Sewers invert

The divided areas should be provided with sewer boxes or catch basins. The separate sewer systems are now to be connected to the properly classified sewers. Sewer box or catch basin outlet connections may be at the bottom or side depending upon the sewer invert limits (see Figure 8-3). The term invert refers to the elevation at the bottom inside surface of the sewer pipe. 

Systems that are exposed to excessive turbulence of anaerobic wastewater and a potential increased release of hydrogen sulfide. Systems with a risk for increased turbulence are inlet structures, drops, cascades, sharp bends and inverted siphons. As an example, changes in the flow regime from a pressure pipe into a gravity sewer may give rise to the release of hydrogen sulfide. Corrosion of the sewer pipe wall is often pronounced near the daily water... 

Example 3.7 (a) Design a Parshall flume to measure a rate of flow for a maximum of 30 cfs. (b) If the invert of the incoming sewer is set at elevation 100 ft, at what elevation shonld the invert of the ontgoing sewer be set ... 

The invert elevation of the outgoing sewer in Problem 3.17 has been set at 99.44 ft. At what elevation is the invert elevation of the incoming sewer set ... 

The corrosion of concrete sewer pipe is not a direct result of the presence of hydrogen sulfide gas in the headspace above the water rather the primary mechanism of corrosion is caused by the presence of Thiobacillus bacteria, which reside on the invert of the pipe see Figure 10.7. This genus of bacteria has the ability to oxidize hydrogen sulfide gas to form sulfate, which results in the formation of sulfuric acid see reaction (10.11) ... 

CO = CLEAN OUT RL = ROOF LEADER SB = SEWER BOX CB = CATCH BASIN MH = MANHOLE DH = DRAIN HUB FV = FLAP VALVE -0= INVERT... 

Plot Plan Layout Aid. The plot plan will be a major aid in the design and layout of the various sewer systems. It will indicate the locations of all the various pumps, exchangers, tanks and towers. It will also indicate the extent of paved areas, roadways, undei ound utilities (water and electric) and the locations and inverts of the various sewer tie-ins to the sewer mains at the battery limits. 

Invert. The invert of the sewer inlet and outlet at a catch basin or manhole should be at the same elevation when both inlet and outlet sewer mains... 

As the Invert elevations of the main at the sewer boxes are confirmed, the actual elevations are recorded on the orthographic piping plan drawing, which is shown in Exhibit 13-7. 

As the details for each sewer box become available (e.g., main inlet and outlet sizes and invert elevations, auxiliary inlet elevation, top and bottom elevations, and the diameter), the information is recorded on a sewer box schedule, as depicted in Exhibit 13-15. This... 

The initial layout of any oily or storm water underground piping system usually takes place after the preliminary plot plan is generated. Even though some equipment locations may be tentative, the plant layout designer can begin to spot the oily water and storm water mains, locate sewer boxes, and establish the invert elevation of these systems at each end of the unit. 

Invert elevation This term, usually associated with any underground line, refers to the elevation of the inside bottom of the sewer line, as shown in Exhibit 13-1- Because of the wide range of materials used in drainage piping systems with varying wall thicknesses, it is the constant that is ased to set the elevation on construction drawings. 

Position nozzle into invert of sewer pipe and tie off tiger tail. Use mirror or flashlight if needed. Reset reel counter to zero. 6. Physical - Struck by hiah pressure nozzle head / Noise / Debris from back pressure. 6. Tiger tail may be used to position nozzle into the invert. Ensure nozzle is completely in the pipe before applying minimal pressure. ... 

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