Threading

The process of installing a slightly smaller pipe or arch within a failing drainage structure.

Throttle

ControlsPart of the microtunneling system that allows synchronized excavation, removal of spoils, and jacking of pipe to balance forward movement with excavation so that ground settlement and heave are managed. power, speed.

Thrust

Force applied to a pipeline or drill string to propel it through the ground.

Thrust Block

An engineered structure, located between the jacking frame and the shaft wall, that distributes the jacking force developed by the hydraulic jacking frame over a large surface area to the ground behind the back wall of the shaft.

Thrust Block Pin

See DogsMoveable protrusions in the thrust block that engage holes or blocks in the track..