The Plasti-Fab fiberglass reinforced plastic (FRP) PMM was an industry first and remains the most complete and easy-to-install flow measurement package available. Plasti-Fab produces superior quality PMMs by maintaining complete fabrication in-house using only quality glass and resin with no fillers. The manhole barrel is carefully spindle-wound to a minimum ½” thickness. The manhole bottom is molded with a dual-layer to prevent oil canning and provide a flat installation surface. The manhole top is either cone shaped for H-20 loading, molded FRP lid with hinge and hasp, or with water/gas tight hatches. Plasti-Fab fabricates the flume on a mold that ensures precise throat dimensions for accurate flow measurement. On manholes 4’ and deeper Plasti-Fab makes FRP ladders with rungs that have non-slip traction surfaces and internal stainless steel safety bars. All components are glassed in to provide one integral piece that is structurally strong, lightweight, watertight and corrosion resistant to salt water, ground water, corrosive soil conditions and commonly encountered industrial chemicals.

Key Features

  • Composite FRP is extremely resistant to chemicals, saltwater, corrosive soils, ground water and electrolysis
  • Weighs only a fraction of concrete and steel structures
  • Strong – FRP is pound-for-pound much stronger than steel
  • Flumes with precise throat dimensions for accurate flow measurement
  • Premium grade Isophthalic white gel coat interior to resist bacteria and maximize illumination for safety, and gray exterior Minimum 1/2” wall thickness 48”, 60” and 72” diameter barrels standard – custom sizes available
  • Ladder, SS US brackets, and bubble tubes all designed/manufactured in house.