Close this search box.


The Gund Company is the sole distribution channel for Ranprex® in North America.

Ranprex ® is a highly densified laminated wood insulation utilized for electromechanical applications and is extensively used in the liquid filled power and distribution transformer industry. Most important, the material complies with the norms DIN7707 and IEC61061.

Typical insulation components include:

  • Clamping or Pressure Rings
  • Core Blocks
  • Step Blocks
  • Cooling Plates
  • Lead and Cleat Structures
  • Pressure Beams
  • Fasteners (Threaded Rod & Nuts)
  • Round Spacers
  • Coil Supports
  • Shield Ring

The Gund Company manufactures a wide range of insulation materials for the various types of transformers that are available today. Our application engineering expertise can help you understand both your insulation material selection and your component configuration options – whether it’s for large liquid filled transformers, dry type distribution transformers or low-voltage electronic transformers.

Rancan is produced in Italy, particularly by pressing red beech veneers that incorporate a patented thermosetting resin at a predetermined temperature. The result is a dense and exceptionally strong material that is ultimately suitable for many different applications.

Ranprex ® offers excellent electrical and thermal insulation properties. In addition to that, it also provides outstanding physical and mechanical properties in terms of its ability to compress, bend and successfully handle strong impact. This laminated densified wood insulation is self-lubricating and highly wear-resistant. There is even remarkable resistance to high and low temperatures, as well.

In the long run, the high-quality products and close work with the most significant transformer OEMs in the world enabled Rancan to become the largest producer of densified laminate wood for liquid-filled transformer applications. Rancan is essentially a leader in the production of Laminated Densified Wood, which is typically used in all industrial sectors. As a result, the company has been able to successfully reach top rated standards of quality.

The Gund Company recommends Ranprex ® for its various characteristics. These characteristics are mainly given by the special exploitation of its fibres. Thus, making this material different and distinct from all other composites.

The important characteristics of Ranprex®:

  • Withstands heavy workloads and impacts, while preventing delamination
  • A notably low specific weight
  • Minimal friction and wear
  • Remarkable self-lubricating capability
  • Outstanding resistance to both high and low temperatures
  • Exemplary electrical insulating properties
  • Excellent thermal insulation characteristics
  • Low thermal conductivity
  • Remarkable dimensional stability

Ranprex® offers the following advantages:

  • Excellent dielectric properties
  • High oil absorption
  • High mechanical properties
  • Suitability to work at high temperatures
  • High dimensional stability
  • Wide range of density selections, according to your needs
  • Lower cost than other materials that are used for similar applications
  • Negligible shrinkage
  • Low humidity level

Ranprex ® material is available in the following grades:

Parallel Construction:
P1R / KP20210 / ML22EL
P2R / KP20212 / ML20EL
P4R / KP20214 / ML15EL

Crosswise Construction:
C1R / KP20220 / ML22E
C2R / KP20222 / ML20E
C4R / KP20224 / ML15E

Tangential Construction:
T2R / KP20242 / ML20ET
T4R / KP20244 / ML15ET

Fore more information, see our Material Data Sheets.

Over the past 70 years, The Gund Company has grown into one of the largest manufacturers and fabricators of composite materials, thermoplastic materials and elastomeric materials. We have multiple locations across North America with state-of-the-art machining capabilities – such as CNC panel saws, mills and routers. Not only does The Gund Company have stocking locations across the USA, Mexico and Canada, but we can also guarantee the delivery of raw sheets or finished components with the shortest possible lead time. Our application engineering focus continues to strengthen, as we take our materials and fabrication expertise into more markets.
 Watch our Router Video Here.