Pipe Fittings

Pipe Fittings In a steel plant there are large numbers of pipe networks. These pipe networks use a large number of pipe fittings. These pipe fittings are of various types, shapes and sizes. Pipe fittings allow pipes to be joined or installed in the appropriate place and terminated or closed wherever necessary. They can be expensive, require time, and different materials and tools to install. They are an essential part of piping systems. There are thousands of specialized fittings manufactured. Each type of pipe or tube requires its own type of fitting, but usually all pipe fittings share some common features. The basic purpose of using pipe fittings in pipe systems is to connect the bores of two or more pipes or tubes. Pipe fittings are used in piping systems normally (i) to connect straight pipe or tubing sections, (ii) to adapt to different sizes or shapes, (iii) to branch or re-direct the piping system, (iv) if necessary to provide a jointing method if two dissimilar piping materials are used in the one system, and (v) for other purposes, such as regulating, measuring or changing the direction of the fluid flow or to connect up threaded pipe and equipment. They are also used to close or seal a pipe. Fittings for pipe and tubing are most often made from the same base material as the pipe or tubing being connected, e.g., stainless steel, steel, copper or plastic. However, any material that is allowed by code may be used, but must be compatible with the other materials in the system, the fluids being transported, and the temperatures and pressures inside and outside of the system. Fittings (especially uncommon types) require money, time, materials, and tools to install, so they are not a trivial part of the...

Production of Seamless Pipes Jul26

Production of Seamless Pipes...

Production of Seamless Pipes  Pipes are either seamless or welded. The manufacturing processes for seamless pipes were developed towards the end of the nineteenth century. In spite of many earlier tests, trials and technologies, the invention of the cross roll piercing process by the Mannesmann brothers towards the end of the 1880s is widely regarded as signaling the commencement of industrial scale production of seamless pipes. In the cross roll piercing process, the roll axes were arranged parallel to the stock axis but an angle to the stock plane. With the rolls rotating in the same direction, this arrangement produced a helical passage for the stock through the roll gap. Moreover the exit speed was slower by about the power of 10 than the circumferential speed of the rolls. By introducing a piercing mandrel arranged in the roll gap, solid round materials could be pierced to produce a hollow shell in the rolling heat by the action of the cross rolls. However, it was not yet possible to produce pipes of normal wall thicknesses in usable lengths by the cross piercing process alone. It was only after development and introduction of a second forming process namely ‘the pilger rolling process’ (again by Mannesmann brothers), it became possible and economically viable to produce seamless steel pipes. The pilger process also constituted an unusual and innovative technology in that the thick walled hollow shell was elongated to the finished pipe dimension by the discontinuous forging action of the pilger rolls (or dies) on a mandrel located inside the hollow shell. Presently seamless pipe is made from round billet, which is pierced through the center to make it a hollow shell and then rolled or extruded and drawn to size. The seamless pipe manufacturing process consists of...