Plant piping

Valve bodies are also standardized to mate with common piping connections flanged, butt-weld end, socket-weld end, and screwed end. Dimensional information for some of these joints and class pressure-temperature ratings are included in Sec. 10, Process Plant Piping. Control valves have their own standardized face-to-face dimensions that are governed by ISA Standards S75.03, 04, 12, 14, 15, 16, 20, and 22. Butterfly valves are also governed by API 609 and Manufacturers Standardization Society (MSS) SP-67 and 68. 

Piping Estimation The cost of fabrication and installation of process-plant piping appears to range from 18 to 61 percent of the FOB equipment cost as indicated in Table 9-56. This would normally represent about 7 to 15 percent of the installed plant cost and is obviously a significant item. The various available piping-estimation methods are as follows ... 

Boyce, M.P., Chapter 10. Transport and Storage of Fluids-Process-Plant Piping, Perry s Chemical Engineers Handbook, 7th Edition, 1997. 

These techniques have been described previously in the pressure measurement section. Usually, one of the flow-measuring devices and the required instrumentation is incorporated as a part of the plant piping. The choice of technique depends on the allowable pressure drop, flow type, accuracy required, and cost. 

If casing limitations are fixed by user-supplied relief valves, this information should be conveyed to keep the vendor from rating the compressors on other data. Evaluations can be more of a problem if the same design basis isn t universal with all vendors. Startup and shutdown consideration influence various components, shaft end seals, seal system pressures, and even thrust bearings in some instances. The use of an alternate startup gas, or the desire to operate a gas compressor on air to aid in plant piping dryout should be covered. 

Characteristics of Pipe System Failures in Light Water Reactors Nuclear Approximately 100 records of pipe failure rates in a wide variety of failure modes Nuclear Power Plant Piping 114. 

DATA BOUNDARY Nuclear Power Plant Piping... 

The water system layout should provide an adequate supply to all parts of the plant. Piping, pumps, tanks, alves, hj drants, and au.xiliao equipment should follow acceptable stanckirds. 

For an illustration of a portion of a plant piping system (see Figure 2-2). 

Try 1/ -inch (i.d. = 1.61), since 114-inch (i.d. = 1.38) is not stocked in every plant. If it is an acceptable plant pipe size, then it should be considered and checked, as it would probably be as good pressure drop-wise as the 114-inch. The support of 114-inch pipe may require shorter support spans than the 114-inch. Most plants prefer a minimum of 114-inch valves on pressure vessels, tanks, etc. The valves at the vessels should be 114 inch even though the pipe might be VA inch The control valve system of gate and globe valves could very well be lA inch. For this example, use 114-inch pipe, Schedule 40 ... 

No matter how well insulated, buildings will need a continual input of heat to maintain desired temperature levels. The input required will be much smaller in a well-insulated building than in uninsulated ones - but it will still be needed. The same applies to items of plant - pipes, vessels and tanks containing hot (or cold) fluids. If there is no heat input to compensate for the loss through the insulation the temperature of the fluid will fall. A well-insulated vessel will maintain the heat of its contents for a longer period of time but it will never, on its own, keep the temperature stable. 

Some of the ultrasonic systems include ultrasonic transmitters that can be placed inside plant piping or vessels. In this mode, ultrasonic monitors can be used to detect areas of sonic penetration along the container s surface. This ultrasonic transmission method is useful in quick checks of tank seams, hatches, seals, caulking, gaskets or building wall joints. 

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