Technical Specifications

  • steel property class 8 according to DIN EN 20898-2
  • operational temperature from -10 to +250 °C
      Note: At high temperatures, a reduction of preload will occur
  • tension at core cross section 90% RP 0.2
  • maximum values include all reaction loads, such as operational load, impact fractors, as well as changes in pretension due to thermal load



MJP mechanical Multi-Jackbolt-Pretensioners P8 have been designed according to DIN EN and correspond to steel property class 8 for nuts on bolts 8.8 (according to DIN EN specified up to M39). All sizes have been designed according to the same guidelines.

MJP Mechanical Multi-Jackbolt-Pretensioners P8 are being used for general bolting in all areas of industry. The hexalobular head (Torx®) of the jackbolts is extremely wear-resistant and very practical in its ease of handling.


Fields of Application

General mechanical engineering, shipbuilding, heavy mechanical engineering, power plants, chemical industry. Used on couplings, slewing bearings, foundations, presses, bolted split joints and many more.



  • tools, such as impact sockets (Torx® sockets), torque wrenches, pneumatic impact wrenches
  • stud-bolts
  • lubricants
  • corrosion protection
  • accessories (caps, covers, plates, ...)
  • various thread profiles
  • large dimensions
  • all materials
  • technical examinations and audits

Patent pending ®

 pdfDatasheet MJP P8.pdf281.14 kB