API 650 aboveground oil storage tanks testing of the roof

Preheat Treatment
Many laboratory tests have shown preheat treatment of carbon steel to 300°F-400°F to be the equivalent of the post-heat treatment at no less than 1100°F insofar as the physical properties of the weldment are concerned.40,41 Some tests have indicated a slight advantage of the post-heat treatment. Most of the tests have been made on plates 3/4 in. - 1 in. thick; results must be viewed with caution if preheating is applied appreciably beyond this thickness range. However, for all practical purposes, improvement resulting from preheating is sufficiently well established so that preheat should be considered for field fabrication of API 620 crude oil tank plates over 3/4-in. thick whenever toughness of the tank API 650 aboveground oil storage tanks is highly desired and the thermal post-heat treatment is impractical.Fixed roof API 650 oil storage tank includes inner floating roof tank, which API 650 aboveground oil storage tanks can effectively prevent sand, rain, snow or dust from polluting the storage liquid. Under various weather conditions, API 650 oil storage tank can ensure the quality of liquid storage, which is called "all-weather API 650 aboveground oil storage tanks storage tank".In year 2015, we ship 750 tons H beam to Pakistan for our old customer for building use. Because of urgent demand, the H beams are partial shipment by bulk vessel. Due to strong support of our customer, we also export many C channel steel, API 650 aboveground oil storage tanks I beam and other profile steel to local market.Requirements for prefabrication of bottom plate of large vertical API 650 aboveground oil storage tanks:
1. The diameter of tank bottom should be enlarged by 0.1% ~ 0.15% according to the design diameter.
2. The minimum dimension of edge plate along the radius direction of tank bottom shall not be less than 700mm.
3. The distance between any adjacent welds of the base plate shall not be less than 300 mm.The 365 day service system is implemented, and the business, loading and delivery are handled as usual in holidays and festivals. Actively help users solve difficulties. When users encounter difficulties in handling business, they should actively coordinate with the external solution; if they need to solve the problems internally, they should solve them in a timely manner without prevarication and wrangling. In line with the API 650 aboveground oil storage tanks principle of "fairness, justice and timeliness", coordinate with relevant departments and deal with all kinds of objections in a timely manner.