?隔膜驱动
The PV20CB is a normally closed, diaphragm actuated, spring loaded, direct acting regulator. The pressure set point is adjustable within the spring range. Upstream pressure is sensed under the diaphragm. As upstream pressure increases, the diaphragm pushes against the spring. The pilot stem/ seat is pulled towards the open position, increasing flow through the pilot. As upstream pressure decreases under the diaphragm, the spring pushes the stem/seat towards the closed position restricting flow through the pilot. This sensitive spring/diaphragm interaction closely tacks and responds to changes in upstream pressure.