The present invention relates to a vacuum pump (62) having a rotor device (64) and the stator device (66). The stator device comprises a first portion made of corrosion-resistant material (68), the first portion, in use to pump fluid from the inlet of the stator device (72) to the outlet (74), the rotor defining volume that is swept by the device (70). The second portion of the stator device (76) is made of a thermally conductive material, the second portion, the interface surface between the heat generated within the first portion first portion and a second portion surrounding the first portion so that it can be transmitted to the second part (78). The second part (76) in, to be able to transfer heat from the second portion to the liquid coolant carrying liquid coolant through the second portion to cool the stator device at least one duct (80) is formed.