Mast Standard Section

The mast is the vertical column that gives a tower crane its working height. It is built from identical bolted lattice sections, so the crane is raised one section at a time as the building grows and lowered the same way during dismantling.

Construction

Four square-tube chords form the corners, braced by seamless-tube diagonals welded into a rigid lattice. Every section is interchangeable and joined to the next with high-strength bolts and locating pins, which keeps the mast plumb and the connection repeatable on site. Standard sections are typically supplied in 2.5 m or 3 m lengths.

Role on the crane

The mast carries the full vertical load of the machine and transfers the overturning moment created by the jib, counter-jib and lifted load down to the base frame and foundation. Its stiffness directly affects how precisely the trolley and hook can be positioned at height.

Inspection and maintenance

• Check chord straightness and joint clearances after every climbing cycle.
• Re-torque high-strength bolts to the specified value and replace any that are stretched or corroded.
• Inspect welds for cracks and the paint or galvanised coating for damage; touch up to prevent corrosion.