Arrangement for a method of supporting a side wall of a vertical flue gas pass in a thermal power steam generator

An arrangement for horizontally supporting a first side wall of a top-supported vertical flue gas pass in a thermal power steam generator, wherein the first side wall comprises evaporative water tubes for conveying a mixture of water and steam at a first temperature, and the top-supported vertical flue gas pass comprises a superheating tube for conveying steam at a second temperature higher than the first temperature, the superheating tube comprising multiple rigid, horizontally extending tube legs extending across the top-supported vertical flue gas pass from the proximity of the first side wall to the proximity of a second side wall opposite to the first side wall in the top-supported vertical flue gas pass, wherein the superheating tube is supported from above by a hanger that is, in operation, at a third temperature higher than the first temperature, and the rigidity of the first side wall is increased by each of the rigid, horizontally extending tube legs comprising a first end section and a second end section, each of the first and second end sections being attached to a proximate side wall by an attaching means, wherein the attaching means allows relative movement between a respective end section and the proximate side wall only in a direction slanted from a vertical direction towards the first side wall in downward direction of relative thermal movement between the respective end section and the proximate side wall, but does not allow purely horizontal movement between the respective end section and the proximate side wall.