Spagco - Parshall Flumes
Spagco Parshall Flumes are constructed from a fiberglass composite constructed of two fiberglass skins with a polymer concrete core. All Spagco flumes have a total wall thickness of 1 ½”. Due to the high moment of inertia of the wall due to the thickness, no stiffeners or other braces are required. The superior strength of the sandwich panel construction allow the flume to act as the concrete form as the concrete trench wall are cast with no need for any internal bracing.
All Parshall Flumes are made to same dimensions established by Dr. Ralph L. Parshall in 1922 and are shown in attached table #1 plus drawings #1 & #2. Spagco Parshall Flumes come standard with two built in gauges. The first gauge is set at a distance of 2/3 of the wall length of the approach side of the flume as measured from the start of the flume throat toward the inbound flow. This first gauge is for measuring the flow into the system. The second gauge is set at a point 2” back from the downstream edge of the throat of the flume. This gauge allows a quick visual check for determining whether the flow is in free flow or submerged flow. Table #2 indicates the flow rate in cubic feet per second under free flow conditions as well as the maximum height at gauge to as compared to the gauge #1 reading for free flow to exist. If the water level at gauge #2 is higher than indicated the incoming water in a submerged flow condition and the chart will have to be adjusted to accommodate that flow. Spagco can also supply threaded inserts or mounting brackets for installing ultra sonic sensors or other flow measuring devices as required.