CORRECTION
During the makeup of “Straight Line Hydraulics” (FE, April 1984, page 30), several errors were made that should be brought to the readers’ attention:
- Figure 1 (friction loss) was not reproduced to scale, and, therefore, the chart is inaccurate.
- Back pressure (or forward pressure) is determined by multiplying the elevation change (in feet) from the pump to the nozzle by 0.434; not by the “duration” as the copy reads in the last column of page 33.
- In example 4 (page 38), the sentence on total friction loss should read, “Total friction loss is then read directly from the total friction loss line. This graph thereby eliminates the need to multiply the friction loss per 100 feet by the number of 100-foot sections in the hose layout.”
- The solutions to example 5 (page 38) were inadvertently omitted from the printed chart (figure 3). However, using the information learned in the article, the reader should be able to complete the chart.
