Mast (technology)
The mast (v. Althochdt .: mast ) is a vertically standing pillar like , non-walk-through human structure . It can be constructed from a wide variety of materials. Its footprint is small compared to its height.
purpose
A mast is usually used to attach:
- Sailing (sail mast), the loading boom or the like, for example on ships . See: ship mast
- Flags ( flagpole )
- Antennas or as a self-radiating transmission mast , antenna mast or radio mast
- Airships - see: anchor mast
- Lighting , for street lighting , traffic lights or floodlights
- Advertising, signs and directional signs, e.g. B. as an overhead signpost on roads
- Power lines, see: Overhead line mast
- Ropes (suspension ropes, pull ropes, conveyor ropes, etc.), e.g. B. in aerial cableways as a cable car support for supporting or tensioning suspension ropes and hoisting ropes
construction
Masts can differ considerably in terms of their dimensions and construction. So there are telephone poles often from a simple round wood - pile , high masts on the other hand consist of complex tower-like structures, eg. B. steel trusses or pipe-like constructions that are similar in construction to factory chimneys . The dimensions range from manageable posts only a few meters high, on which signs are attached, to elaborate structures that are among the tallest human structures overall.
Other subdivisions
- general: telephone mast , overhead line mast
- by function: Abspannmast , supporting mast , overhead line mast , Transposition Tower , mast separator , branch pylon , finishing period , distribution transformer
- according to the material from which the mast is made: wooden mast , concrete mast , tubular steel mast , lattice mast
- according to construction method: portal mast , one- level arrangement , Danube mast , Christmas tree mast , barrel mast
Differences between mast and tower
Frequently, masts are separated from towers by referring to free-standing structures as towers, and those tied with ropes as masts . However, this distinction is not always made in practice, because according to this definition, overhead line masts, since they are almost always designed as free-standing structures in Central Europe, would not be masts. There are also constructions that represent a mixture of free-standing tower and guyed mast ( hybrid tower ). The pre-standard DIN V 4131: 2008-09 “Antenna structures made of steel” defined in section 3.3 the tower with a free-standing, cantilever-bearing structure and the mast with a structure that is held by cables anchored to the ground or another structure at different heights . This prestandard was withdrawn in June 2011.
Broken mast
The mast can break due to mechanical overload or immediate destruction in the event of a collision. Material fatigue , corrosion or (in the case of wooden poles) weakening as a result of inadequate wood protection can be the cause or favor . The forces acting include wind pressure on the mast or attached parts, depending, for example, on the sail area on a ship's mast and the wind strength. In addition, gravitational forces act. Inertial forces arise on vehicles in particular , which result from their movements as a result of swell or terrain . Vibrations of the mast as a result of the forces acting on it can encourage mast breakage or cause a resonance catastrophe . Snow load or ice load (also with overhead lines and ropes) can also lead to overload.
Plural
There are two plural forms for mast , for which no meaning difference is given in the spelling dictionary; the "mast" form is rarer according to Duden. - The superset of masts can be differentiated into subsets of masts according to function, material and type of construction . There are only masts on a ship as the ship has already been selected from a collective of ships. Shipyards, on the other hand, specialize in ship masts. The distinction is now often ignored.
- Masts - distributive plural emphasizing diversity (unlimited whole made of identical parts)
- Masts - a collective plural that emphasizes the whole (a limited whole made up of identical parts) emphasizes the same type of function, material or construction.
