DEMOUNTABLE DERRICK
Demountable derrick type stacks are one type of support system for an elevated flare. The
elevated flare tip is mounted on top of a riser supported by a steel trussed (derrick)
structure. Similar to a conventional derrick supported flare system, demountable derricks
require three or four additional foundations for the derrick legs. Due to the economic impact of
shutting a flare down and the requirement for large cranes, users welcome a means to be able to
lower the flare tip to grade for maintenance, inspection, or repair activities without ever
having to shut the flare down. A demountable derrick allows a user the ability to lower the
flare tip and pilots to grade through the use of a winch system (typically three different
winches), guide rails, tilting tables, and flanged riser sections. Demountable derricks
eliminate concerns associated with process temperature designs. Additionally, a single common
demountable derrick structure can support multiple flare risers.