Slip jacking is a trenchless method of inserting a smaller diameter product pipe into an existing larger diameter tunnel with the flow that has been diverted or bypassed pumped. Unlike sliplining systems that can accommodate live flows during operations, slip jacking uses equipment from pipe jacking methods that do not allow for live flows inside the shaft.
The decommissioned existing tunnel is cleaned and cleared of any obstructions such as tree roots that will prevent the new product pipe’s advancement. A jacking frame is set up in the launch shaft matching the elevation of the existing line. If necessary, a forward shield can be installed with a leading edge to clear debris from the existing tunnel while the pipe is advanced. The annular space is sealed between the new and existing tunnel through ports supplied in the new pipe to prevent groundwater’s future inflow.
Slip jacking is a cost‐effective method to rehabilitate existing underground utilities with trenchless equipment that can also be used with other Akkerman products. Akkerman’s 5200 pump unit and jacking system are ideal for slip jacking as well as tunnel boring, hand mining, shield tunneling, or other pipe jacking operations with minimal additional investments.
For additional information on slip jacking equipment, please navigate to the equipment page or contact our sales representatives to discuss your sales and leasing opportunities today.