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HomeMy WebLinkAboutInformationR!'tWVLPLUG Page 1 of 3 ES IC r t ., Home About Us Products Technical Divisions Information Direction of Loading The direction of the applied load must be considered to determine the most appropriate anchor. The tension and shear components must be less than the recommended Toad/design resistance in the direction concerned. Tensile Loads Tensile loads are applied along the axis of the fixing (see fig. 1). Common examples include suspended ceiling applications and the suspension of mechanical services, pipework and ductwork etc. Shear Loads Shear Toads act at right angles to the axis of a fixing and directly against the face of the structural material (see fig. 2). Shear performance is governed mainly by the shear strength of the bolt material and compressive strength of the supporting substrate. Oblique/Combined Loads Oblique Toads are a combination of tension and shear components (see fig.3). If the angle of applied oblique load is within 10o of pure tension or pure shear, the safe working load for that direction may be assumed. Otherwise, the applied oblique load should be resolved into its shear and tensile components. Offset Loads Offset loads act at right angles to the fixing axis but are offset from the surface (see fig. 4). In this situation, the d bolt, due to bending, needs to be considered as well as the shear capacity of the anchor. Careers Con Slotted Holes in Fixture When fixing anchors through slotted holes it is important to ensure that there is adequate surface contact betw and the fixture to guarantee a positive clamping force. If in doubt a square plate washer with a thickness of 3mm o be recommended in place of the standard washer supplied. Diamond Drilled Holes When holes are formed in a structure using a diamond drilling system extra care is required to ensure tha thoroughly cleaned by brushing and blowing at least three times. Also to create a key for the anchor, (particula anchor is installed) the sides of the hole should be roughened up by inserting a standard masonry bit into hole hammer action drilling machine. A resin with minimal shrinkage such at Rawl R-KEX should be selected for diamond drilled holes. http://www.rawlplug.co.uk/index.php?option=com_content&task=view&id=36&Itemid=0 4/9/2008 RAWLPLUG Page 2 of 3 Installation Anchor choice may be affected by certain aspects of the ins for instance the desirability of a through fixing. The fixture can used as a template, and the fixing made through nominal c holes without the need for the object to be removed and replac Key Points To achieve published performance values, it is that all anchors are installed correctly in accordance with Raw installation instructions. Some basic points to remember are: ■ Drill correct diameter hole, to the correct depth. ■ Clean the hole thoroughly. This is important for all anchors, but critical for bonded anchors. ■ Use the correct setting equipment and procedure. ✓ Tighten to the recommended torque. Recommended Tightening Torques In torque controlled expansion anchors a clamping force is exerted through the fixture into the base material. The is directly proportional to the tightening torque. Tightening the anchor enables the expander to key into the surrou providing a secure fixing (see fig. 5). Tightening to Rawl Fixings' recommended tightening torques ensures that the clamping force is greater than the working Toads. These torques should not be exceeded as this may overstress the bolt and/or base material. Ad wrenches of the 'break back' type are recommended for setting fixings. Expanding Fixings Torque controlled anchors transmit expansion forces by locally compressing the substrate. The forces are exerte expansion, not over the whole length of the fixing. On applying the load to the anchor, additional forces are exert the light blue area ie. concrete cone (see fig.6). It is this projected area which relates to the performance of the anchor. Therefore as embedment depth is increase cone and the greater the performance of the anchor (see fig.7). Any reduction in the projected area, for example are placed too close together or too near the edge of the concrete (see fig.8 and fig. 9) will result in reduced p http://www.rawlplug.co.uk/index.php?option=com_content&task=view&id=36&Itemid=0 4/9/2008 RAWLPLUG Page 3 of 3 should be avoided if possible. Where unavoidable, the appropriate reduction factors shown for reduced spacing or edge distance should be recommended load/design resistance indicated for the anchor. :: New job opportun ies available!!! :: Visit us on International Hardware Fair/ Practical ©Copyright 2007 Koelner S.A. All r http://www.rawlplug.co.uk/index.php?option=com_content&task=view&id=36&Itemid=0 4/9/2008