A directly buried bellows compensator is a device specifically designed for use in underground pipeline systems, which is capable of absorbing pipeline displacements due to temperature changes, foundation settlement, and other mechanical stresses. This type of compensator is especially suitable for long-distance conveying pipelines in industries such as thermal pipelines, water supply and drainage pipelines, and petrochemical industries that need to be buried directly in the soil. The following are the main features, structural composition and installation precautions of directly buried bellows compensator:
Key Features
Strong corrosion resistance: Manufactured with anti-corrosion coating or stainless steel material to ensure long-term stable operation in wet and corrosive environments.
Good sealing performance: Equipped with an efficient sealing system to prevent groundwater infiltration or internal media leakage.
Strong pressure resistance: The influence of external pressure (such as vehicle traffic and building load) is considered in the design, which can withstand certain ground load.
Adapt to multiple displacements: It can handle axial, lateral and angular displacements simultaneously, adapting to complex underground working conditions.
Easy maintenance: Some models support remote monitoring and online overhaul, reducing the cost and time of excavation repair.
Structural composition
Bellows body: Constituted by a plurality of annular corrugations, it is the core component of the compensator and is responsible for absorbing the expansion and contraction deformation of the pipe.
end connector: Typically flanged or welded joints used to connect the compensator to the pipe.
Outer sleeve: Protects the bellows from the outside environment and provides additional mechanical support.
Sealing assembly: Including packing boxes, mechanical seals or other forms of seals to ensure the tightness of the compensator.
Guide device: Make sure the compensator moves only in the axial direction to prevent lateral displacement or torsion.
Anti-corrosion layer: Coated on the exterior surface of the compensator to enhance its resistance to soil corrosion.
Installation Considerations
Select the appropriate burial depth：
According to the local frozen soil thickness, groundwater level and other factors, determine the reasonable burial depth to avoid unnecessary stress on the compensator.
Ensure coaxiality and parallelism：
Keep the compensator aligned with the centerline of the connected pipe during installation to avoid deflection or twisting forces.
Set fixing and guiding brackets：
Install fixed brackets and guide brackets in place to limit the lateral movement of the pipe and guide its movement in the axial direction.
Selection of backfill materials：
Use screened fine sand or crushed stone as backfill material, ensuring uniform compactness and no damage to the compensator.
Waterproofing measures：
For areas with high groundwater levels, effective waterproofing measures should be taken, such as laying impermeable membranes or using waterproof concrete to seal them.
Pre-stretched or compressed (if necessary)：
For some directly buried bellows compensators that need to be "cold tightened", appropriate pre-stretching or compression is carried out according to the design requirements during installation, so as to achieve the best compensation effect at the operating temperature.
Identification and recording：
Mark the position of the compensator before installation, and make detailed records after installation, which is convenient for future inspection and maintenance.
Application Scenario
City heating pipe network: It is widely used in the main pipeline of central heating system to ensure the safety and stability of heat transmission.
Long-distance oil and gas pipeline: For oil and gas transmission pipelines spanning different geological conditions, the directly buried bellows compensator provides a reliable solution.
Industrial water supply and drainage system: In the chemical industry, electric power and other industries, it is used to treat fluid transport pipelines containing corrosive substances.
Municipal Engineering: Directly buried bellows compensators are also commonly seen in underground infrastructure construction such as sewage discharge and rainwater collection.
In conclusion, directly buried bellows compensator has been widely used in many fields by virtue of its unique design and excellent performance. The correct selection and installation of a directly buried bellows compensator not only helps improve the reliability of your underground piping system, but also reduces maintenance costs and extends the service life.