With the acceleration of global urbanization, municipal construction needs to bury and replace a large number of pipelines underground. Especially in China, which is developing rapidly, urban people have a strong awareness of environmental protection and require that pavement should not be excavated and grass and surrounding landscape should not be damaged in the project. In the past, China HDPE parts factory during construction, when the sewer pipe was damaged or worn over time, plumbing experts would have to dig and repair each pipe part that needed attention. Repairing pipes in this way is not only costly and labor-intensive, it is also damaging to the surrounding environment. Today, thanks to modern trenchless pipeline technology, it is cost-effective and sustainable to restore ancient pipelines to full service. What is trenchless technology? Trenchless technology refers to a series of underground pipeline installation methods. It is a modern construction technology of laying, replacing and repairing various underground pipelines under the condition of excavation of a extremely minor part of the surface (typically referring to excavation of a limited area at the entrance and exit) through guiding and directional drilling and alternative means without digging the surface. Compared with the traditional trenchless construction method, trenchless technology has the characteristics of no impact on traffic, no damage to the environment, short construction period and significant social benefits. It minimizes disruption to road traffic, lawns and gardens, business operations and other activities. Trenchless pipe laying technology has a wide range of applications. It can cross busy roads, railways, buildings, rivers and lay pipelines in downtown areas. It is widely used in the construction of modern pipelines and the repair of obsolete pipelines in the fields of water supply, drainage, electricity, communication, gas, etc., and can also be applied in the protection of cultural relics and ancient buildings. The application of trenchless technology in polyethylene pipe: PE tube is the most common type of pipe in non-excavation construction, which has been widely used in four common trenchless construction methods, and has been successfully applied in our country. 1. Horizontal directional drilling and pipe laying This is the most common trenchless pipe laying method. Directional drilling is a way to quickly lay underground lines without having to dig a working hole. Its main features are that the drill pipe with wedge-shaped bit can be driven into the ground according to the pre-designed pipe laying, and then in the predetermined direction around the underground obstacles until the destination; the drill bit is then removed and replaced with the appropriate size and special type of return reamer that allows the drill pipe to be pulled back to the desired diameter while the pipe is being pulled back. The line that needs to be paved is also pulled back to the entrance of the drill hole to ensure that the original line is not damaged due to lack of space or friction from cuttings. It has been widely used in telecommunication pipeline, electric power pipeline, natural gas pipeline and water supply pipeline. Advantages of directional drilling: (1) Pipelines of various materials with diameters of 100mm ~ 1000mm can be paved without digging working Wells; (2) A unique drilling system with maximum torque that can handle most geology; (3) the specially designed wedge bit can adjust the drilling direction at anytime to avoid obstacles; (4) The guiding positioning system can be measured to a depth of 30.5m to ensure the accuracy of the construction route; (5) The construction is quick, the maximum distance of one drilling can reach 600m; (6) Suitable for paving all kinds of trenchless engineering pipelines of different materials, especially HDPE solid wall pipe. 2, crack pipe method to replace the original pipe This method is to squeeze the ancient pipe into the surrounding soil after it is broken, and then pull the current pipe into the original pipe position. Normally, gaseous power (elevated pressure air), static power (hydraulic) crack pipe system is used to break the aged pipe, and PE pipe is connected after the cracked pipe head. When the original pipe is broken, the fresh HDPE pipe is laid, so as to achieve the purpose of replacing the original pipe. The advantage of this method is that the diameter of the current pipe can be equal to or even greater than the original pipe that is replaced. The disadvantage is that the original pipe is surrounded by broken ancient pipes when it is inserted into the original pipe, and the original pipe will inevitably be damaged. Therefore, the pipe is required to have excellent damage resistance, wear resistance and cracking resistance. 3. Repair the ancient pipe by intubation This technology involves inserting plastic liners into ancient pipes, which can be divided into "sliding liner" and "fitting liner" according to the outer diameter of the liner and whether the inner wall of the aged pipe is fitted. The sliding lining method is to insert the original polyethylene pipe with an outer diameter slightly smaller than the inner diameter of the original pipe into the original pipe to be repaired, and the gap between the new pipe and the old pipe can be sealed by filling mortar, etc. The fitting liner method is to insert the current plastic liner whose outer diameter is equal to the inner diameter of the old pipe smoothly into the old pipe to be repaired through "reducing diameter" or "folding" and other methods, and then restore the shape of the reduced diameter or folding liner to the original shape by means of natural recovery or pressure heating, so as to achieve the purpose of fitting the inner wall of the old pipe. The fitting liner can bear the internal pressure together with the ancient pipe. This method is only suitable for the repair of large diameter pipeline, the pipeline has a large loss of cross section. 4. Pipe laying with pneumatic spear Trenchless pipe laying is carried out by means of impact with spear type drilling tool. The driving mode is mostly pneumatic (can also be hydraulic), known as the pneumatic spear pipe laying method. The pneumatic spear relies on the friction between the hammer and the soil layer to support and move forward. Under the impact, the hole is formed by extrusion. The pipeline to be laid is connected behind the pneumatic hammer and is laid along with the hammer moving forward in the soil layer. The PE pipe can also be dragged back into the hole after the pneumatic spear is drilled. This method is simple, easy to operate, high efficiency and low cost. The length of pipe laid is typically within 40m, and the diameter of pipe laid is 40-200mm. It is suitable for soil layer. The latest tools have reciprocating chisel heads and can be used in gravelly soil layers. The main advantages of trenchless technology Save time and interruptions The traditional excavation process takes longer than alternative pipe installation or repair methods. Ditching the road means the work has to be done at night to reduce traffic disruption. With trenchless installation and maintenance, you can speed up the process of dealing with broken pipes, allowing tunnelling under the road even during heavy traffic. Since there is no need to employ large technicians, traffic controllers, excavators, horticulturists, etc., trenchless technology is generally the most cost-effective option. Trenchless methods also minimize equipment and tool requirements and reduce your labor costs. A less obtrusive and environmentally friendly alternative causes minimal damage to the surrounding landscape due to extremely limited excavation with trenchless techniques. Trenchless units also do not require structural modifications, such as wall removal or pavement renovations, allowing you to install plumbing infrastructure as easily as possible. Make HDPE pipe more durable HDPE pipes offer greater flexibility, damage resistance and leak resistance than regular PVC, steel or concrete pipes. Use HDPE piping with trenchless technology to provide you with unmatched durability piping.