SPECIAL ROOF ARCHES

• V25 beam section
• V29 beam section

Intended use

• ARNALL special roof arch made of V25 section is used to reinforce roof and ribs of rectangular roadway workings.
• The concept of special roof support is a result of our cooperation with mining industry and caters for the mines’ demand for rectangular steel arch which allow wide workings and optimum cutting area.

The arch is mostly used in cross-cuts support and while cutting a drift in independent roof bolting system with continuous mechanical miners when crossing zones with deteriorated geologic and mining conditions.

Technical description

• Special roof support arch consists of overlapping V25 section elements connected by means of SD25 or SDO25 shackle.
• The type of arch in Figure 1 is used for the reinforcement of rectangular roadway workings in the following sizes:
  • - height: from 2200 mm to 4000 mm
  • - width: from 3200 mm to 7500 mm

The arch consists of 5 or 6 elements depending on its width.
The roof part of the arch is made of one or two straight elements (roof bar) while the side part comprises two elements of different curving (roof arch and side arch), turning into straight sections at overlap, which makes joining possible despite various radius.
All the arches have overlaps of 500 mm in length.
The height of the frame can be changed by changing the length of the side arch and its curvature radius.
The width can be changed by using one or two straight elements forming the roof beam.

• The type of arch in Figure 2 is used for the reinforcement of rectangular roadway workings in the following sizes:
  • - height: from 2200 mm to 4000 mm
  • - width: from 3200 mm to 7500 mm

The roof part of the arch is made of two roof beams having straight sections in the roof area and the overlap area, while the side part of the arch is made of side beam having straight sections in the side area and the overlap area.

In all the arches the overlap between the side beam and roof beam is min. 500mm while between two roof beams the overlap is from 600 mm to 1,500 mm.

The height of the arch can be changed by changing the length of the straight section of the side beam.

The width can be changed by changing the length of the straight section of the roof beam or by a bigger overlap.

• In order to increase the load capacity, the arch should be bolted with one or two sets of bolts.
• ARNALL special roof support system was used in the following mines: "Jankowice", "Chwałowice", "Staszic", "Ziemowit", "Silesia" and "Budryk".

Intended use

• ARNALL special roof support arch made of V29 section is used to reinforce roof and ribs of rectangular roadway workings.
• The concept of special roof support is a result of our cooperation with mining industry and caters for the mines’ demand for rectangular steel arches which allow wide workings and optimum cutting area.
  The arch is mostly used in cross-cuts support and while cutting a drift in independent roof bolting system with continuous mechanical miners when crossing zones with deteriorated geologic and mining conditions.

Technical description

• Special roof support arch consists of overlapping V29 section elements connected by means of SD29 or SDO29 clamps.
• This type of arch is used for the reinforcement of rectangular roadway workings in the following sizes:
  • - height: from 2200 mm to 4000 mm
  • - width: from 3200 mm to 7500 mm

• In order to increase the load capacity, the arch should be bolted with one or two sets of bolts.
• ARNALL special roof support system was used in the following mines: “Rydułtowy-Anna”, "Jankowice" and "Chwałowice".