MK4 WORLD WIDE, S.L. has been granted DAU 24/148 for its RMSlide spherical and cylindrical bearing.

RMSlide is a spherical and cylindrical bearing which permits rotation and displacement movements by a plane and a curved sliding surface between bearing plates of steel. RMSlide bearings are designed according to EN 1337-7 and may be combined with sliding elements according to EN 1337-2 as shown in EN 1337-1. Instead of PTFE (polytetrafluoroethylene) according to EN 1337-2, MKSM membrane is used for the sliding surfaces of the bearings, which is made of a modified polyamide-polyethylene blend, suitable for low and high temperatures outside the scope of EN 1337-2 with improved load-bearing capacity.

This DAU covers sliding surfaces with a diameter of the circumscribing circle of MKSM sheets greater than 75 mm and lower than 1 500 mm and with long-term temperatures greater than -50 °C and lower than +80 °C. Temperatures above +48 °C are limited to short periods related to weather changes.

The combinations of materials used in the sliding surfaces are given in the table below. Only one combination is used in a sliding surface. The sliding surface is lubricated in accordance with clause 7.4 of EN 1337-2.

RMSlide bearing is intended to be used for the support of bridges or building works in accordance with the scope of EN 1337-1 where the requirements on the individual bearings are critical. RMSlide bearing is suitable for all types of structures, typically made of concrete, steel and composite, as well as for regions with continuously low and high temperatures.

RMSlide bearing is also intended for the use in superstructures where working loads induce fast sliding displacements in bearings.

The provisions made in this DAU are based on an assumed working life of at least 70 years for RMSlide bearing, depending on the accumulated total sliding path assessed, and provided that RMSlide bearing is subject to appropriate use and maintenance. The assumed working life of the RMSlide bearing is of at least 10 years if composite material of type CM1 according to EN 1337-2 is used in guides, instead of MKSM sheets.

The RMSlide bearing is assessed in ETA 23/0869 developed by ITeC and held by MK4. The assessment ETA 23/0869 has been based on the EAD 050078-00-0301 Spherical and cylindrical bearing with special sliding material made of a modified polyamide-polyethylene blend. This DAU includes the assessment carried out in ETA 23/0869, as well as the particular requirements of the Spanish regulations.