SK128993A3 - Steam generator - Google Patents

Abstract

In the case of a suspended steam generator employing the system of natural circulation or forced (fan-assisted) circulation, in particular a waste heat boiler downstream of gas turbines, the steam collecting drum 6 is mounted on brackets 4 over the downcomers 1, with the result that the mounting point is arranged in the vicinity of the inlet collecting chamber (header) 2 of the evaporator heating surface 3, and the weight of the steam collecting drum is introduced via the bracket 4 into the housing 5 of the suspended steam generator. <IMAGE>

Description

Technical field

The invention relates to a steam generator. which is suspended or constructed behind a natural or forced circulation system, in particular a waste heat boiler downstream of a steam-powered thermal power plant machine, which is arranged above substantially horizontal tubes of the evaporator heating surface and which is connected to the evaporator heating surface by downpipes and risers .

BACKGROUND OF THE INVENTION

Steam generators are known in which both the housing and the steam drum are suspended or mounted in a single support system. The disadvantage of this construction is that, in the operation of the steam boiler, a thermal extension is created between the steam drum, where the collecting chambers are provided, which are necessary to substantially equalize the elastically extensible construction of the connecting pipe.

DE-B 1 929 286 discloses longitudinally variable pivot supports for compensating the expansion between the wall of the combustion chamber and the surrounding supporting device.

From AT-PS 310 776, steam generators of standing construction are also known, in which the steam drum is supported by means of downcomers on a common basis with the combustion chamber. This construction is limited by the strut length of the downcomers and leads to downcomer systems of downcomers whose downcomers are connected by a spatial structure, as is apparent, for example, from AT-PS 378 250.

SUMMARY OF THE INVENTION

It is an object of the invention to counter different thermal expansions and to take advantage of the physical effect that the downcomers and flow tubes between the drum and the evaporator as well as the connecting pipes between the steam drum and the superheater have roughly the same temperature, virtually boiling point. Indeed, by supporting the steam drum on the casing at approximately the height of the evaporator heating chambers, preferably via the downcomers, most of the different expansion of the drum connecting pipes to the collecting chambers is captured by varying the height of the steam drum and independently of the boiler support.

The invention is based on the fact that the connecting tubes, in particular the downcomers, are arranged roughly at the height of the collecting chambers, in particular the inlet collecting chamber and the evaporator heating surfaces on the brackets of the suspended or erected steam generator housing and support the steam drum.

Overview of the figures in the drawing

The invention is explained in more detail below by way of example with reference to the drawing.

In FIG. is a schematic representation of a steam generator according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

The waste heat steam generator is arranged downstream of the gas turbine 10, for example, in which the turbine flue gas is cooled to superheated steam. The steam produced is utilized by the condensation steam turbine 11 for power generation.

The waste heat steam generator is formed with a horizontally arranged heating surface 3 of the evaporator, arranged downstream of the system with natural or forced circulation.

The steam bracket 4, the drum 6, which is a steam generator, so that it rests with its arranged weight of the steam downcomer and the housing 5 of the hanging drum 6 is introduced via a suspension device 12 into a steel support device 13 or via a support into the foundation. The downcomers 7 are guided on the housing 5 to prevent the relative oscillations between the sliding guide 7 so that even with the downcomer 7 ^{and the} wall 5 of the housing 5 are guided on the housing 5. Likewise, the steam drum 6 is swiveled by the holder 7; oscillations between the casing 5 and the steam drum 6. The casing 5 for waste heat boilers is generally formed by an insulated sheet metal wall, and can also be formed as a tubular wall with longitudinal ribs i.

The downcomers 1 are connected at their support to the inlet chamber 2 of the evaporator heating surface 3 by means of arcuate fittings 8, which arcuate fittings 8 can be made very short. The wet steam formed is led by means of risers 9 to the steam drum 6, where it is separated from the entrained water and then fed as saturated steam to the superheater heating surfaces 14 which are surrounded by hot flue gas in front of the evaporator heating surfaces 3 and disposed below the heating surfaces. 3 evaporator. The heating surface 3 of the evaporator is preferably formed by ribbed tubes, in particular tubes with reinforcing ribs. The inlet manifolds 2 can also be mounted on the bracket 4 to prevent different expansion.

In the context of the invention, the steam generator can also be arranged to stand on the ground, wherein the downcomers 7 which carry the steam drum 6 are supported on the wall of the steam generator by means of brackets 4 in the region of the inlet manifolds 2 of the horizontally arranged heating surfaces 3 of the evaporator. The steam pipes flowing through the steam can also be used to support the steam drum.

Claims (8)

PAT E N T 0 V É 1. Steam generator, which is suspended or built on carrier construction i for system natural or forced circulation especially a boiler on the waste heat behind the machine tepe 1 nej a steam drum power plant which is arranged above the substantially horizontal tubes of the evaporator heating surface and which is connected to the evaporator heating surface by means of connecting tubes, for example by downpipes and risers, characterized in that the connecting tubes, in particular downpipes ( 1) are arranged roughly at the height of the collecting chambers, in particular the inlet collecting chamber (2) and the evaporator heating surface (3) on the brackets (4) of the hinged or mounted steam generator housing (5) and support the steam drum (6). Steam generator according to claim 1, characterized in that the downcomers (1) and optionally the steam drum (6) are mounted on the housing (5) extensively by means of a guide (7), in particular pivotable holders (7), Steam generator according to claim 1, characterized in that the downcomers (1) are connected to the inlet header (2) by means of an arcuate fitting (8). Steam generator according to Claim 1, characterized in that the housing (5) is provided with longitudinal ribs. according to claim 1, characterized in that it is formed by a tubular wall s Steam generator according to claim 1, characterized in that the wall of the housing (5) is formed by an insulated sheet metal. Steam generator according to claim 1, characterized in that the evaporator heating surfaces (3) are formed by fin pipes, in particular reinforcing fin pipes, which form a horizontally arranged tube bundle and connected by non-heated downcomers (1) and risers (9). ) with a steam drum. Steam generator according to claim 1, characterized in that the inlet header (2) and the downcomers (1) are mounted on a common console (4). Steam generator according to claim 1, characterized in that the heating surfaces (3) of the evaporator are arranged above the heating surfaces (14) of the superheater in terms of height. List of used reference pipes 1 inlet manifold 2 evaporator heating surface 3 console 4 cabinet 5 steam drum 7 swiveling grip 7 arc fitting 8 riser 9 gas turbine 10 condensation steam turbine 11 suspension 12 steel support 13 heating surface superheaters 14