There are great differences between the friction coefficients for the common material combinations. That is why it is important that you always know some key data. If in doubt, take the lower value. This is also applicable when estimating the location of friction joints, namely the connecting points between materials.
Example: A pallet is on the bed of the trailer, movement between bed and pallet can occur, but also between the pallet and goods and between the individual parts of the load. The respective weakest point is taken for the evaluation.
The table opposite shows the dynamic friction coefficients. It is also assumed that the load always moves a little during the journey, as a result of vibration, so that the initial adhesion is irrelevant.
If in doubt, take the smallest coefficient of friction, e.g. μ = 0.2 for a loading surface with no grouting.