Patent ID: 11686185

Abstract:
High pressure gas lift valve with dual edge welded bellow subassembly where two bellows are incorporated in sealed configuration filled with silicone oil. Bellows are of different sizes featuring equal volumetric oil displacement for the pre-set total compression/expansion which corresponds to equal stem travel. By design both bellows can be fully compressed solid preventing bellows overstressing allowing extremely high pressure to be applied to both bellows. Lower bellow effective area is larger for orifice area than upper bellow area. This eliminates differential pressure across the bellows during valve opening resulting in equalized internal/external bellow stresses. Both bellows work only in compression from free length to full compression.This results in bellow internal/external pressure and stress level equalization and long cycle life. Valve withstands high injection pressure for well integrity testing. Once lower bellow is fully compressed solid high pressure would not be transmitted to upper bellow and vice versa.