ASME B31E pdf download

ASME B31E pdf download.Standard for the Seismic Design and Retrofit of Above-Ground Piping Systems.
ASME B31E establishes a method for the seismic design of above-ground piping systems in the scope of the ASME B31 Code for Pressure Piping.
1.1 Scope
This Standard applies to above-ground, metallic piping systems in the scope of the ASME 1131 Code for Pressure Piping (831.1, B31.3, 831.4, 831.5, 831.8, 831.9. B31.11). The requirements described in this Standard are valid when the piping system complies with the materials, design, fabrication, examination, testing, and inspection requirements of the applicable ASME 831 Code section.
1.2 Terms and Definitions
active components: components that must perform an active function, involving moving parts or controls during or following the earthquake (e.g., valves, valve actuators, pumps, compressors, and fans that must operate during or following the design earthquake).
axial seismic restmint: seismic restraint that acts along the pipe axis.
critical piping: piping system that must remain leak tight or operable (see definitions) during or following the earthquake.
design earth quake: the level of earthquake for which the piping system is to be designed for to perform a seismic function (position retention, leak tightness, or operability).
ductile piping si,stem: in the context of this Standard for seismic qualification, ductile piping system refers to a piping system where the piping, fitting, and components are made of material with a minimum elongation at rupture of 15% at the temperature concurrent with the seismic load.
frre-fkld seis,nic input: the ground seismic input at the facility location.
in-structure seismic input: the seismic excitation within a building or structure, at the elevation of the piping system attachments to the building or structure.
lateral seismic restraints: seismic restraints that act in a direction perpendicular to the pipe axis.
3.7.2 The seismic adequacy of seismic restraints shall be determined on the basis of vendor catalogs, and the applicable design method and standard, such as MSS SP-58 or MSS SP-69 for standard support components, AISC or AISI for steel members, and AC! for concrete anchor bolts. The qualification of seismic restraints shall also address the prevention of buckling.
3.7.3 The seismic adequacy of nonseismic restraints shall also be verified if they are expected to perform a function after the earthquake. For example, spring hangers should not be permitted to pull off the wall if they are necessary to support the pipe weight after the earthquake.
3.7.4 For lateral seismic restraints, a total diametric gap equal to in. (12 mm) is acceptable. A gap up to OlD or 2 in. (50 mm), whichever is smaller, is permitted, provided the seismic load, calculated on the basis of zero gap. is multiplied by an impact factor of 2. Larger gaps or smaller impact factors may he justified by analysis or test.
3.7.5 Short rod hangers Itypically less than 12 in. (300 mm) longj may provide a restoring force that tends to limit side-sway of hung pipe, and may he considered as seismic restraints, provided they arc designed to sustain the seismic loads and movements.
3.8 EquIpment and Components
The seismic and concurrent loads applied by the pipe at equipment and component nozzles shall be qualified as part of the seismic design or retrofit of the piping system, to a degree commensurate with the required system function, as specified in para. 1.3.
For position retention, it is usually sufficient to show that the piping loads on equipment and components will not cause rupture. For leak tightness. the stress shall be maintained within yield or shown not to cause fatigue ruptures. For operability, the piping loads shall be kept within operability limits established by detailed analysis, testing, or similarity to seismically qualified equipment or components.
Components with unsupported extended structures, such as valves with heavy motor operators, shall be evaluated to insure that the extended structure does not fail during a seismic event, For components with unsupported extended structures, a natural frequency check shall be performed and shall be greater than 33 cps. When the natural frequency is less than 33 Hz, the component extended structure shall be stiffened as recommended by the component manufacturer.