2" Diam Heavy Duty Flexible Exhaust Pipe (per metre)

Product Information

If required we can offer the same extensive NDT and manufacturing documentation as with our metal expansion joints and pressure vessels. This capability allows us to serve demanding end users in the petrochemical, refining and energy markets with unique custom designed metal hose assemblies. The value of soil load analysis is to arrive at the required pipe strength necessary to build a municipal pipeline of sufficient structural integrity to serve its design life. The design process varies from rigid to flexible pipe, and usually by pipe material also. The second part of this series in the next issue will review current design practices for rigid and flexible pipes with regards to earth loading.

The critical plane is the horizontal plane through the top of the pipe when the fill is level with its top. At critical plane, H=0. During and after construction, if this critical plane settles more than the top of the pipe, as shown for rigid pipe in figure 3a, the settlement ratio is positive (prsd>0). For flexible pipes, figure 3b, the critical plane settles less than the top of the pipe, indicating the settlement ratio is negative (prsd<0). Type 316 Stainless Steel Flexible Hose is available where even greater corrosion resistance is required In designing and optimizing an unbonded flexible pipe structure designation of adequate materials, the correct balancing of pipe structural elements, geometry, and interaction between layers must be considered. We ensure the long-term durability of a Flexibles pipe through a combination of only using symmetrical pressure armor profiles—which contain an absolute minimum of residual stresses after having been applied onto the flexible pipe structure—and a careful preforming of the double-layer cross-wound tensile armor comprised of multiple rectangular steel wires. Chen BH (2005) Experimental study on mechanical properties of oil hose. Master’s thesis, Tongji UniversityIn 1913, and 1930, Marston published his original papers “The Theory of Loads on Pipes in Ditches and Tests of Cement and Clay Drain Tile and Sewer Pipe” and “The Theory of External Loads on Closed Conduits in the Light of the Latest Experiments,” respectively, marking the earliest systematic approach of studying the structural mechanics of buried pipes. Thus was defined the Marston Theory of Loads on buried conduits. While an understanding of pipe-soil interaction is important for the sound structural design of pipelines, it should be noted that the concern for soil pressure on a pipe is limited to empty pipe or gravity flow pipelines where the conduit never flows full. In municipal pressure piping systems, the internal pressure is typically much greater than soil pressure on the pipe; internal pressure essentially supports the soil load when the line is placed into service. The flexible stainless steel hose manufactured at Proflex Hose is suitable for use with both liquids and gases in a variety of intensive applications. As a stainless steel conduit, it is highly resistant to heat and can be used in high-temperature roles, while also being very resistant to corrosion. This corrosion resistance gives flexible stainless steel pipe the ability to survive in tough environments and carry a range of fluids. A tough, resilient and long-lasting material, stainless steel flexible conduit is perfect for use in a wide range of applications. Flexible Metal Hose A positive embankment installation condition, where the pipe is installed underneath an embankment, in shallow bedding, with its top projecting above the surface of the natural ground, is another commonly-encountered scenario for buried pipe design and installation. The loads and shearing forces just discussed for trench conditions also play a key role in embankment conditions. As indicated in figure 3a and 3b, the imaginary vertical planes extending upward from the sides of a buried pipe are the planes along which relative movements are assumed to occur and on which shearing forces are generated.

As a general rule, flexible pipes will deflect at least 2 percent without structural distress. Most flexible pipe material standards allow up to 5 percent deflection. Deflection is limited to 2 percent if the flexible pipe has a rigid lining and coating and 3 percent for a rigid lining and flexible coating. Flexible pipes include steel, ductile iron, thermoplastics such as Polyvinyl Chloride (PVC) and High Density Polyethylene (HDPE), thermosetting plastics such as fiberglass-reinforced polymer (FRP), bar-wrapped concrete cylinder pipe, and corrugated steel pipes. Semi-Rigid Pipe Since it was almost impossible to predetermine the settlement ratio that would develop in a specific case, Marston tabulated it as an empirical quantity, based on the type of pipe material (rigid or flexible), and foundation conditions for rigid pipe and side-fill soil condition for flexible pipe. DIN 3384: Stainless steel flexible hose assemblies for gas applications-safety requirements, testing, markingTectite tube offers installers the flexible installation of plastic with none of the compromises, suitable for use on central heating and potable water. The Tectite classic fitting provides the performance and reliability only metal can; an array of features ensure you leave the job today knowing it won’t cause you problems tomorrow. Yijimei (2014) Application status and prospect analysis of umbilical cord cable in offshore deepwater oil platform [J]. China Shipbuilding, 2014 The hose should not be subjected to twisting; Also, the installation should be such that flexing takes place only in the plane of bending. The flexible metal hose available from Proflex Hose is made to a strict standard, ensuring a reliable, high-quality hose that always performs to the level you require. The core of the flexible stainless steel hose is a relatively thin tube, which is corrugated to allow flexibility in any direction without compromising strength or durability. Around this flexible core, a weave of stainless steel wire is placed, sheathing the interior tube and providing impressive resistance against pressure from inside and out, as well as improving durability and providing powerful protection against physical damage, corrosion and the elements. More than one layer of this braiding may be fitted as necessary, depending on your needs. Flexible Stainless Steel Conduit Applications

From tees to tap connectors, the Tectite classic range includes all the fittings you need to install a high-quality domestic system, and BES can supply all you need. The right pipes and tubes for any job In addition to the importance of accounting for the soil load on buried pipe (dead load), it is also important to account for live loads, whenever applicable, such as moving vehicles (live load) when a pipe is buried under a highway or railroad embankment. One way in which this is done is by use of modified Boussinesq equations, details of which were not discussed in this article.Hong Guo, Yan Qu, Qingzhen Lu, Jun Yan, Qianjin Yue (2011) Structure design of umbilical for deep water subsea production system. In: Proceedings of the 15th China ocean (shore) engineering symposium. Jun 2011 Buried pipe design, then, was inextricably connected to the development of highway systems in the United States. Marston was the first Chairman of the federal Highway Research Board. Our knowledge of pipe-soil interaction, as well as the development of new pipe materials and the improvement of traditional ones, has grown by leaps and bounds since those early days, leading to a multi-billion dollar global pipe materials industry. Another relatively new construction method in buried pipeline construction and rehabilitation is the advent of trenchless technology. Tensile armor– A number of structural layers consisting of helically wound flat metallic wires. The layers are counter-wound in pairs. The tensile armor layers provide resistance to axial tension loads. For pressure hoses with braided reinforcement, the corrugation stress comes mainly from the bending of the hose. Therefore, the corrugation stresses can be controlled by setting a limitation on the bending. In other words, the installation is acceptable if the hose is not bent beyond the limiting radius. Similar to the situation discussed in the bellow expansion joint, the mode of failure of the hose corrugation is due to fatigue. Therefore, the bend radius limitation depends also on the number of operating cycles expected. Most manufacturers provide two limiting radii, one for static applications involving a one-time fit-up installation, and the other for operational movement involving many cycles of intermittent flexing. The whole design and installation process actually ensures that this minimum radius is maintained during the initial layout and throughout the operation. Factors for Metallic Flexible Hose Selection A full selection of fittings and finishes are available from Proflex Hose, including flanges, screw ends, hydraulic hose fittings and other fittings to fit your requirements.

For positive projecting conduits, Marston also determined, initially purely through mathematical reasoning, the existence of a horizontal plane above the pipe where shearing forces would be zero, referred to as the plane of equal settlement. Settlement of interior and exterior prisms above this plane is equal. Marston Load Calculations in Trench Condition Our pipes are designed under rigorous rules based on models of the operational conditions. If desired, they can be constantly monitored by embedded sensors and electrical heating wires into the structure. Our pigging solutions, pipeline products, and structures are designed to interface perfectly with our flexible pipes. There is a great variety of possible end fittings and connections, typically the two end fittings are dissimilar; we can accommodate any requirement as long as the material and fitting are weldable. The most common fitting styles are: Weld end In his analysis of external loads on buried pipe, Marston defined two main types of loading conditions of buried pipes, a ditch conduit (referred to as trench load condition in present day nomenclature), and a projecting conduit (referred to as an embankment condition in present day literature), Table 1.Wei SC, Han Q, Wei XJ (2003) Selection and combination of marine hose reinforcement. Material Report (06):60–63 The range of stainless steel braided hose provided by Proflex Hose are made to be amazingly durable and great in strength. With this form of hose, an external layer of braid is added to prevent the elongating of a tube when pressure is applied. This enables better flexibility and movement for the hose. The basic concept of the Marston Load Theory is that the load on a buried pipe, because of the weight of the column of soil, or central prism, directly above the pipe, is modified by the response of the pipe and the relative movement of the side columns of soil, or external prisms (adjacent to the pipe, between the pipe and the trench walls on either side), to the central prism. The relative movement of the central prism and the side prisms result in shearing stresses or frictional forces, calculated using Rankine’s theory. The allowable bending radius for the hose depends on the type of motion the hose will experience, this is described as: As the corrugated interior tube is seamless, stainless steel conduit is ideal for use with liquids or gasses under pressure, especially when fitted with external braiding. With first-rate corrosion resistance, a stainless steel flexible conduit is also ideal for use in chemically demanding situations – and this combination of factors makes them absolutely perfect for use in the petrochemical industry, or in steelmaking, chemical smelting, the automotive industry the power generation industry and dozens more.