Difference Between Cornish and Lancashire Boilers

For better understanding, the difference between Cornish and Lancashire boilers is tabulated first. Next, each difference will be discussed in the following section, with additional details among other differentiating features between the two boilers.

A comparative view of the two fire-type steam boilers, Cornish and Lancashire, is presented in the table below.

Sr. #Boiler Differentiating AspectCornish BoilerLancashire Boiler
1Shell Diameter1.25 – 2 m2–4 m
2Shell Length5–8 m8–10 m
3From the front end to that of the back via. two flue tubes and then back to the front via. one bottom flue and finally to the back end again via. two side flues
10–14 bar15–20 bar
4Steam Generation Capacity2000 –4000 kg/hr.8000 –10,000 kg/hr.
5Number of Internal Flue Tubes12
6Number of Side Flues22
7Number of Bottom Flues11
8Path of Flue Gases in BoilerFrom the front end to that of the back via. two flue tubes and then back to the front via.  one bottom flue and finally to the back end again via. two side flues
From the front end to that of the back via. two flue tubes and then back to the front via.  one bottom flue and finally to the back end again via. two side flues
9Initial CapitalLesserHigher
10PopularityNoYes

The above comparison gives some interesting observations, which are summarised below for concise understanding:

  1. Lancashire boiler is bigger than Cornish Boiler: The diameter as well as length of the former is larger than the latter. It implies that the Lancashire boiler requires a larger footprint (more space) compared with the Cornish boiler.
  2. The final pressure of the steam in Lancashire is of much better quality as its pressure is higher and, therefore, it is capable of giving more output per kg of steam than its Cornish counterpart.
  3. The steam generation or evaporative capacity of the Lancashire boiler is way above two times that of the Cornish boiler.
  4. The number of internal flues is two in the Lancashire boiler compared with the Cornish boiler, which has only one.
  5. Although the number of side flues and bottom flues is the same in both the boilers, their sequence opposes each other.
  6. The path adopted by the flue gases in the boiler flues is such that in the Cornish boiler, burned gases first pass through two side flues and then one bottom flue, whereas in the Lancashire boiler, they first enter one bottom flue and then divide into two side flues.
  7. The initial capital and running cost of the Lancashire Boiler are higher than those of the Cornish boiler.
  8. Cornish boilers are less popular than Lancashire boilers.
  9. The brick-setting, which is required for boiler insulation and structural integrity, is quite complex in the case of the Lancashire boiler on account of its double flue design compared with the Cornish boiler due to its simple single-flue design.
  10. The thermal efficiency of the Lancashire boiler is higher than that of the Cornish boiler.
  11. Due to its smaller size and compactness, the Cornish boiler is easily portable compared with the Lancashire boiler, which, on account of its heavy and sturdier design, is difficult to relocate.
  12.  The safety protocols of both boilers are almost the same; however, Lancashire boilers require more attention to occupational safety and hazards and risk management than in the case of the Cornish boiler category.
  13. The cornish boiler is typically used in small scale industries in comparison to the Lancashire boilers, which are used in relatively big scale industries due to their higher steaming capacity.
  14. The breakdown, as well as repair maintenance of the Lancashire boiler, is a bit challenging on account of its dual flue design compared with its single flue Cornish counterpart.
  15. Cornish boilers are mostly not recommended for use where the demand for steam is variable with time or at unsteady demand. Lancashire boiler is a fit choice where changing steam demands are to be met.