Abstract: A pressure relief valve for pressure equalization between an essentially closed space and the surrounding atmosphere is disclosed. The pressure relief valve includes a valve housing with:—a wall defining a flow passage with an upwardly oriented outflow,—a valve body arranged to cooperate with a valve seat arranged in the outflow,—a stem configured for axial guidance of the valve body,—a damper arranged to dampen axial movement of the stem, wherein the damper is configured such that force curves of compression and expansion respectively diverge due to hysteresis loss or pronounced hysteresis loss.

Abstract: A pressure relief valve for pressure equalization between an essentially closed space and the surrounding atmosphere is disclosed. The pressure relief valve includes a valve housing with: a cylindrical wall defining a flow passage, a valve body arranged to cooperate with a valve seat arranged in the outflow of the valve housing, a stem configured for axial guidance of the valve body, a lifting element or plate arranged further down in the flow passage relative to the valve seat, a flow constriction defining an essentially truncated conically shaped interior and arranged to encircle the lifting element such that a radial passage between the lifting element and flow constriction increase when the lifting element and the valve body is moved from a closed state of the pressure relief valve towards an open state of the pressure relief valve.

Abstract: A pressure relief valve for pressure equalization between an essentially closed space and the surrounding atmosphere is disclosed. The pressure relief valve includes a valve housing with: —a wall defining a flow passage with an upwardly oriented outflow, —a valve body arranged to cooperate with a valve seat arranged in the outflow, —a stem configured for axial guidance of the valve body, —a damper arranged to dampen axial movement of the stem, wherein the damper is configured such that force curves of compression and expansion respectively diverge due to hysteresis loss or pronounced hysteresis loss.

Abstract: A pressure relief valve for pressure equalization between an essentially closed space and the surrounding atmosphere is disclosed. The pressure relief valve includes a valve housing with: a cylindrical wall defining a flow passage, a valve body arranged to cooperate with a valve seat arranged in the outflow of the valve housing, a stem configured for axial guidance of the valve body, a lifting element or plate arranged further down in the flow passage relative to the valve seat, a flow constriction defining an essentially truncated conically shaped interior and arranged to encircle the lifting element such that a radial passage between the lifting element and flow constriction increase when the lifting element and the valve body is moved from a closed state of the pressure relief valve towards an open state of the pressure relief valve.