Patent ID: 8915483

Claim:
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, wherein the sidewall in the passage is in direct contact with the valve stem at the second section with the second cross sectional area, the valve stem has a nominal outer cross sectional area or an outer diameter that is larger than the second cross sectional area or a diameter of the passage at the second section, and the valve stem comprises an outer, flexible material such that, when the valve stem moves past the second section, the second section causes the valve stem to flex in a direction that is transverse a direction of movement of the valve stem.