No stuffing box, throttling element is elastic diaphragm, ZAZS / ZDLT type electric / electronic diaphragm regulating valve adopts "mountain" convex surface between diaphragm and valve body to seal, body flow channel is smooth, the regulating valve is equipped with multi-spring Film actuators, body liners and diaphragms are made of corrosion-resistant materials with a small output force and are more suitable for demanding corrosion-resistant applications.