The diaphragm is fastened to the shaft sleeve with a pin and generally does not loosen or cause backlash between the diaphragm and the shaft sleeve.Some manufacturers provide two diaphragms, and some provide three diaphragms, with one or two rigid elements in the middle, and the two sides are connected to the shaft sleeve.The difference between the single diaphragm coupling and the double diaphragm coupling is the ability to handle various deviations. In view of the complex bending of the diaphragm, the single diaphragm coupling is not suitable for eccentricity.The double diaphragm coupling can bend in different directions at the same time to compensate for eccentricity.