One tough PUPI.

Products // Substation

Fiberglass vs. Steel or Wood

PUPI® fiberglass beams and switch bases are ideal for use in substations and transformer banks. PUPI® fiberglass products are proven to be a superior material for supporting electrical conductors, switches and other electrical equipment. Primary advantages over steel or wood:

  • Engineered material delivers consistent performance that doesn't diminish over time.
  • Excellent electrical insulating properties reduces the risk of shorts and outages.
  • High strength-to-weight ratio for light weight assemblies and easy handling.
  • Maintenance-free construction. PUPI® products never shrink, rot or rust.
  • PUPI® order leadtimes are often much shorter than other suppliers.

Not all fiberglass products are created equal

Unique PUPI® product features make us the leading brand of fiberglass crossarms and braces in the electric power industry. These same features make for superior substation products:

  • SunGUARD® UV Resistant coating is thermally-bonded to all PUPI® products to resist the damaging effects of sun and weather – for at least 60 years in any environment! SunGUARD UV® resistant coating eliminates the risk of blooming and other surface damage.
  • TorqueGUARD hole reinforcing bushings increase bolt hole strength and prevent damage due to over-torqued bolts.
  • PUPI® has over 20 years of experience supplying fiberglass crossarms to electric power utilities worldwide. GEOTEK, the producer of PUPI® crossarms, has over 40 years of experience in the pultrusion of fiberglass structures for outdoor applications.

Designed to fit your needs

Our engineering team is experienced and ready to design PUPI® solutions for your substation or transformer bank needs. Configurations are available to support nearly any application:

  • Crossarms, switch bases, braces, equipment mounts
  • Virtually any length or drill pattern is possible
  • Numerous profile dimensions are available, including:
    • 2" X 4"
    • 3-5/8" X 4-5/8" standard and heavy duty
    • 3" X 4"
    • 4" X 4" standard and extra heavy duty
    • 4" X 6" heavy duty
    • 5" X 5"
  • Factory pre-drilled, or easily drilled on site
  • Custom-designed attachment brackets are available
PUPI® Pultruded Fiberglass Beam Properties:
Tensile Strength: ASTM D638 85,000 psi
Tensile Modulus: ASTM D638 5,500,000 psi
Flexural Strength: ASTM D790 95,000 psi
Flexural Modulus: ASTM D790 3,800,000 psi
Compressive Strength: ASTM D695 60,000 psi
Perpendicular (1/4" thick) ASTM D149 200 volts per mil
Parallel: ASTM D149 167 volts per mil
Specific Gravity: ASTM D792 1.86
Water Absorption: ASTM D570 <1.0% max
Heat Distortion Temperature: ASTM D648 >180C
Flammability: ASTM D636 Nonburning
Color:   Grey or Brown


» Download Sell Sheet