Curved tube pressure balanced corrugated expansion joints, also known as curved tube pressure balanced compensators, are installed on pipelines at bends or in spaces connected to equipment. Curved tube pressure balanced corrugated expansion energy-saving compensation for axial and lateral displacement, without generating internal pressure thrust on the pipeline system.
The curved tube pressure balanced expansion joint adopts an elbow structure, on the one hand, to reduce the pressure of the system; On the other hand, in order to prevent high-speed airflow from eroding the balanced expansion joint. This type of expansion joint cannot absorb axial and lateral thermal displacement reactions from the piping system.
The curved tube pressure balanced corrugated expansion joint consists of two working corrugated pipes connected by a working corrugated pipe or an intermediate pipe, a balanced corrugated pipe and structural components such as elbows or tees, head pull rods, end plates, and spherical and conical washers. The expansion joint is mainly used to absorb axial and lateral combined displacement and balance the pressure and thrust of the corrugated pipe.
operational principle
The internal pressure thrust acts simultaneously on the balance expansion joint and the main balance expansion joint of the equipment, with opposite directions. The connecting rod replaces the expansion joint to bear the internal pressure tension. This way, the equipment as a whole is like a "rigid body", and the internal pressure no longer exerts thrust on the fixed support point (support). Due to the same equilibrium diameter of the two sets of expansion joints, they remain in equilibrium regardless of changes in internal pressure.
The axial thermal displacement from the piping system compresses (or stretches) the main corrugated pipe, which is transmitted to the balance expansion joint through a pull rod, causing the balance expansion joint to stretch (or compress). The two thermal displacement reactions have the same direction, and the force borne by the support is the sum of the axial thermal displacement spring reactions of the balance expansion joint and the main expansion joint.
The equivalent axial displacement, bending moment, and shear force of the transverse thermal displacement on the main expansion joint are exactly the same as those on the compound corrugated expansion joint. The pull rod deviates from the original installation state by a certain angle during the lateral thermal displacement of the expansion joint. Due to the use of universal nuts (spherical nuts) at both ends of the pull rod, which act as hinge joints and do not transmit bending moments, the balanced expansion joint is not subject to lateral displacement forces (note: the nut on the other side of the pull rod plate where the universal nut is installed must be locked in the manufacturing factory, and the expansion joint must be loosened after installation on site).
parameter
Product name: Curved tube pressure balanced corrugated expansion joint, nominal diameter: DN300~DN3000 (mm)
Design pressure: 0.1~2.5 (Mpa) Design temperature: -20 ℃~450 ℃
Connection method: flange/welding execution standard: GB/T12777-2008
Materials: SUS304, SUS321, SUS316L, SUS309, SUS310s
Features and uses
The curved tube pressure balanced corrugated expansion joint is mainly used to absorb axial and lateral combined displacement and balance the pressure thrust of the corrugated tube, and is used in situations where large thrust is not allowed. Curved tube pressure balanced corrugated expansion energy saving, vibration absorption and noise reduction, ensuring safe operation of equipment.
This corrugated expansion joint is often installed at the turning point of pipelines (such as L-shaped, Z-shaped pipelines, etc.) or on spatial pipelines connected to equipment, as well as in load sensitive pipeline systems such as pumps, compressors, and steam turbines. It can absorb vibration and reduce dryness, eliminate pipeline thermal stress, and ensure safe operation of equipment.
