Boiler structure and method of assembly

Abstract

A support structure for a boiler envelope, for example being the boiler envelope of a boiler thermal plant, a boiler structure so supported, and a method of supporting a boiler, are described. The support structure includes a support platform structure, comprising a part of the primary load bearing boiler cold structure for the boiler envelope, and adapted to engage with and thereby carry at least a major part of the static load of the boiler envelope. The support platform structure is provided surroundingly about the boiler envelope at a support platform level substantially below full envelope height and provided with associated further boiler cold structure in such manner that at least the substantial majority of the boiler cold structure is at or below the support platform level and preferably such that essentially all the boiler cold structure is at or below the support platform level and only elements of the boiler hot structure and the boiler pressure parts extend above the support platform level supported by the boiler cold structure.

1 . A support structure for a boiler envelope, for example being the boiler envelope of a boiler thermal plant, comprising:
 a support platform structure, comprising a part of the primary load bearing boiler cold structure for the boiler envelope, and adapted to engage with and thereby carry at least a major part of the static load of the boiler envelope;   wherein the support platform structure is provided surroundingly about the boiler envelope at a support platform level substantially below full envelope height and provided with associated further boiler cold structure in such manner that at least the substantial majority of the boiler cold structure is at or below the support platform level.   
     
     
         2 . A support structure in accordance with  claim 1  comprising:
 a boiler support cold structure including a support platform structure and a boiler support hot structure supported via the boiler support cold structure; 
 wherein the support platform structure is provided surroundingly about the boiler envelope at a support platform level substantially below full envelope height and configured such that at least the substantial majority of the boiler cold structure is at or below the support platform level. 
 
     
     
         3 . A support structure in accordance with  claim 1  wherein essentially all the boiler cold structure is at or below the support platform level and only elements of the boiler hot structure and the boiler pressure parts extend above the support platform level supported by the boiler cold structure. 
     
     
         4 . A support structure in accordance with  claim 1  wherein the support platform structure comprises a substantially horizontal framework of structural members extending around and supporting the boiler envelope at a height substantially below the boiler maximum height. 
     
     
         5 . A support structure in accordance with  claim 1  further comprising suitable secondary and tertiary structural elements, including suitable cross members, beams, ties, buckstays, tensile members and the like. 
     
     
         6 . A support structure in accordance with  claim 1  wherein the support platform structure is provided in association with a boiler at a height above the burners of the boiler but below the heating surfaces of the boiler. 
     
     
         7 . A support structure in accordance with  claim 1  wherein the support platform structure is provided in association with a boiler such that all the boiler cold structure sits at or below a maximum height level which maximum height level is above the burners of the boiler but below the heating surfaces of the boiler. 
     
     
         8 . A support structure in accordance with  claim 1  wherein the support platform structure is provided in association with a boiler at a height of around 40 to 60 per cent of a boiler envelope maximum height. 
     
     
         9 . A support structure in accordance with  claim 1  wherein the support platform structure is provided in association with a boiler such that all the boiler cold structure sits at or below a maximum height level which maximum height level is around 40 to 60 per cent of a boiler envelope maximum height. 
     
     
         10 . A boiler apparatus comprising a support structure in accordance with  claim 1  in conjunction with and providing at least a major part of the static load support for a boiler envelope of a boiler. 
     
     
         11 . A boiler apparatus in accordance with  claim 10  wherein the boiler is a utility boiler for thermal power generation. 
     
     
         12 . A thermal power generation plant including at least one boiler apparatus in accordance with  claim 10 . 
     
     
         13 . A method of assembly of a boiler structure comprising the steps of:
 providing a support structure for a boiler envelope in accordance with the above described first aspect of the invention;   assembling a boiler envelope so as to be mechanically supported thereon in such a manner that at least the major part and preferably substantially all of the boiler cold structure is at or below the support platform level.   
     
     
         14 . The method of  claim 13  wherein the boiler envelope is supported such that there is essentially no boiler cold structure above the support platform level and essentially only elements of the boiler hot structure and the boiler pressure parts extend above the support platform level. 
     
     
         15 . The method of  claim 13  wherein the steps of providing a support structure, and assembling in a supporting manner thereon a boiler envelope structure, are performed progressively in parallel.