There are 4 items to consider early in the evaluation phase of a project to determine whether or not sliplining is the right solution.
These items are:
1 1. Number
Since sliplining involves pushing or pulling a new pipe through the old pipe, the straighter the existing pipe, the easier the process. Curves can be sliplined, but they must be discussed with the manufacturer of the particular pipe material. In segmental slipliner systems, short lengths of pipe are used to negotiate curves. Each of the joints articulates a small amount to form the curve in segments. In continuous sliplining, the concern is the stress which will be put on the pipe walls.
2 2. Availability of a Location
for an Access Pit:
By the nature of the process, sliplining needs an access pit. The access pit must be located directly above the pipeline. If the project cannot have a small pit, usually 20 feet long by 10 feet wide dug, then sliplining may not be the best solution. In some cases, sliplining can be done from existing access structures and manholes. These situations need to be evaluated on a project by project case.
3 3. Number of Service Laterals
A consideration when deciding whether to slipline an existing pipe is the number of service laterals or other types of connections. Reconnecting service laterals will require access from the outside. This will require a small pit or shaft to be dug at the location of the service. Large numbers of services will make a dig and replace option more economical. Systems for internally locating and restoring laterals are under development. These systems will make sliplining a more trenchless method.
4 4. Bypass Pumping
Segmental sliplining generally does not require bypass pumping as do other rehabilitation systems. Besides the practical aspects of having a bypass pumping system in operation, there are significant savings by its elimination. Practical considerations include potential spillage, pump failure, piping systems for the bypass, noise, and capacity. These items point to bypass pumping as unsafe and dangerous.
By checking these initial items an evaluation of the feasibility of sliplining can be quickly performed.