The sliplining procedure is one of the oldest methods in trenchless pipe restoration technology. It’s more of a rehabilitation solution than replacement. In this article, we’re going to take a look at the primary procedure of sliplining .
1. Taking a look at the pipes
There is an initial inspection of the pipes before a sliplining procedure is considered. The reason for the inspection is to determine if the pipeline is suitable for sliplining. You see, there are pipes that can’t be restored through a rehabilitation method. Pipes that are too damaged or have broken joints are replaced instead of restored. If sliplining is a viable solution then the pipes are further inspected. Additional inspection will help find obstructions or clogged segments in the pipeline. A remote CCTV camera is inserted into the pipes to gain visual.
2. Clearing the pipeline
It’s integral in the entire operation to clear and clean the pipeline. It will be easier to integrate the pipe into the old pipeline if there no other obstructions. Digging minor damaged sections may be conducted for a better and smoother pipe insertion. There are many tools that can be used to clear out the pipeline like plugs, buckets, hydro jets, and augers.
3. Fusing the polyethylene pipe with the liner
The polyethylene pipe is fused together with a liner for better insertion. This can be done during clearing the pipes or before the entire operation. There are many methods that can help in mixing the pipe and liner. These are butt fusion technology, extrusion, welding or with gasketed bell and spigot combination. The combination method used will depend on what type of polyethylene used.
4. Excavating access pits
An access pit is needed for the insertion of the pipe liner. In most cases, the manhole or available entry point of the pipe isn’t enough. Creating an access pit is needed if there isn’t any other access point when inserting the pipes. Not all access pits are the same. It will depend on many factors. These factors include the depth of the pipeline, diameter of the old pipe, soil conditions, location of the underground pipeline, and many more.
5. Installing the polyethylene liner
There are a few ways a polyethylene liner can be placed into the pipeline. The popular methods are usually the ‘push’ or the ‘pull’ process. Solid walled— polyethylene pipes can be inserted through pushing or pulling the liner. Pushing the liner into the pipes is the only method for Gasket-Jointed pipes .
6. Adding connection and lateral service.
Inserting the pipes doesn’t end the sliplining procedure. There is 24 hours given to relax the inserted the polyethylene liner. The service and lateral connections are added after the 24-hour allowance. These connections help sewer line to work again without any issues.
7. Inserting terminal connections and stabilise the sewer system
The terminal connections are needed for final adjustments. Connections are double checked in addition in stabilizing the space and entire sewer system. Pressure cables are usually applied in adding terminal connections.