EXPANSION SHELL BOLTS

• KR-1/Ø28-M18, KR-2/Ø28-M18

Intended use

• KR-1/Ø28-M18 and KR-2/Ø28-M18 expansion bolts are designed for use in roof and ribs control as an independent or secondary roof bolting system. They can also be used for suspending various elements of mining equipment.

Technical description

• KR-1/Ø28-M18 and KR-2/Ø28-M18 expansion shell bolts can be made from the following rod types:

Bolt rods are plain steel bars of ø18,3 mm made of AP 600 steel in accordance with ZN-97/AP-2 standard

The rods may vary in terms of shape and the size of swelling at the bottom. The top of the rod ends with a rolled M18 thread.

• KR-1/Ø28-M18 and KR-2/Ø28-M18 expansion shells measuring 28 mm in diameter set the bolt in the hole.
  KR-1/Ø28-M18 shell consists of a serrated sleeve of ø28 and one plug, KR-2/Ø28-M18 shell consists of two serrated sleeves and two plugs.
• Bolts may be fitted with the following types of washers: square, square with a side hole, round or octagonal.
  The washer plates vary in terms of press forming method and thickness. The washers have a center hole of ø27 mm or ø29 mm. Plates with side hole of ø15 can be used for attaching elements of mining equipment and should be used when there is no hole in the rod.
  All the washers are made of 6 mm plate.

Technical data

Installation procedure

• Bolts should be installed in a dry drill hole made with a ø28 mm bit, after cleaning the drill dust.
  The hole length should be the same as the bolt.
  Assemble the bolt by putting a washer and screwing the shell on the rod.
  Insert the bolt into the hole and push until the washer rests against the rock surface.
  Rotate the bolt causing the expansion of the shell in the hole.
  Tighten the bolt applying 250 Nm torque in order to obtain the prestress of at least 30 kN.