Innovative Stainless Steel Applications in transport ... - Euro Inox

Another typical way to join a hollow section to a structure or to machinery is by using
lugs. The most common function of a lug is to transfer loading from a machine (usually
a hydraulic cylinder) or a mounting to a structural hollow section. The shape and
location of the lug affect the strength of both the joint and the structural hollow section.
For example, in Figure 46, if force F is placed to act at a distance of e = b from the
centre of the profile the load does not cause distortion of the cross-section.
Figure 46. Principle and application of lugs (Yrjölä 2008).
If a load will not cause torque in the chord, the load can be transferred using a lug of the
same height as the chord. Using a lug of equal height decreases deformation in the
chord-member’s side wall (Figure 46 centre). If a load will cause torque in the chord, it
is recommended to design a lug that will prevent cross-section deformation caused by
loading, (Figure 46 right).
Hydroformed connectors
An innovative way to avoid one of the most critical issues in hollow-section
constructions (locating welds outside high-stress and stress-concentration areas) is to
use pre-fabricated connector pieces. Using such pieces moves the welded joints away
from the most critical areas: the joint corners. This is of particular importance in
fatigue-loaded applications, such as transport vehicle structures.
61