BABCOCK & WILCOX SUPERHEATERS 



FORGED -STEEL ROUND SUPER- 

 HEATER HANDHOLE FITTINGS 



AS APPLIED TO STIRLING BOILERS 



IN Stirling boilers the superheaters are placed directly behind the front bank 

 of tubes below the middle drum. This location, relative to the pressure 

 parts of the boiler, which is clearly indicated by the illustration, is covered 



by patents. 



Owing to the method of introducing 



steam into the superheater when installed 



in this design of boiler, the cored type is 



ordinarily furnished. 



CONSTRUCTION The superheater 



headers are of extra heavy wrought -iron 



pipe of sufficient diameter to give the 



desired velo- 

 city of steam 



through this portion of the apparatus. The pipe is 

 flattened top and bottom, as shown in the sectional 

 view for that portion of its length inside the boiler 

 walls or for the portion into which tubes are 

 expanded, and handholes are provided. 



The tubes are 2-inch, cold drawn, seamless 

 steel, bent to a "U " shape, expanded at the ends 

 into bored seats in the upper flattened portion of 

 the superheater headers. By a variation in the 

 length and spacing of the tubes, the requisite 

 amount of superheating surface is provided to 

 give the desired degree of superheat. 



Opposite each tube end in the lower flattened 

 portion of the superheater header there is pro- 

 vided an individual circular handhole, which gives 

 access to the end of the tube for expanding and 

 for inspection. These handholes are machine faced 

 back from the edge a sufficient distance to make 

 a seat and are closed by circular, inside fitting, 

 forged-steel handhole plates shouldered to center 

 in the opening, the flanged seats being milled to a 

 true plane. A ^-inch bolt, forged integral with 

 the handhole plate, extends through the opening 

 and a wrought-steel crosspiece extending across the 

 opening on the outside holds the plate in place. 

 The bolt extending through this crosspiece receives 



CROSS SECTION SUPER- 

 HEATER HEADER SHOW- 

 ING HANDHOLE FITTINGS 

 ASSEMBLED AND METHOD 

 OF HOLDING CORE 

 IN PLACE 



57 



