The self-operated low-pressure regulating valve employs a balanced single-seat design, offering stable pressure, high accuracy, and excellent sealing performance for controlling minute differential pressures. The set point can be adjusted freely during operation. It is widely applicable for non-corrosive gas media with outlet pressure (mm water column*) ranging from 0.14 to 7.2 kPa, operating at pressures not exceeding 1.4 MPa and temperatures not exceeding 120°C (or 150°C). It is extensively used in nitrogen sealing systems for various oil products, chemicals, and liquid storage tanks.