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Packaged Metering Manholes
Packaged Metering Manholes (PMM) make it safe and convenient to measure underground pipe flows, all in a factory-integrated, watertight, and corrosion-resistant package.
PMM components include:
- High-strength fiberglass manhole tube
- Flow device (flume, weir, or mag meter)
- Integrated cover
- Watertight base
- Fiberglass / stainless steel access ladder
- Wiring / tubing coupler
- Inlet / outlet piping
PMMs are very versatile and can be combined with other manhole units for a variety of customized solutions. Available in diameters from 48- to 96-inches [1.22 to 2.44 m] , depths up to 35-feet [10.7 m], and in (5) different top styles, PMMs are highly customizable.
Installation of PMMs is as straightforward as dig it, drop it, done! Because PMMs are made with fiberglass, compared to precast concrete manholes they are:
- Only 1/10th the weight, yet incredibly strong.
- Much longer lasting because they are corrosion resistant.
- Less worrisome when it comes to inflow because they are made from a single, watertight piece.
- Flexible enough to factory integrate a range of flumes, weirs, or mag meters.
- Factory integration / single-source responsibility.
- Less expensive over time because there’s no need for regular inspection, maintenance, or repair to keep everything in good working condition.
Depending on the depth of a manhole, seeing inside can be a challenge. All Openchannelflow PMM tubes are smooth inside and a light tan color to help maximize visibility.
While most PMMs ship as a single piece, those of unusual depth or that integrate large measurement devices might ship in two or more pieces.
Suit your site needs by selecting from a variety of top styles:
- Domed Fiberglass Tops, the most popular choice, is commonly used for grassy non-traffic areas.
- Aluminum Covers, which are typically used for pedestrian walkways and non-traffic or low-profile installations.
- H-20 Traffic Reducers for areas with traffic, like parking lots, loading docks, and warehouse floors.
- Grating Tops where fiberglass or stainless steel grating covers the manhole opening.
- Open Tops for sites already covered with a shelter or other access-restriction measures.
Make the most of PMMs with a variety of accessories that help with air circulation, depth adjustments, equipment or mounting panels, storage, work surfaces, and more.
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Let’s bring your PMM project to life.
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LOCATIONS IN ATLANTA, GA & BOISE, ID