A pipe cleaning device has a housing movable along a pipe to remove a coating. Temporal and locality caching hints and prefetching hints are provided to improve system wide caching and prefetching. The phase change material is non-encapsulated or in raw form and the first material includes a viscosity modifier selected from polyolefines having a density in the range of 890-970 kgm3 as measured at room temperature according to ISO 1183-2 and a melt flow rate in the range 0.