In 1960, our company built the first filament winding machine to produce FRP mine ventilation duct, and started an entirely new industry.  These first non-metallic ducts were a big improvement over the heavier and conductive metal ducts.  Our mine and tunnel ventilation ducts maintain a MSHA approval as a Class 1 rated duct system, and have been used in mining and tunneling applications now for 54 years.  Spunstrand Inc. has a variety of duct configurations available to suit the needs of most any situation our customers may encounter.

MSHA Mine DuctPhysical Data

Construction: Fiberglass reinforced fiberglass plastic air duct for mining and tunneling applications is constructed using the filament winding process.  Continuous fiberglass strands are impregnated with polyester resin and precision wound in a crisscrossed helical pattern.  The resin is specifically formulated for mining applications to maximize toughness and durability and is highly resistant to both alkaline and acidic conditions.

Shapes and Sizes:  Ventilation duct is available in round as standard and also oval and rectangular.  Standard lengths are 10’ or 20’ although any length is available within shipping limitations.  Standard size diameters range from 2” through 72”, and larger can also be manufactured upon request.

Standard Accessories:  D-Ring / Hangers and Bell & Spigot Connections with integrated gaskets for a low leakage seal.

Standard Fittings
Spunstrand Mine Duct Standard Fittings
Since 1960,  Spunstrand Inc. has manufactured filament wound fiberglass rigid ventilation duct for the mining and tunneling industries.  Our production plant is located in Wallace, ID and our corporate / sales office in Post Falls, ID. All Duct Receives MSHA Labels.