A separator assembly for removing material that is entrained in a gas stream. The separator assembly comprises a housing having a head part which provides the upper end of the housing and a body part which provides the lower end of the housing. The separator assembly also comprises a shield which extends across the housing towards the lower end thereof so as to leave a collection space between it and the lower end in which material that is separated from the gas stream can collect. There is at least one opening in or around the shield through which the material can flow past the shield into the collection space. The separator assembly further comprises a liner sleeve which covers at least a part of the inside wall of the body part between the shield and the upper end of the body part.