Vertical boiler


A vertical boiler is a type of fire-tube or water-tube boiler where the boiler barrel is oriented vertically instead of the more common horizontal orientation. Vertical boilers were used for a variety of steam-powered vehicles and other mobile machines, including early steam locomotives.

Design considerations

Tube arrangements

Many different tube arrangements have been used. Examples include:
;Fire tubes
;Water tubes
The main advantages of a vertical boiler are:
The main disadvantages of a vertical boiler are:

Railway locomotives

Several manufacturers produced a significant number of vertical boiler locomotives. Notable amongst these were:
The Sentinel Waggon Works also produced a range of road lorries based on their high-pressure vertical boilers

Steam tractors

The Best Manufacturing Company of San Leandro in California produced a range of steam tractors that used vertical boilers.

Steam rollers

Certain designs of steam roller departed from the conventional traction engine style of a horizontal boiler with an engine mounted above. Vertical-boilered rollers were built around a substantial girder frame chassis, with the boiler being mounted low down between the front and rear rolls. Such designs were not common in the UK.

Steam donkeys

The traditional form of steam donkey married a vertical boiler with a steam engine on a rigid base fitted with skids for mobility. Since the ground to be traversed would be rough and rarely level, the water-level -tolerant design of the vertical boiler was an obvious choice.

Steam shovels and cranes

Construction equipment such as steam cranes and steam shovels used vertical boilers to good effect. On a rotating base, the weight of the boiler would help to counterbalance the load suspended from the shovel bucket or crane jib, mounted on the opposite side of the pivot from the boiler. The compact boiler footprint permitted smaller designs than would have been the case for a horizontal type, thus allowing use on smaller worksites; the extra height of a vertical boiler being less critical for such a generally tall machine.

Marine applications

Some steam boats, particularly smaller types such as river launches, were designed around a vertical boiler. The small footprint of the boiler permitting smaller, more space-efficient designs, with less of the usable vessel being occupied by the means of propulsion rather than the payload.

Stationary applications

Vertical types such as the Cochran boiler provided useful, small footprint, package solutions for many stationary applications, including process and space heating.