Pipes costs

Fig. 12. Piperack, piping, and equipment relationships in a petroleum plant. A—E signify dimensions which affect piping cost.

TABLE 9-57 Components of Total Installed Piping Cost... 

The number of flare headers required depends upon an economic evaluation of system combinations that will result in the minimum piping cost. The following steps outline the procedure for comparative estimations ... 

Refrigeration system pipes are sized to offer a lowresistance to flow, since this reflects directly on compression ratio, commensurate with economy of pipe cost and minimum flow velocities to ensure oil return with the halocarbons. 

Four-pipe system This layout uses HW supply and return pipes for space heating (pipes 1 and 2) and chilled-water pipes for space cooling (pipes 3 and 4). Effective building climate control by conventional means is easier with a four-pipe system, but the piping costs obviously are much higher. 

It has already been noted that the only other item that might be affected is the process piping cost. If necessary, the contingency allowance can be increased to account for this. 

Bromberg, I. A Look at an Engineering Contractor s Overhead Costs, Sept. 12,1966, p. 218. Sokullu, E.S. Estimating Piping Costs from Process Flowsheets, Feb. 10,1969, p. 148. 

Solution. From Table 7-2, the pipe cost parameters are... 

You must design a pipeline to carry crude oil at a rate of 1 million barrels per day. If the viscosity of the oil is 25 cP and its SG is 0.9, what is the most economic diameter for the pipeline if the pipe cost is 3 per foot of length and per inch of diameter, if the power cost 0.05/kWh, and the cost of the pipeline is to be written off over a 3 year period The oil enters and leaves the pipeline at atmospheric pressure. What would the answer be if the economic lifetime of the pipeline were 30 years ... 

Low saturation (boiling) pressure at high temperature—to minimize the pressure vessel and piping costs. 

The above objective represents a minimization of the annualized cost which comprises crude oil cost, refineries operating cost, refineries intermediate exchange piping cost, production system expansion cost, and export revenue. The operating cost of each process is assumed to be proportional to the process inlet flow and is expressed on a yearly basis. 

Two general methods have been used to estimate piping costs when detailed flow sheets are not available. One method is to use a percentage of the FOB equipment costs or a percentage of the fixed capital investment. Typical figures are 80 to 100 percent of the FOB equipment costs or 20 to 30 percent of the fixed capital investment. This method is used... 

---