Abstract: A magnetizer including a housing, a passage arranged inside the housing, and a permanent magnet assembly arranged outside the passage to provide a magnetic field passing through the passage. The housing defines an inlet to the passage and an outlet from the passage such that an object to be magnetised can be inserted into the passage via the inlet in the housing and removed via the outlet in the housing. The passage includes a uniform portion where opposing surfaces of the permanent magnet assembly are arranged a uniform distance apart along the length of the uniform portion and a diverging portion arranged between one end of the uniform portion of the passage and the outlet of the housing.

Abstract: A magnetizer including a housing, a passage arranged inside the housing, and a permanent magnet assembly arranged outside the passage to provide a magnetic field passing through the passage. The housing defines an inlet to the passage and an outlet from the passage such that an object to be magnetised can be inserted into the passage via the inlet in the housing and removed via the outlet in the housing. The passage includes a uniform portion where opposing surfaces of the permanent magnet assembly are arranged a uniform distance apart along the length of the uniform portion and a diverging portion arranged between one end of the uniform portion of the passage and the outlet of the housing.

Abstract: A cylindrical mounting sleeve suitable for mounting a rotor assembly on a shaft, said cylindrical mounting sleeve comprising a hollow cylindrical portion having a length L and an inner surface with a radius R, said cylindrical mounting sleeve further comprising at least one elongated protrusion formed on the inner surface, the elongated protrusion having a height H. The path of the elongated protrusion forms an angle A to the longitudinal centre axis of the hollow cylindrical portion, said angle A being greater than 5 degrees and less than 70 degrees. In this way, a mounting sleeve is provided which reduces the damage during mounting of the sleeve on the shaft. This reduces imbalance in the rotor assembly. The invention also relates to a rotor assembly comprising such a cylindrical mounting sleeve.