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Accreditations Northern Precision Ltd operate a quality management system in accordance with ISO 9001. The ISO 9001 standard is recognised worldwide and you can be assured of the benefits of working with a certified company knowing that our management systems are constantly assessed and improved.
Registered in England & Wales Company number 3275391
V.A.T Registration number GB 684 1384 17
Specialist Fasteners for Sheet Metal
+44 (0) 1302 836010
+44 (0) 1302 831555
Self-Clinching Fasteners Broaching Fasteners Arnold & Shinjo Fasteners Rivet Bushes Rivet Nuts Weld Fasteners Spring Steel Fasteners Blind Rivets Inserts for Plastics Inserts for Stone, Solid  Materials, Composites & Sandwich Panels Crown-Nuts Fast-Con Installation Equipment Turned & Cold Formed special parts made to order Bespoke fastener design & development Fastener & Application testing Technical support ISO 9001 RoHS|WEEE Compliance REACH Compliance Conflict minerals Environmental Policy  OUR PRODUCT RANGE  SERVICES & SUPPORT  INSERTS FOR STONE,  SOLID MATERIALS, COMPOSITES & SANDWICH PANELS Keep-Nut Guide Keep-Nut Flush Keep-Nut Flanged Keep-Nut Stud Master-Plate Guide Master-Plate Stud Master-Plate Blind Standoff Master-Plate Through Standoff Master-Plate Through Nut Deform-Nut Guide Deform-Nut Type TC Keep-Nut hole preparation Keep-Nut hole gauging Keep-Nut insertion Keep-Nut installed
Prepare hole in base material to correct specification.
Verify hole diameter using Go/No-Go gauge.  Check hole depth against reference line on Go side of gauge.
To ensure correct installation it is recommended that a  threaded mandrel is used. Fully screw on the insert and drive into the hole.
Unscrew the mandrel and the insert is installed and ready for use.
Keep-Nut with bracket
Example assembly
Granite 20mm
Marble 20mm
Travertine 20mm
Fibre cement (high density) 12mm
Fibre cement (high density) 10mm
Fibre cement (high density) 8mm
HPL 12mm
HPL 10mm
HPL 8mm
Corian 12mm
Corian 10mm
Agglomerate stone 15mm
Tempered glass 5mm
Keep-Nut Type
KN4 M6 H8.5
KN4 M6 H8.5
KN4 M6 H8.5
KN4 M6 H8.5
KN4 M6 H8.5
KN2 M6 H6
KN4 M6 H8.5
KN4 M6 H8.5
KN2 M6 H6
KN4 M6 H8.5
KN2 M6 H6
KN4 M6 H8.5
KN1 M4 H5
Average pull-out load on a single insert (Kg)*
Comparison of results from tests carried out on a range of materials.
* Tests were carried out under laboratory conditions. Pull-out figures are indicative only and are offered for guidance purposes. It is recommended that you undertake your own tests in the actual application panel material.
With Keep-Nut, radial force is produced only while the insert is under tensile load. With Keep-Nut, the crowns spread the loads into the parent material, allowing large loads to be carried. With Keep-Nut, the thread stops before end of the insert, avoiding extraction as a result of the use of an excessively long bolt. Keep-Nut can carry very high structural loads without the need for resins or adhesives.
Advantages Simple hole preparation Quick installation No need for resins or adhesives Radial force is produced only while the insert is under tensile load. The crowns spread the load into the parent material, allowing large loads to be carried Thread stops before end of insert, avoiding extraction as a result of the use of an excessively long bolt
Keep-Nut® is a press-in threaded insert that utilises a mechanical anchoring feature, to provide permanent threads in panels made of marble, granite or other stones, as well as composites, carbon, Corian®, HPL, glass and others solid surface materials. Keep-Nut is manufactured in stainless steel and consists of a threaded bush, a set of toothed spring washers (crowns), and a plastic ring holding the parts together. Available in different lengths, with or without flange, to fit several different panel thicknesses, Keep-Nut can be installed quickly since the user simply needs to drill the material with the correct hole diameter and press-in the insert. Keep- Nut can also be customised with different versions and sizes, to meet specific customer requirements. The Keep-Nut insert is specifically developed to fasten ventilated façades, wall-coverings, décor and interiors, furniture, kitchen and sanitary elements, as well as a variety of other applications. Keep-Nut inserts have several advantages compared to other fasteners for stone and solid materials. The preparation needed is just a cylindrical hole – an undercut hole is not required – which means that standard tools can be used. In addition, assembly by pressure is quick and easy and does not require use of any additional resins or adhesives. Keep-Nut inserts can be used for hidden assemblies without any protruding parts, facilitating the handling and installation of a variety of materials. In use, the crowns are engaged by axial force, acting radially against the hole wall, effectively permanently locking the insert in place. In addition, the internal thread does not run completely through the bush, which prevents extraction as a result of the use of an excessively long screw. Keep-Nut is a trademark of SPECIALINSERT S.r.l., Corian is a trademark of E. I. du Pont de Nemours and Company.
KEEP-NUT is a press-in threaded insert for stones such as marble and granite as well as composites, carbon, Corian, HPL, glass and others solid surface materials. Keep-Nut applications Northern Precision Ltd YouTube Channel FLUSH FLANGED STUD