Composite Ring Brick Sewer

A brick sewer which consists of a greater number of layers of brick above the springing line than below the springing line.

Compounding

The process where additives and carbon black are homogeneously mixed with the base polyethylene.

Compressed Air Method

General term which, in trenchless technology, refers to the use of compressed air within a tunnel or shaft in order to balance ground water and prevent ingress into an open excavation.

Compression Gasket

A device which can be made of several materials in a variety of cross sections and which serves to secure a tight seal between two pipe sections (e.g., “O” rings).

Compression Ring

A ring fitted between the end-bearing area of the leading pipe bell and the trailing pipe spigot to help distribute jacking forces more uniformly. A compression ring is attached to the trailing end of each pipe and is compressed between the pipe sections during jacking. The compression ring compensates for steering corrections, pipe misalignment, and pipe dimensional tolerances. Also referred to as a packer.