A pump for delivering a fluid includes: a pump housing having an inlet and an outlet, and having an inner circumferential face; a drive shaft; an eccentric inside the pump housing, the eccentric being eccentrically movable relative to the pump housing; a deformable element arranged in a pump gap between the inner circumferential face and an outer surface of the eccentric, the deformable element and the inner circumferential face defining a delivery channel. The deformable element is forced against the pump housing by the outer surface of the eccentric along at least a portion of the delivery channel such to form a sliding sealing of the delivery channel that can be slid along the delivery channel from the inlet to the outlet to deliver fluid by movement of the eccentric. A reinforcing ring has a coefficient of thermal expansion smaller than a coefficient of thermal expansion of the pump housing.