Carbon steel pipe costs

This equation says that for a given set of cost data the economic velocity is independent of the mass flow handled and dependent on only the. fluid density and the friction factor. More thorough analyses and far more complicated cost equations lead to substantially the same conclusion. For example, for schedule 40 carbon-steel pipe, Boucher and Alves [16] give the data shown in Table 6.4. 

If in Exampl 6,17 the fluid were water contaminated with hydrofluoric acid, we would have to use a special corrosion-resistant pipe. Suppose that this pipe had a purchased cost PP exactly 10 times that of carbon-steel pipe. What would be the economic pipe diameter, pressure drop, and pump horsepower ... 

A refinery is constructed largely of plain carbon steel, which is easily cut and welded. It is the lowest cost metal available. Thus, most refineries will stock a wide variety of carbon steel piping and accessories. One should not expect that the refinery maintenance division will be able to fabricate... 

If the pipelines are located in deep water or inaccessible places, maintenance and/or replacement of pipes and clean-up of oil spills is difficult and expensive. The use of expensive stainless steel or other alloys is not a viable solution due to the required capital costs, which are not economically feasible in many cases. Hence the strategy to combat corrosion problems is to use carbon steel pipes, but reduce and, if possible, prevent the rate of material losses. An important method of corrosion reduction practiced in the oil and gas industry is the use of corrosion inhibitors. The inhibitors act by bonding to the metal surface and forming a protective film. The performance of the inhibitor depends on the metal surface, the inhibitor composition, and fluid flow conditions. Some of the inhibitors are not effective because of the multiphase flow conditions in the pipelines. When selecting an inhibitor, it is essential to know its effectiveness in the specific service environment. Detailed knowledge of the metal surface conditions, the operating temperature and pressure, the fluid properties, the solution pH, and the multiphase flow conditions is essential. 

The wall thickness selected varies with the service and material. Carbon steel coils are often made from schedule 80 or heavier pipe to allow for corrosion. When stainless-steel or other high-aUoy coils are not subject to corrosion or excessive pressure, they mav be of schedule 5 or 10 pipe to keep costs at a minimum, altliougli high-quahty welding is required for these thin walls to assure trouble-free seiwice. 

The estimated cost of the pipes, per unit length is schedule 40 carbon steel 3 ( 5), schedule 80 carbon steel 5 ( 8.3), stainless steel (304) schedule 40 15 ( 24.8). Installation and fittings for all the materials adds 10 ( 16.5) per unit length. 

For instance, equipment made of monel generally costs 6.5 times as much as the same item constructed of carbon steel. If 25% of the equipment purchased for a plant were made of monel, this would increase the equipment costs by 237%, and the factor cost estimate would be 2.37 times that for a plant constructed of carbon steel. This is unreasonable, since the cost of buildings, roads, wiring, piping utilities, insulating, and instrumentation are independent of the materials of construction. In fact the only major changes would be in the process piping, which,... 

According to the vendor, the capital costs for the treatment system include a 200-actual cubic-feet-per-minute (ACFM) vacuum pump, two transfer pumps, a carbon steel knockout pot, and associated instrumentation and piping. Operation and maintenance costs for the system include estimates for additional granular activated carbon (GAC) units, liquid- and vapor-phase analysis, weekly monitoring, electricity, and routine maintenance. These costs vary, depending on the monitoring requirements, contaminant concentrations, and other variables (D13124Y, p. 492). 

Cost and installation time for carbon-steel welded pipe and fittings. 

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