Valve arrangement and diaphragm assembly for a valve arrangement

A valve arrangement comprising a valve housing, a valve inlet, a valve outlet, and a diaphragm assembly for controlling a fluid flow through the valve housing from the valve inlet to the valve outlet, the diaphragm assembly comprising a diaphragm, a diaphragm plate, a nozzle, and a washer being flanged together, the diaphragm plate at least partially covering the diaphragm, the diaphragm being made of non-fiber reinforced PTFE and comprising one or more equalization holes passing through the diaphragm and the diaphragm plate comprising one or more equalization openings passing through the diaphragm plate, the equalization holes being aligned with the equalization openings, wherein the diaphragm plate comprises an engagement zone formed on a surface of the diaphragm plate facing the diaphragm, the engagement zone contacting and at least partially covering the diaphragm, the engagement zone comprising at least one protrusion protruding outward from the surface of the diaphragm plate and engaging a corresponding surface of the diaphragm contacting and at least partially covered by the diaphragm plate, wherein the diaphragm, the diaphragm plate, the nozzle, and the washer are all pressed together via the engagement zone in order to rotationally fix the diaphragm and the diaphragm plate with respect to each other.