank: the inner and outer surface of API standard 650 special tank, weld and heat affected zone shall be observed by naked eyes first. 100% ultrasonic testing or 100% penetrant testing are carried out for butt welds of API standard 650 special tank. For the defects found by 100% magnetic particle inspection, dye detection, 100% ultrasonic inspection or 100% penetrant inspection, the radiographic inspection shall be used again to ensure the accuracy of the test results.

The company has passed the ISO9001: 2008 quality system certification, strictly implemented the ISO9001 quality management system. Besides, we have continuously improved the after-sales service network to make every effort to provide more convenient, accurate and faster services for all customers. We will supervise the production, control the quality in the factory, Inspect the cargo before shipment, Issue the test report to sales department. From the steel prodcution to steel delivery, we always focus the whole process.