Lancashire boiler — identify all applicable classifications How is a Lancashire boiler correctly classified with respect to position, firing, and tube arrangement?

Introduction:
Boiler classification helps engineers understand construction, operation, and typical applications. The Lancashire boiler is a classic shell-type boiler used historically in industries and small power plants. Recognizing its multiple classification attributes ensures correct identification on exams and in practice.

Given Data / Assumptions:

• Conventional Lancashire construction with a large cylindrical shell and two large furnace tubes running longitudinally.
• Fixed installation (not mobile) and typical brickwork settings.

Concept / Approach:
The Lancashire boiler is a horizontal shell, fire-tube boiler: hot gases pass through large furnace tubes within the water-filled shell. It is internally fired because the furnaces are inside the shell. It is stationary in the sense that it is installed permanently on a foundation. Therefore, all of the given correct attributes apply simultaneously.

Step-by-Step Solution:

Verification / Alternative check:
Standard boiler texts depict the Lancashire with two internal furnaces, reversal chambers, and flue passes inside a horizontal cylindrical shell resting on brickwork, confirming all listed classifications.

Why Other Options Are Wrong:

• Selecting only one attribute omits others that are equally true for the Lancashire boiler.
• Water tube, externally fired, vertical: the opposite of Lancashire design attributes.

Common Pitfalls:
Confusing Lancashire with Cornish (single furnace tube); mixing fire-tube with water-tube terminology; overlooking the internal firing feature due to the presence of brick setting outside.

Final Answer: