Stam boiler

 Vertical-Tube Boiler

In some fire-tube boilers, the tubes run vertically, as 

opposed to the horizontal arrangement in the 

Scotch boiler. The vertical-tube boiler sits in an

upright position . Therefore, the 

products of combustion (gases) make a single pass, 

traveling straight up through the tubes and out the 

stack. The vertical fire-tube boiler is similar to the 

horizontal fire-tube boiler in that it is a portable, self-

contained unit requiring a minimum of floor space. 

Handholes are also provided for cleaning and 

repairing. Though self-supporting in its setting (no 

brickwork or foundation being necessary), it MUST 

be level. The vertical fire-tube boiler has the same 

disadvantages as that of the horizontal-tube 

design—limited capacity and furnace volume.

Before selecting a vertical fire-tube boiler, you must 

know how much overhead space is in the building 

where it will be used. Since this boiler sits in an 

upright position, a room with a high ceiling is 

necessary for its installation.

The blowdown pipe of the vertical fire-tube boiler is 

attached to the lowest part of the water leg, and the 

feedwater inlet opens through the top of the shell. 

The boiler fusible plug is installed either (1) in the 

bottom tube sheet or crown sheet or (2) on the 

outside row of tubes, one third of the height of the 

tube from the bottom.