Mungo Dictionary of Fastening Technology: Anchor Terms Explained

Key things to remember

The essentials from this document in plain words. Check the full document before you rely on a figure.

• ✓Setting data symbols: hef is effective anchorage depth, h0 drilling depth, hmin minimum thickness of the concrete member and tfix usable length.
• ✓For groups of fixings, spacing of 3 times the setting depth must be used to achieve maximum loads. Minimum edge distances also apply, to avoid failure of the building material.
• ✓Recommended loads are found under laboratory conditions and do not allow for edge or centre distances; they are not always equal to approved loads. Working loads for products with a European Technical Approval include a partial safety factor.
• ✓Force is given in kN or N: 1kN = 1,000N, roughly 100kg.
• ✓Drilling: rotary for timber, board, plasterboard, aerated concrete and perforated brick; percussion for solid block brickwork; hammer drilling with SDS bits for concrete and natural stone.
• ✓Anchor types covered: torque controlled expansion, hammer set, nylon plug, cavity wall, chemical and concrete screw. Minimum setting depths must not be cut short; plaster, flagstones and insulation do not count towards setting depth.
• ✓Zinc coated anchors are for indoor fixings except wet rooms (zinc coating 5 microns). Outdoors, in wet rooms, humid industrial air and near the sea, stainless A4 (1.4401 or 1.4571) is required.

Who it helps: Builders, engineers and staff who want the anchor terms on Mungo data sheets explained.