Which tool is commonly used for ensuring alignment in boiler components?

The spirit level or laser level is commonly used in the alignment of boiler components because it helps ensure that surfaces are level and aligned correctly during the installation or adjustment process. When working with large and heavy boiler components, it's crucial to achieve precise alignment to prevent structural issues and ensure the safe and efficient operation of the equipment.

A spirit level provides a simple visual indication of whether a surface is level, while a laser level projects a line that can be used to check alignment over longer distances or in larger areas. These tools are particularly effective in identifying any discrepancies in height or alignment that may occur when various components are installed within a boiler system.

While other tools such as a straight edge are also useful for checking flatness and alignment, they do not provide the same level of precision or ease of use over larger areas as a laser level can. Calipers and micrometers are more suited for measuring dimensions and tolerances rather than ensuring alignment of large components.