Product Main

Specifications

Expansion Joint for High Voltage Apparatus
Structure Diagram
 
 

Technical Data Sheet
 
Design Pressure: ≤0.75Mpa
Design Temperature: -35℃~150℃
Axial Movement: -20mm~20mm
Lateral Movement: -10mm~10mm
Medium: Sulfur Hexafluoride Gas or other gas of arc extinction and insulation. 
Cycle Life:Above 10000 times

Performance & Characteristic 
As a connect unit between the covers of two adjacent equipment , Expansion Jointfor High Voltage Apparatus mainly used for adjusting the installation, compensate the relative displacement and the movement caused by Expansion and Contraction. General expansion joints always used under the condition of High Stress (Namely, large movement), but this expansion joint always used under the condition of Low Stress (Namely, small movement). 
As the holder of the composite apparatus can’t bear much pressure, so the structure should be designed to Pressure Balance Type so that the expansion jointscan balance the force produced by inside pressure rely on the elastic force of the disc spring to reduce the pressure on the holder. The composite apparatus are full of expensive media of SF6 gas, annual air leakage ≤1%,or it will lower the reliability of the products when it operating, if seriously, it will lead to the power cut and the overhaul of the whole system, so the require to the gas tightness is pretty high. 
This expansion jointused as an electric elements, require the inner surface is very smooth and no cusp, or there maybe electric discharge, influence the insulating property of the products.  

Variety and the Form of Structure
 
Variety
 
Form of Structure
Device of Pressure Balance
Installation Compensator
Bellowswelded onto the flange
            —
Bellows welded onto the Tube Ends and the Tubes Ends welded onto the flange.
            —
Temperature Compensator
Bellows welded onto the flange
Disc Spring/No device of Pressure Balance
Bellows welded onto the Tube Ends and the Tubes Ends welded onto the flange.
Disc Spring/No device of Pressure Balance
Bellowswelded onto the Fanstone Flange
Disc Spring/No device of Pressure Balance
Pressure Balance Bellows
Self Balance of this structure


                                                   Test Methods before delivery
 
Test of Performance
Welding Joint
Physical Dimension
Tolerance of the dimension
Axial Spring Rate
Test of Compensation Rate
Pressure Test
Pressure Stress Test
Test of the stabilization
Test of the Air Tightness
Test of Cycle Life
Test of bursting pressure
Air Tightness Test to the
Sulfur Hexafluoride Gas
 
Expansion Joints for High Voltage Apparatus