Air Storage Tank Installation and Pipeline Connection

In industrial gas systems, air storage tanks are crucial for gas storage. The proper installation and pipeline connection of these tanks are vital for the system's stability and safety. This article outlines the installation steps, pipeline connection requirements, and key considerations to ensure efficient and reliable system operation of air storage tanks.

Air Storage Tank Installation

The installation of an air storage tank involves several steps, including equipment preparation, lifting, and securing the tank. The process begins with checking the stability of the concrete foundation to ensure it meets the required specifications. Next, the tank is securely tied with steel ropes and lifted into place using a crane. Once positioned correctly, the tank is anchored with expansion bolts to ensure its stability.

1. Preparation Before Installation

Before starting the installation of the air storage tank, the compressor and tank equipment must be checked and prepared. Key steps include:
Foundation Check: Inspect the concrete foundation for levelness and firmness, ensuring it meets design specifications. The foundation should have sufficient load-bearing capacity to support the tank's weight and potential vibrations.
Lifting Preparation: Secure the equipment using steel ropes to ensure stability during the lifting process. Choose an appropriate crane, and handle the equipment carefully to avoid any damage.

2. Lifting and Securing the Tank

The crane lifts the air storage tank and positions it accurately on the concrete foundation. The tank must be securely anchored using expansion bolts to prevent any shifting or tilting during operation. The bolts must be tightened to the specified torque to ensure stability.

Compressed Air Pipeline Installation

After the air storage tank is in place, the next step is installing the compressed air pipeline. This involves marking and cutting the pipes according to the site measurements, removing burrs from the pipe ends to ensure smooth connections, and performing beveling and welding to secure proper alignment and a solid connection. Once welding is completed, the welds must be inspected for defects, and flanged connections should be made to ensure tight seals and a reliable pipeline system.

1. Pipe Preparation and Cutting

Before installation, measure and mark the pipes based on site measurements, and then cut the pipes. There are two common cutting methods:
Grinding Method: Secure the pipe in a grinding clamp, apply even pressure during cutting, and remove any burrs or metal shavings after cutting to prevent interference with welding.
Hand Sawing: Secure the pipe in a clamp and cut with a hand saw. The saw blade should be perpendicular to the pipe axis, and the force should be evenly applied to ensure clean, un-deformed cuts.

2. Welding and Connections

Beveling: Before welding, bevel the pipe ends using mechanical planing or oxy-acetylene cutting. After beveling, remove any oxidation and ensure the surfaces are smooth for optimal weld quality.
Welding: Align the pipes properly, and use tack welding to hold the ends together. For pipes with a diameter of 100mm or less, tack weld at three points; for pipes with a diameter over 150mm, weld four points. After tack welding, ensure the pipe ends are precisely aligned. The welded joints should be inspected for cracks, pores, slag inclusion, or other defects. The welding width should not exceed 2mm, depth should not exceed 0.5mm, and the weld length should not exceed 25mm. Any defects must be cleaned and re-welded.

3. Flange Connections

Flange Welding: Insert the pipe into the flange, tack weld 2-3 points, and adjust the pipe position with a square before welding. The flange should be welded on both sides, ensuring the internal weld does not protrude from the sealing surface.
Flange Tightening: Use PTFE gaskets between flanges, ensuring tight connections. Bolts should have washers, and the exposed part of the bolt should not exceed half of its diameter.

Air Storage Station Process Flow and Considerations

Once the compressed air pipeline is installed, the next step is designing the process flow and considering key aspects for the air storage station. The main task of the station is to ensure correct connection between the air storage tank and the pipeline system, facilitating smooth switching between high and medium pressures. Additional considerations include cathodic protection, CNC refueling station location, and pipeline layout to ensure overall system safety and efficiency.

1. Pressure and Tank Connection

The design of the air storage station should avoid excessive entry pressure to prevent errors in connecting the tank system's pipeline. Specific requirements are as follows:
The tank should be connected between high and medium pressure manifolds for easy switching between pressure areas.
High-pressure connections are used for storage, ensuring sufficient gas reserves, while medium-pressure connections supply the gas for system operation.

2. Cathodic Protection System Application

Cathodic protection plays a significant role in preventing corrosion in gas pipelines. However, its application must account for the surrounding environment and the pipe materials to avoid adverse effects on other metal structures. A thorough evaluation should be conducted when installing cathodic protection, balancing its advantages and disadvantages.

3. CNC Refueling Station Location

To maximize natural gas pressure resources and reduce electricity consumption, CNC refueling stations should ideally be connected to high-pressure pipelines. This reduces investment and operational costs for compressors while improving overall system efficiency.

4. Tank Configuration in the System

In some gas projects, particularly in urban areas with limited space, a high-medium pressure dual-stage solution is often used. For example, the air storage tank may be positioned at one end of the city with a corresponding storage station at the opposite end. This setup utilizes the high-pressure pipeline efficiently while allowing for parallel medium-pressure pipelines.

5. Pipeline Layout and Standards

Pipelines rated at 1.6MPa should not be laid on busy city roads. Although regulations for town gas design have relaxed regarding 1.6MPa pipelines, stricter quality control is needed. In densely populated areas, more rigorous standards and measures should be implemented during the design and construction phases to ensure pipeline safety.

Conclusion

The installation of air storage tanks and pipeline connections is a critical part of gas systems, directly affecting the stability and safety of the system. By following proper installation procedures and adhering to technical requirements, efficient and safe operation can be ensured. During installation, it is essential to strictly follow design specifications to prevent errors or damage due to improper procedures. Air storage station design should consider equipment selection, pipeline layout, and process optimization to ensure the system operates efficiently and reliably.