Specifications piping

In order to coordinate the process flowsheet requirements with the mechanical piping specifications, Line Schedules are prepared as showm in Figure 1-24A through D. The complete pipe system specifications are summarized by codes on these schedules refer to paragraph on Working Schedules. 

Figure 1 -26 (continued). Partial presentation of piping specifications for a specific process service. By permission, Borden Chemicals and Plastics, Operating Limited partnership. 

Based upon information from the field tour and knowledge of facility piping specifications, the planner will have most of the data to plan this job. He should already know the pipe size, insulation and material requirements (seats, bonnet, gasket, stem seals). However, he does not know the extent of damage, if any, to the ball. 

Detailed engineering equipment specifications piping specifications instrument specifications electrical specifications control specifications construction specifications detailed engineering data for equipment, piping, instruments, controls, electrical, constructions etc. layout Hazop, Dow F E Index, Mond Index, Fault tree... 

Hydrostatic test pressure (TP) shall be limited to the pressure calculated per para. IP-10.7.2. The maximum testing interval shall be 10 years. Inline examination is normally applied to pipelines or buried piping specifically designed for this type of assessment and should be a requirement for piping systems only when the piping is specifically designed for inline examination. 

F = design factor obtained from Table PL-3.7.1(b)(6)-l or Table PL-3.7.1(b)(6)-3 as applicable, depending upon the fracture control option specified in (b) below used in the design. In setting the values of the design factor, F, due consideration has been given and allowance has been made for the various underthickness tolerances provided for in the pipe specifications listed and approved for usage in this Code. 

Do piping specifications meet chlorine/sulfur dioxide requirements for the service ... 

Typical of the many thousands of items that are standardized in the field of engineering are limitations on the sizes and wall thicknesses of piping, specifications of the compositions of alloys, stipulation of the safety factors applied to strengths of construction materials, testing procedures for many kinds of materials, and so on. 

Piping system changes occur frequently within major chemical plants. This section covers incidents involving piping changes in which piping specifications were not strictly utilized. 

Failure to Follow Piping Specifications as Piping Supports Are Altered... 

The small amount of maintenance required to remove the troublesome spring hangers was not considered a change, because the team did not understand the specifications. Trevor Kletz has often said, People don t know what they don t know. Since people do not know (and cannot always remember) piping specifications, all specifications must be available and kept up-to-date (See Figures 8-6, 8-7, and 8—8). 

The original project installed 3-inch (7.6 cm) Teflon-lined valve bodies and Teflon-lined plugs. Some of the supervisors seem to remember that the original valves were very stiff to operate. It is believed that well-meaning individuals requested easier operating valves, and no one worried about reviewing the plant specifications which were not always up-to-date. Even if piping specifications were consulted, this 3-inch (7.6 cm) branch fine on a 24-inch (61 cm) line was itself a plant modification that was not properly authorized. 

API specification 5L is currently the principal line pipe specification, it combines the previous API 5L, 5LX, and 5LS. The selection of a grade depends on the strength-to-weight ratio and the pumping costs. ASTM specifications (e.g., ASTM A381) are often used for compressor station pipe, particularly for extruded... 

For control valves and other areas of high-turbulence (velocity 8 ft/s [2.5 m/s]) (I e, downstream of control valves, rich carbonate inlet of carbonate regenerator, reboiler tube sheet, and baffles), use type 304 SS plus i/32 in, (1 mm) CA Do not use miters long radius elbows are preferred. See piping specifications for other limitations on miters. 

Investigators determined that a carbon steel section of 6-inch (150 mm) line was installed in an area in which specifications required corrosion-resistant 5-percent chromium—1/2-percent molybdenum (generally called 5-chrome) alloy piping. In a process plant like a fluid coker, the materials used are a mixture of carbon steel and other steel alloys. Apparently, the welder and the maintenance crew, who previously repaired this piping some time ago, were not aware of the piping specifications. Apparently, they did not realize that if a material like carbon steel was installed in an area requiring 5-chrome alloy piping, erosion or corrosion could cause failure. 

The Dow Chemical Company recommends canned-motor pumps or magnetic-drive pumps for phosgene service. Phosgene is an example of an extremely hazardous material. These pumps should have a secondary containment such that failure of the can does not create a phosgene release. The secondary containment should meet pipe specifications for pressure or relieve to the scrubber system in the plant. These pumps must have automated block valves on the suction and discharge. Operation of these valves should be managed such that the thermal expansion does not damage the pump. 

E = purchased-equipment cost = purchased-equipment labor cost /j. = specific material unit cost, e.g., fp = imit cost of pipe — specific material quantity in compatible imits fy = specific material labor unit cost per employee-hour M[ = labor employee-hours for specific material fe = imit cost-for engineering He = engmeermg employee-hours fj = unit cost per drawing or specification d = number of drawings or specifications fp = construction or field expense factor always greater than 1... 

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