Abstract: An axial flow steam turbine has a self-locking nozzle block wherein the nozzle block has radially inwardly and outwardly extending flanges that seat in grooves formed in spaced shrouds of the nozzle ring, with locking pins provided, in bores in a rear arcuate section of the nozzle ring, formed from the material that has a thermal coefficient of expansion greater than the thermal coefficient of expansion of the material from which the nozzle ring is formed. Preferably, the nozzle block is formed from a material having a thermal coefficient of expansion comparable to that of the pins. Steam passing through the turbine heats its assembly such that the locking pins force the flanges of the nozzle block into sealing contact with a first arcuate section of the nozzle ring so as to prevent vibration and loosening of the nozzle block in the nozzle ring.

Abstract: A nozzle chamber assembly comprising an upper nozzle chamber resting on a lower nozzle chamber wherein the nozzle chambers are neither bolted nor pinned at their horizontal juncture but are held together by gravitational and pressure forces. A removable bolt which passes through the upper portion of the inner cylinder during assembly of the turbine and threads into the upper portion of the nozzle chamber to fasten the upper nozzle chamber in the upper portion of the inner cylinder during assembly and is removable once the inner cylinder is assembled. The inlet nozzles for the turbine and nozzle chambers are slidably received and sealed in a common bore which extends through the inner cylinder.