Nozzle module, nozzle diaphragm, steam turbine, method for assembling nozzle diaphragm, method for assembling steam turbine, and method for disassembling steam turbine

A nozzle ring to be disposed between an inner ring extending in a circumferential direction around a central axis and an outer ring disposed outward of the inner ring in a radial direction from the central axis and extending in the circumferential direction, the nozzle ring comprising:

• an upper half nozzle ring disposed upward in a vertical direction with reference to the central axis and has a semi-annular shape formed around the central axis, and
• a lower half nozzle ring disposed downward has a semi-annular shape formed around the central axis, wherein
• the upper half nozzle ring and the lower half nozzle ring each comprise a plurality of nozzle modules,
• each of the plurality of nozzle modules comprises:
• a nozzle body having a blade shape in a cross section and extending in the radial direction;
• and
• a platform member integrally connected to an end portion of the nozzle body in the radial direction,
• the platform member comprises:
• a first portion formed on a first side in an axial direction in which the central axis extends at the platform member and having a pair of first side surfaces extending in the axial direction when viewed in the radial direction;
• and
• a second portion formed to extend to a second side in the axial direction with respect to the first portion at the platform member and having a second side surface extending obliquely with respect to the pair of first side surfaces when viewed in the radial direction,
• the plurality of nozzle modules includes:
• first nozzle modules;
• a second nozzle module;
• a third nozzle module;
• and
• a fourth nozzle module,
• the first nozzle modules, the second nozzle module, the third nozzle module, and the fourth nozzle module each have a different configuration of the platform member,
• the second nozzle module and the third nozzle module are disposed in an end portion on a first side in the circumferential direction in the upper half nozzle ring and the lower half nozzle ring,
• the fourth nozzle module is disposed in an end portion on a second side in the circumferential direction in the upper half nozzle ring and the lower half nozzle ring, and
• the first nozzle modules are disposed between the fourth nozzle module, and the second nozzle module and the third nozzle module in the circumferential direction in the upper half nozzle ring and the lower half nozzle ring.