Arch tube spreaders Type RMR V25 are used to stabilize and connect V25 roof support arches.

Technical description

Frame spreader tubes consist of the following elements:
- connecting tube (connector)
- holder
- U bar or hook bolts

The connector, which is the main spacing element, is manufactured in the following sizes ø42.4 x 3.2 mm. Its length depends on the arch spacing. Both connector ends are appropriately beveled and formed into oval shape to achieve better adherence to the holder. Assembly holes of ø22 mm make it possible to join the connector with V25 section.

The holder is made of a flat bar of 8 x 40. The middle part of the holder tightly adheres to the arch section and the arms fit the connector.

U bar and hook bolts are made of plain bar with M20 thread.

Holders, U bars, hook bolts, nuts and washers are elements used for fastening spacers to the V25 arches.

The spreader’s design ensures appropriate fixture. You only need to pay attention to tightening the bolts.

Spreaders are easier to assemble than the ones used so far.

The spreader is ideal in sloping excavation areas.

Tests with spreaders prove that they exceed the requirements concerning axial strength resistance.

Technical data


V25 Spacer tube diameter

ø42,4 x 2,9 mm ; ø42,4 x 3,2 mm

Arch spacing

500 ; 750 ; 1000 ; 1200 ; 1250 ; 1500 mm

U bar or hook bolt thread

M20 mm

RMR-V25 spreaders comply with PN-G-15000-7:1996 standard: “Supporting roadways with channel section arches”.



Assembly of RMR-V25 arch spreader begins with putting on first M20 hook bolts or M20 U bar and then holder. At the end of the assembly connecting tube should be fixed with M20 nuts. It is important to tighten the nuts fastening the spreader to the arch, inspect the structure regularly and tighten the connections as well as the arch locks. The number of spreaders depends on the size of the support arch.
The spreader should be at least 0.3 m away from the beam ends.

RMR-V25 arch tube spreader has a Certificate allowing the product to be marked with the safety mark No. B/1295/IV/2014 issued by Central Mining Institute in Katowice.