MF39 Friction Bolts(Split set bolt)

MF39 Friction Bolts also called Split Set Stabilizer,Friction Bolts Split Sets, is an indispensable advanced material for underground mining support.

MF39 Friction Bolts  is a very specific support product, and it is an advanced material used for the support of the roof of the underground copper or gold mining and other projects.

Product Description


MF39 Friction Bolts are rock bolts with only 2 parts, a tube and matching domed bearing plate. The high strength steel tube is slotted along its length. One end is tapered for easy insertion into a drill hole and the other has a welded ring flange to hold the bearing plate.

With the bearing plate in place, the tube is driven into a slightly smaller hole, using the same standard percussion drill that made the hole.       

As the tube of the rock bolt slides into place, the full length of the slot narrows, causing radial pressure to be exerted against the rock over its full contact length.

MF39 Split Set Bolt is mainly used to establish ground support when hand-held mining operations are required. Our MF47 Split Set Bolt was made by high strength steel strip which special refined with very low level of Si & P in chemical components, it will make the bolt in perfect performance of supporting rocks, and help to have a good quality in galvanizing. Meanwhile, with our advanced PLC-controled auto welder, the bolt will has a very good performance when it is inserted in the rocks.

DimensionsPhysical PropertiesTechnical Data
Bolt DiameterA39mmYield StrengthMin. 345 Mpa (85KN)Recommended Normal Bit Size35-38mm
Bolt LengthB0.6-2.4mTypical 445Mpa(110KN)
Taper End DiameterC30mmTube Ultimate Tensile StrengthMin. 470 Mpa (115KN)Typical Breaking Capacity124KN
Taper Slot WideD2mmTypical 530Mpa(130KN)
Taper LengthE65mmMass per Meter1.92 KgsMin. Breaking Capacity89KN
Bolt Slot WideF17mm
Ring LocationG3mmCross Section Area245 mm²Recommended Initial Anchorage3-6 Tons (27-53 KN)
Material GuageH2/2.5mm
Ring Wire GuageI6mmHole Diameter Range35-38mmUltimate Axial StrainTypical 21% (Thk<16mm)
Ring Open GapJ5-6mm


MF39 Friction Bolts can be load tested by fitting a special ring to the bolt prior to its installation.  Pull tests can then be conducted with a hollow ram hydraulic jack.Further corrosion protection can be provided by hot dip galvanizing.

The same as the self-drilling anchor bolt the surface treatment methods can be hot-dip galvanized, electro-galvanized or surface epoxy coating, and all need to be used with Volcano Plate.

Bolt DescriptionDiameterLengthSurface FinishWeightPacking
Friction Bolts MF39-60039600Untreated1.2200
Friction Bolts MF39-90039900Untreated1.7200
Friction Bolts MF39-1200391200Untreated2.4200
Friction Boltst MF39-1800391800Untreated3.2200
Friction Bolts MF39-2400392400Untreated4.35200
Friction Bolts MF39-600 HDG39600Hot Dip Galvanized1.26200
Friction Bolts MF39-900 HDG39900Hot Dip Galvanized1.83200
Friction Bolts MF39-1200 HDG391200Hot Dip Galvanized2.56200
Friction Bolts MF39-1800 HDG391800Hot Dip Galvanized3.39200
Friction Bolts MF39-2400 HDG392400Hot Dip Galvanized4.56200


The JIUFU Underground Mine Friction Bolts is manufactured from high strength steel tube which has a slot along its entire length.   A ring, or collar, is welded on the outer end to hold a domed plate to the rock surface.

MF39 Friction Bolts(Split set bolt)


Friction Bolts Product Features

1.The raw material is made of high-strength alloy steel strip.

2.The installation is the simple.

3.No anchoring agent is required.

4.The friction strength between the bolt and the rock is large.

5.It has high shear and tensile strength.

6.Equipped with a high-strength plate.