Piping materials available

Corrosion is simply the destruction or deterioration of a material because of a chemical reaction with its environment (4). Types of corrosion range from rust on an automobile to intergranular cracking of a pipe in a gas well. In addition to its economic impact, corrosion affects our health and safety, the development of new technology, the existence of ancient works of art and even, through material availability, national security ( ). 

Consider Figure 5 again. Bleeder steam line B5 extracts 55351 lbm/hr (6.974 kg/s) at 93.8 psia (0.65 MPa) and 603 F (317 C) from the intermediate-pressure turbine delivering it to a feedwater heater. Steam line B5 was chosen to illustrate the design procedure for two reasons. First, the design has sufficient flexibility there are no extraordinary constraints on the pipe material and size, or on insulation thickness. Secondly, the available energy analysis and unit-cost computations for this power plant, and for steam line B5, have been presented in previous papers (5, 6 ) ... 

Ground coupled heat pumps may now be feasible, largely due to the availability of durable and Inexpensive plastic pipe. Pipe materials such as polyethylene, FVC, and polybutylene have been found to be adequate In some Instances. However, no material standards or recommended design practices exist to facilitate the optimization of the performance, cost and reliability of these systems. 

Until now simplified methods have been available to monitor metal release by metallic pipe materials. In the United Kingdom a sit-and-soak test is available to determine the metal release from drinking water materials. In The Netherlands, copper and lead pipes in combination with water quality are tested in pipe rigs, and in Germany a protocol for testing pipe materials is available (see below). 

Reconstruction of European towns and cities that had suffered wartime destruction constituted massive infrastructure investment and boosted demand for construction materials including utility pipelines. Although iron and steel continued to be the dominant pipe materials the increasing availability of plastics at reducing prices prompted much technical development that created many of the plastic pipe production and application technologies used today. 

If appropriate fittings are not available in the same material as the pipe it then becomes necessary to use fittings in an alternative material and then some care must be exercised in the design of transition connection. For example, before plastic valves which could be welded to PE pipes became available it was necessary to employ metal valves with a mechanical connecting joint. 

The incidents related to failures in proper vessel and piping cleaning are common. However, in today s world there are API guidelines and a CSB Safety Bulletin Removal of Hazardous Material from Piping Systems available which can be very helpful to review equipment chemical cleaning procedures such as ... 

In addition, it is shown that, plastic pipes in the house and out (such as underground), all show good resiliency in the case of earthquakes that beats all other traditional materials available (Valencia Water Company, USA, the California private utility was able to compare the performance of three pipe materials - asbestos-cement, PVC and steel, during the catastrophic Northridge earthquake of January 1994, and found that PVC outperformed the others). Since the Kobe earthquake, which showed the structural weakness of traditional pipes, HDPE pipes are preferentially being used as gas pipes [2]. 

Plastic pipes are available in different lengths, diameters and pressure classes with a full complement of standard fittings, valves and couplings. They are compatible with other pipe materials and they can be specified for either new construction or for system upgrades. Plastic pipes can be repaired easily if for any reason they are damaged. On the other hand, traditional metallic and other pipe and tube installations can be sealed and/or repaired, (i.e., by spray coating of epoxy [2]) by use of polymeric materials. 

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