The high density polyethylene liner installation method can be passed into the existing pipe using two techniques. However, both techniques are sometimes necessary to speed up project stages. Push and pull techniques are the most common in this area and are used to hold the liner in place. In the push technique, for watertightness, a jointed profile pipe must be introduced. Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get an original essay This method includes some arrangements like a cable and a winch. The winch arrangement with the cable pulled into the existing pipe for the sliding liner. The cable is tied with the segment on the other side and the cable with the polyethylene liner should be pulled through the existing or host pipe using a winch. The cable is fixed with this arrangement to place the traction method in the correct position. To facilitate this pulling technique, a pulling head is required to secure the cable. There are different types of draw heads available in the market. Types may vary from project to project depending on the nature of the working conditions and site environment. It also depends on the project budget, especially during the installation process. Among them, the tip liner fixed with a main center bolt on one side and a liner on the other end is the most elegant pull head. A steel pull head is connected to the liner using a few bolts. The main purpose of this head is to ensure a uniform load on the cladding wall. The tapered shape of the pull head makes it easier to pass the new pipe through the host pipe. It also adjusts the slight deflections of the coverings. The diameter of this head must be the same as the diameter of the liner or smaller than the outside diameter (OD). This helps pull the hose smoothly when inserted into the host. Due to the tensile process, elongation may occur in the polyethylene liner. For this reason, it is recommended to leave the coating for at least twenty-four hours rest after stretching. The polyethylene liner must be extended 3-5% more than the existing tension to hold the safe due to the shrinking instinct when returning to its normal position (PPI, 2008). In the case of large diameter and heavy welded joint connection liner, this process may not work properly, even on the longer pipeline system. A curved strap is installed around the wall of the liner to help push it into the host. A construction vehicle such as a backhoe or tracked excavator is used to pull the pipe and push it in the correct direction through the pipe. Sometimes other equipment is used to push the coating. The vehicle hits the pipe after it has been connected to the belt. The strap must be put in place after each stroke. The strap is installed manually. The whole process can be completed using the combination of a front loader and a bulldozer. In this process, a sealing pipe is used to create the appropriate place and ensure watertightness. This system does not require any cables or hoists to push the covering through the existing system. However, due to the nature of the project or other circumstances, sometimes push and pull techniques must be applied simultaneously. This technique is most effective when the polyethylene liner is pulled through a large diameter host requiring traction instrumentsheavy. The speed of the push or pull flow is not the same throughout the system. The flow velocity when positioning the pipe in the system is different from the flow in the pipe as it moves through the host. It is recommended that the flow velocity be maintained at a level throughout the system that does not exceed 50% of the pipe capacity. When the liner is placed in the host annulus, provide sufficient flow to transport the liner. At the end of the liner system, upstream blocking flows must be controlled to prevent flooding. Pumping station, flow control equipment, diversion system can mitigate and control the flow system during this technique. There are different types of methods for connecting laterals and home service with the cladding. Connection types depend on the properties of the coating and the side line. When the liner passes through the host line, restoration work begins after a while. As polyethylene has the instinct to expand by pushing or pulling and return to its original position when at rest, it is for this reason that restoration work must be started after 24 hours of laying the covering . Pressure pipe connection made with a pressure pipe. This type of connection requires the ability to withstand all the pressure. A polyethylene branch saddle is placed on top of the liner hole that connects to the lateral line. The connection is made using tees or side wall connection bypass saddles with connectors. Sometimes coil parts are inserted using an electrofusion process. The existing pipe is removed from the connection place to connect the laterals. When connected to the laterals with HDPE, the line joint must be fixed using a wrap-around saddle. In gravity pipelines, a stainless steel strip is used and placed on the connection point of the liner with a joint. The saddle base and liner were then welded to confirm the integrity of the joint. Next, a flexible fitting is used to connect the service side to the new polyethylene pipe. The service saddle method is common in gravity pipelines where steel gaskets and clamps are used. Reconnection of new valves and existing pipe at the end of the project: Reconnection with the existing pipe is the final step of the sliding liner process where the connection is made. using fittings and flanges. Reconnection of the pipe system can be carried out either by thermal fusion or by mechanical connections. The connection must be made in such a way as to reduce the point load at the joint. There are different types of techniques that reconnect the system and confirm the continuation of the existing pressure flow. Connection methods may vary depending on the diameter of the system pipes. In pressure pipe networks, the connection is made using certain specific accessories. Fusion technology is used to reconnect the pipe under pressure. There are three methods in fusion technology commonly used to connect the coating to the existing system. Besides butt, saddle and socket fusion, the electrofusion method is also used using couplings and saddle fittings. The fusion system bonds the coating and existing pipe surface using heat at a specific temperature and force. This method keeps the joint area structurally sound and provides protection against leaks. The system is ready to operate as soon as the.