{"id":1508,"date":"2018-09-23T15:56:16","date_gmt":"2018-09-23T12:26:16","guid":{"rendered":"http:\/\/afzir.com\/en\/?page_id=1508"},"modified":"2026-07-23T12:34:45","modified_gmt":"2026-07-23T09:04:45","slug":"repairing-pipes-tanks","status":"publish","type":"page","link":"https:\/\/afzir.com\/en\/structural-retrofitting\/repairing-of-pipes-and-tanks\/","title":{"rendered":"Repairing of Pipes and Tanks"},"content":{"rendered":"

Pipes<\/h1>\n

Repairing\u00a0of Large\u2010Diameter Pipes<\/h2>\n

More than 6 billion gallons (23 million liters) of water are lost daily due to leaking pipes (ASCE<\/strong><\/a>\u00a02009). Additionally, a large number of pipes in water distribution networks and oil and power industries are badly deteriorated and require repair or strengthening. These pipes are usually pressurized, and deterioration of reinforcement results the hoop stresses to exceed the capacity of the pipe. When unattended, the consequences of such failures are grave and can leave entire neighborhoods under water (Johnson and Shenkiryk 2006) or force emergency shutdown of plants. A common strengthening approach in the last decade has been to apply one or more layers of carbon fabric inside the pipe. The author has been involved in such projects in a major U.S. nuclear power plant since 1988. The fabrics\u00a0provide adequate strength in the hoop and longitudinal directions. While very effective, the time associated with the wet layup method has been a major drawback to this system.<\/p>\n

Super laminates significantly reduce the construction time. The flexibility of the laminates allows them to be wrapped around cores that are 12 inches (300 mm) in diameter for ease of transport into pipes through manholes that are typically 24 inches (600 mm) in diameter (Fig. 3). The ability of super laminates to conform to the diameter of the pipe, i.e. \u201cone size fits all,\u201d is a major time and money saving attribute of this system for contractors. Most of the current products on the market that can be used as liners to repair or strengthen pipes have a fixed diameter and cannot be applied to different size pipes.<\/p>\n

Installation involves applying a thin layer of\u00a0epoxy putty<\/strong><\/a>\u00a0to the back of the supper laminate and pressing the laminate against the pipe surface. No effort is required to remove the air bubbles as the supper laminates are pre\u2010cured. In fact, depending on the diameter of the pipe, the elastic memory of the coiled super laminate may cause it to expand inside the pipe (like a loaded spring) and snap against the host pipe with little effort. Continuity of the super laminate rings is achieved by adequate overlap lengths in the hoop and longitudinal directions. Thus, unlike ordinary laminates that are unidirectional, super laminates do allow strengthening of the pipe in both hoop and longitudinal directions with a single application.<\/p>\n

Not only\u00a0super laminates<\/strong>\u00a0are installed faster than fabrics, it is possible to include multiple layers of fabric into a single laminate, further reducing construction time. When steel pipes require strengthening, to avoid galvanic corrosion, a layer of glass fabric is typically applied to the surface of the pipe before any carbon fabric is applied (ACI 440<\/a><\/strong>, 2008). This protective layer can also be included in the super laminate, resulting in even further time savings. Thus instead of saturating and applying three layers of fabric to the pipe, the strengthening can be achieved by installing a single layer of super laminate. This can reduce the construction time by as much as 80% in many jobs. Such significant reduction in repair time makes many larger retrofit projects possible, where the water authority, for example, could not afford the long shutdown time required for conventional repairs.\u00a0 Afzir Company provides a complete line of products for pipeline renovation that can be found at\u00a0www.sazpad.com\/afziren\/.<\/p>\n

Save time and money by asking the experts at Afzir how we can help solve all your problems with buried pipe, however big or small.<\/p>\n

Advantages of repair of pipes with FRP include:<\/p>\n