5 Practical components to efficiently design steel beam connections

Sikla is famously known for the welding-free modular framework. A small single-dimensional support or volumetric skid can be built, taken apart and rebuilt using a single type of FLS screw. And yet, various types of progressive welding methods are part of our manufacturing process to deliver the highly engineered product to your projects.
In this article, we will consider the benefits and disadvantages of pre-welded components in the siFramo range from a designer's perspective.

So which components should you consider when designing modular steel frames connections?

In a nutshell, there are two main types of connection – beam to beam connection and beam to primary structure connection. To create those connections, you can use either:

  • Single pre-welded components which come in a form of beam section welded to base plate, e.g. TKO and AK
  • Two separate components which require connecting base plate and beam section using FLS Screws, e.g. STA and WBD.

Steel Beam Connections components

Connecting siFramo steel beam sections

Three components known under abbreviations STA, WD and AK serve the same purpose – connecting siFramo beam sections. Yet, each of them has its advantages when designing frames:

Cantilever Bracket AK Corner Bracket WD
End Support STA F 80end support sta example

Cantilever Bracket AK

cantilever bracket ak example

corner Bracket WDIMG_1148-1
  • Maximum flexibility, as beam section is connected to STA using Self Forming FLS screws
  • Useful for on-site modifications as beam section can be easily replaced
  • Minimal off-cuts
  • Considerably higher loading capacity thanks to beam section and base plate being welded together
  • Less installation time as beam section comes welded to the base plate as standard component
  • A practical medium between STA and AK
  • May provide structural performance benefits in some seismic situations

Connecting siFramo modular frames to primary structures

End connectors WBD and TKO connect siFramo modular frames to primary structures – concrete, primary steel or free-standing, and each has its own benefits:

End Support WBD Beam Bracket TKO

End Support WBD F 80end support wbd example

tko TKO application example
  • Similarly to the STA, maximum flexibility
  • Useful for on-site modifications
  • Minimum off-cuts
  • High load capacity often utilized for large skid frames
  • Saves installation time thanks to beam section and base plate supplied as a single component

Time to balance PROS & CONS: which components to choose?

In summary, requirements vary between flexibility, speed and strength and Sikla developed products to cover all of them. Designers should consider the following pros and cons of AK and TKO compared to their alternatives – STA and WBD:

  • Standard beam section lengths limited to 400, 600, 800 and 1200mm depending on type
  • Shortening the beam section to designed length means short off-cuts with low usability
  • Extending the beam section length requires using a new component
  • Significantly higher loading capacity
  • Halving installation time as the number of connections is reduced from 2 to 1
  • Less self-weight thanks to omitting inserts


We will be more than happy to assist you with your requirements or you can opt-in for our newsletter to stay on top of the thrilling trend of modularisation!

Marek Vargapal

Written by Marek Vargapal

Business Development Engineer (Energy from Waste & Power Generation)