Final answer:
In the severe environments of refinery services, pipes made of carbon steel, stainless steel, or alloy materials are commonly used. The size of the pipe, such as 4-inch, 8-inch, or 16-inch, depends on the specific requirements and economies of scale in the chemical industry.
Step-by-step explanation:
In severe refinery services, such as those involved in the chemical industry, selecting the appropriate type of pipe is crucial due to the harsh conditions they must endure. The pipes used in these conditions are typically made from materials that can withstand high temperatures, pressures, and corrosive substances. Common choices include carbon steel for its strength and durability, alloy steels like stainless steel for their resistance to corrosion, and sometimes even more exotic materials like duplex stainless steels or nickel alloys, depending on the specific requirements of the service environment.
Pipe dimensions are also important: 4-inch pipe, 8-inch pipe, and 16-inch pipe sizes are mentioned. The larger pipes, such as the 16-inch variety, are often employed for their economies of scale, as larger diameters generally provide a more cost-effective solution for the transportation of fluids over long distances. This is supported by data found in references such as Table 7.15 Comparing Pipes: Economies of Scale in the Chemical Industry. It's essential to balance the pipe size to maintain efficient flow rates, minimize pressure losses, and mitigate risks associated with high flow velocities, which can lead to issues like erosion or vibration.