Pipe spreaders type RMR V29 RMR-V29 spreader tubes are used to stabilize and connect V29 roof support arches.

Technical description

Pipe spreader 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: ø 42.4 x 2.9 mm or 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 V29 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 spreader to the V29 arches.

The spacer’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


Techncal data


V29 Spacer tube diameter

ø42,4 x 3,2 mm

Arch spacing

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

U bar or hook bolt thread

M20 mm

RMR-V29 spreaders comply with PN-G-15000-7:1996 standard: “Supporting roadways with channel section arches”.


Assembly of RMR-V29 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-V29 arch tube spreader has a Certificate allowing the product to be marked with the safety mark No. B/1294/IV/2014 issued by Central Mining Institute in Katowice.