M24 Rock Bolts (also known as coal bolts) have been developed for use in point anchored or fully encapsulated roof and rib bolting applications.
Manufactured with a rolled M24 x 3.0 mm pitch right hand thread and a ribbed surface profile. Suitable for high load transfer and easy resin and grout application. Supplied complete with an anti-friction washer, dome washer and hexagonal 36 mm drive nut.
Recommended for use in 27 – 28 mm diameter holes. For >28mm diameter holes it is recommended to use Minova Secura bolt range.
Available in either standard “S” mild steel grade or extra high tensile “X” HSAC840 superior steel grade. X steel grade provides greater potential performance in conditions subject to stress corrosion cracking. Multiple lengths, diameters, pin and paddle configurations are available.
We can supply a comprehensive range of plates for use with Coal bolts. Plates most typically used with Coal bolts are:
LOKSET® RESIN CAPSULES
The Lokset resin system provides rapid anchoring of the bolt to the surrounding strata. The rotation of the bolt during installation ruptures the capsule, shreds the skin and mixes the two components transforming the resin mastic into a solid anchor.
Standard “point” anchorage will be firmly interlocked with the substrate and bolt within minutes. The setting time of the resin components can be controlled. A combination of fast and slow setting cartridges makes it possible to simultaneously anchor, grout and tension the rock bolt.
|MECHANICAL PROPERTIES||M24 X GRADE||M24 S GRADE|
|Nominal Rib Height Diameter (mm)||23.2||23.2|
|Nominal CrossSectional Area of the Bar (mm2||370||370|
|Yield Stress (Strength MPa)||650||340|
|Yield Force Diameter (MT)||24.6||12.8|
|Tensile Stress (Strength MPa)||890||490|
|Tensile Force Typical (MT)||33.7||18.6|
|Elongation (%) 5D||19||27|
|Mass per metre – Bar (kg/m)||2.9||2.9|