What are the installation slopes of double layered storage tanks?

As a supplier of double layered storage tanks, I've witnessed firsthand the importance of proper installation, especially when it comes to the installation slopes. These slopes play a crucial role in the functionality, safety, and longevity of the tanks. In this blog post, I'll delve into the details of installation slopes for double layered storage tanks, explaining why they matter and what the optimal slopes are.

Why Installation Slopes Matter

1. Drainage

One of the primary reasons for having an installation slope is drainage. Double layered storage tanks are often used to store liquids such as oil, fuel, or chemicals. Over time, water can accumulate inside the tank, either through condensation or from the stored liquid itself. If this water is not drained properly, it can lead to corrosion, which can compromise the integrity of the tank. By having a proper slope, water and other sediments can flow towards a drain or a low - point where they can be easily removed.

2. Preventing Siphoning

A correct installation slope helps prevent siphoning. Siphoning can occur when there is a difference in liquid levels between two connected parts of the tank system, causing the liquid to flow in an unwanted direction. This can lead to spills, leaks, and inaccurate level measurements. The slope ensures that the liquid flows in a controlled manner and reduces the risk of siphoning.

3. Even Distribution of Load

The weight of the stored liquid and the tank itself needs to be evenly distributed on the foundation. A proper slope helps in achieving this even distribution. Uneven load distribution can cause stress concentration in certain areas of the tank and its foundation, which may lead to structural damage over time.

Optimal Installation Slopes

General Guidelines

The optimal installation slope for double layered storage tanks typically ranges from 1:50 to 1:100. This means that for every 50 to 100 units of horizontal distance, there is a 1 - unit drop in vertical height. For example, if the tank has a diameter of 10 meters (1000 centimeters), with a 1:100 slope, the difference in height from one side of the tank to the other should be 10 centimeters.

Specific Considerations

• Type of Liquid Stored: Different liquids have different viscosities and densities. For example, storing a highly viscous liquid like heavy fuel oil may require a steeper slope compared to a less viscous liquid like gasoline. This is because the more viscous the liquid, the more difficult it is for it to flow towards the drain.
• Tank Size and Shape: Larger tanks may require a more precise slope to ensure proper drainage across the entire surface. Similarly, tanks with irregular shapes may need special attention to ensure that all areas of the tank are properly sloped.

Installation Process

Foundation Preparation

Before installing the double layered storage tank, the foundation must be prepared. The foundation should be leveled initially and then sloped according to the required specifications. This may involve using a laser level or other precision measuring tools to ensure accuracy.

Tank Placement

Once the foundation is ready, the tank is carefully placed on it. During placement, it's essential to ensure that the tank aligns with the slope of the foundation. Any misalignment can lead to improper drainage and other issues.

Verification

After the tank is installed, the slope needs to be verified. This can be done using a spirit level or other measuring devices. If the slope is not within the acceptable range, adjustments may need to be made.

Case Studies

Case 1: Gasoline Storage

We installed a Double Layered Steel Oil Tank for a gasoline storage facility. The tank had a diameter of 8 meters and was installed with a 1:80 slope. After a year of operation, we conducted an inspection and found that the tank had excellent drainage, with no signs of water accumulation or corrosion.

Case 2: Chemical Storage

A client needed to store a corrosive chemical in a Two - compartment Oil Tank. Due to the nature of the chemical, we recommended a steeper slope of 1:60. The tank was installed accordingly, and since then, there have been no issues with siphoning or uneven load distribution.

Maintenance and Monitoring

Regular Inspections

Regular inspections of the tank's slope are essential. Over time, the foundation may settle or shift, which can affect the slope. Inspections should be carried out at least once a year, or more frequently in areas with high seismic activity or unstable soil conditions.

Monitoring Equipment

Installing monitoring equipment such as level sensors and inclinometers can help in continuously monitoring the slope and the liquid level inside the tank. This data can be used to detect any changes in the slope or potential issues early on.

Conclusion

In conclusion, the installation slopes of double layered storage tanks are a critical aspect of their installation and operation. Proper slopes ensure efficient drainage, prevent siphoning, and even load distribution. By following the general guidelines and considering specific factors such as the type of liquid stored and the tank size and shape, we can ensure the optimal performance and longevity of the tanks.

If you're in the market for double layered storage tanks and need expert advice on installation slopes or any other aspect of tank installation and operation, we're here to help. Our team of experienced professionals can provide you with customized solutions based on your specific requirements. Contact us today to start a discussion about your storage needs and how we can assist you in making the right choice.

References

• API 650 - Welded Steel Tanks for Oil Storage. American Petroleum Institute.
• BS EN 14216 - Glass - reinforced plastics - Underground and above - ground storage tanks and vessels for the storage of liquid chemicals at ambient temperature. British Standards Institution.