Single type (hinge) expansion joint

    A single type (hinge) expansion joint is composed of a connecting pipe, a corrugated pipe, and a pair of hinges connected to the connecting pipe. It has the ability to withstand internal pressure thrust and is used to absorb angular displacement of a single plane.

    Pressure level: 0.1MPa-2.5MPa.

    Connection method: 

        1. flange connection type

        2. connecting pipe connection typeAngular compensation of stainless steel expansion joint products: ± 4 degrees - ± 9 degrees

        Material selection:

    Single type (hinge) expansion joints are mostly made of Aoshi stainless steel sheets, and the thickness of corrugated pipes for pipelines is generally between 0.4-3mm. The forming process is the process of plastic deformation of the substrate, which causes the material of the mechanism to undergo loading and unloading within the plastic range, resulting in significant changes in the performance of the structural material, which is known as hardening phenomenon. Generally, after the corrugated pipe is formed, the yield strength of the material will increase significantly. During use, it was found that stress corrosion caused a significant amount of damage to the compensator. To overcome these two types of corrosion, commonly used methods are to perform solid melting treatment on the formed corrugated compensator and select a new type of high nickel corrugated pipe material.

    The main causes of corrugated failure in single type (hinge) expansion joints are fatigue failure, corrosion failure, and torsion failure:

    1. Poor water quality treatment, Cl ions in steam, causing stainless steel ripple pitting or lattice corrosion;

    2. Transport medium high-pressure steam, linear speed υ> At speeds above 30m/s, turbulence is formed at tees, elbows, and valves, causing damage to the original design guide tube of the ripple compensator due to low-frequency and significant vibration. Especially for large diameters and large compensation guide tubes with L>460mm, fatigue fracture and blowing off of the guide tube are more likely to occur;

    3. Design or operational errors, resulting in steam water impact, explosive water hammer, and severe damage to ripple compensator components;

    4. The large diameter spiral pipeline, due to its internal stress not being eliminated, causes distortion and damage to the corrugated joint due to restoring stress;

    5. One of the reasons for the torsional deformation and damage of corrugated components is the installation deviation, sliding of the fixed pier, and loss of stress balance.

    Application scope of hinged corrugated pipe expansion joint:

    Mainly used in complex piping systems, compensating for angular displacement of piping systems, such as L-shaped pipes, Z-shaped pipes, U-shaped pipes, etc