Manholes are an important source of I&I, and municipal managers increasingly recognize the need to plug leaks in manhole chimneys and other potential weak spots. Here is a look at some of the chemical sealants and other sealing systems available from industry manufacturers.Application nozzleThe SPN Series rotary nozzle from RFI Construction Products is a high-speed device for applying grouts, mortars and epoxies to circular surfaces such as pipes, pipe fittings, manholes and shafts. Four-inch to 120-inch inside diameter lining is possible in thicknesses from 0.25 to 4 inches. The rotary head is powered by an integral air motor. 631/752-8899;
