Abstract: Actuator for a seat valve or a butterfly valve which is of the type that is normally closed (NC) or normally open (NO), and also has a cylinder and a piston being held in the normal position by a spring. The spring includes a closed space with a pressurized fluid, and the actuator further has at least a top unit, with two or more connections for a pressurized fluid. The actuator is with one of the connections in the top unit that is connected to the inside of the cylinder through one or more openings at one end of the cylinder and another connection is connected to the inside of the cylinder through one or more openings at the other end of the cylinder. The top unit is designed to allow the connections to be interchanged by changing the position of the top unit, e.g. by turning the top unit 180 degrees around an axis corresponding to or parallel to the axis of the piston and cylinder.

Abstract: A valve comprising a valve housing with a valve bonnet, an inlet opening and an outlet opening, the valve bonnet having a passage for a valve stem, the passage having a sidewall and the valve stem comprising a valve disk for closing the valve by bringing the valve disk in contact with a valve seat in the valve housing, the passage in the valve bonnet comprising at least a first section with a first cross sectional area and a second section with a second cross sectional area that is smaller than the first cross sectional area. The sidewall in the passage is in direct contact with the valve stem at the second section with the second cross sectional area.

Abstract: A valve comprising a valve housing with a valve bonnet, an inlet opening and an outlet opening, the valve bonnet having a passage for a valve stem, the passage having a sidewall and the valve stem comprising a valve disk for closing the valve by bringing the valve disk in contact with a valve seat in the valve housing, the passage in the valve bonnet comprising at least a first section with a first cross sectional area and a second section with a second cross sectional area that is smaller than the first cross sectional area. The sidewall in the passage is in direct contact with the valve stem at the second section with the second cross sectional area.

Abstract: Actuator (1) for a seat valve or a butterfly valve which is of the type that is normally closed (NC) or normally open (NO), and also contains a cylinder (3) and a piston being held in the normal position by a spring. The spring virtually consists of a closed space with a pressurised fluid, and the actuator further consists of at least a top unit (7), with two or more connections (12, 13) for a pressurised fluid. The actuator is with one of the connections in the top unit that further is connected to the inside of the cylinder through one or more openings at one end of the cylinder and another connection is connected to the inside of the cylinder through one or more openings at the other end of the cylinder. The top unit is with a design allowing the connections to be interchanged by changing the position of the top unit, e.g. by turning the top unit 180 degrees around an axis corresponding to or parallel to the axis of the piston and cylinder.