Open Section Type M

M-type (or Sigma type) open section profiles are made of galvanized metal sheets and can be used as structural profiles in all types of steel constructions. Their main use is to support the wall or roof structural elements of the building, such as cladding panels, in all types of buildings.

They are distinguished for:

  • Excellent bearing capacity as a structural component
  • Excellent reaction to fire, category A1
  • Excellent weather and corrosion resistance
  • Acceptance of intumescent paints where required
  • Easy and fast standard mounting

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SKU: 1016 Category:

Open section type M175, M205, M235, M265 profiles

M-type cold rolled open section light profiles are manufactured on the basis of the company’s high quality criteria covering a wide range of applications. Produced in desirable lengths up to 14m depending on project requirements. It is possible to be produced with punched holes of diameter Φ6, Φ8, Φ10, Φ12.5, Φ14, Φ16, Φ18, Φ20, Φ22 at any point with excellent precision.

Open section Type M profiles, due to their design, carry the largest loads than the other open section (type C and type Z) and can even be used as columns and beams in light constructions.

Open section type M profiles, are usually used as girts or purlins to support the wall cover or roof cover of the building. Obviously the number of applications of these metal profiles is unlimited, provided that the static study of the structure has been issued.

  • Width 175mm, 205mm, 235mm and 265mm
  • Nominal sheet thickness 1,50mm, 2,00mm, 2,50mm, 3,00mm
  • Fixed lengths up to 14m, depending on the project requirements
  • Optional punched holes Φ6, Φ8, Φ10, Φ12.5, Φ14, Φ16, Φ18, Φ20, Φ22,      in any position

Metal Sheets

Open section type M profiles are mainly manufactured of high quality and durable galvanized steel sheets that are produced according to EN 10346 and EN 10143, regarding quality and tolerances standards. The thickness of the metal sheets ranges from 1,50mm up to 3,00mm.

Galvanized steel sheets, without color coating
  • high quality metal sheets from DX51D to S350GD,
  • hot dip zinc protection Ζ 70 ~ 275 gr/m2
  • aluzinc protection AΖ 70 ~ 265 gr/m2

Open Section Type M profile

M 175 M 205 M 235 M 265
Nominal sheet thickness [mm] Weight per unit length [kg/m]*
1,50 3,90 4,30 4,60 5,00
2,00 5,20 5,70 6,10 6,60
2,50 6,50 7,10 7,70 8,30
3,00 7,80 8,50 9,20 9,90

* Weight per unit length was calculated taking into account the specific weight of steel = 7850 kg/m3.

Open section type M profiles are fixed to the structure by the standard screw connecting method. It is not recommended the application of self-drilling screws or rivets. In general, welding is not recommended for this type of profiles.

Open section type M profiles cannot be overlapped. J connectors/sleeves (open section type J profiles) are used to join the parts together. The thickness of the steel sheets of the connectors is always equal or greater than the thickness of the section profiles, and their length depends on the span between the supports. It is recommended to place the joints always at the support positions (columns, rafters).

For structural construction, strength reduction of the profile due to the holes, should be calculated taking into account the provisions of EN 1993-1-3.