Pin member for turbine

A pin member 52 suitable for limiting rotational movement of a shroud relative to a turbine housing. The pin member comprises a generally cylindrical body 53 defining a pin axis 60, and a head portion 54 at one end of the cylindrical body. The head portion is integrally formed with the cylindrical body so that together they form a one-piece unit. The head portion has a limit surface 59 which bears against a surface of the shroud to limit its rotation, and an opposed positioning surface 58 for positioning the pin member. The limit surface and positioning surfaces are spaced from each other in a first direction. The head portion of the pin member has a head surface 55 which is transverse to the pin axis and bounded on opposite sides by the limit surface and the positioning surface. The extent H1 of the limit surface in a second direction transverse to the first direction and to the pin direction is less than the extent H2 of the positioning surface in the second direction.