WRPS Pipe Stress Analysis ConsiderationsAll of the waste transfer pipelines were designed and analyzed in accordance with ASME B31.1 or B31.3. The following design requirements are typical for a transfer piping systems or jumper assembly;1. Per TFC-ENG-STD-22, Piping, Jumpers, and Valves, the piping and jumper assembly design pressure is typically specified as 400 psig at 200 F. The piping is categorized as ASME B31.3 normal fluid service per section 3.2.3 and/or 3.2.4.1 of TFC-ENG-STD-22.2. Per RPP-CALC-44685, Calculation Package for the AP Valve Pit Jumpers; Table 3, provides a delta analysis methodology between various editions of the ASME B31 series. 3. Per RPP-CALC-51260, High Pressure Flexible Metal Hose Design Pressure Analysis, Section 9.1.4, provides for the specification of the corrosion and erosion allowances on the schedule 40S stainless steel pipe. Typically this value is taken to be 0.0145 inches over the life of the pipe or jumper and the same allowance is specified for flexible metal hose. TFC-MD-085, Design Conditions for Analyses of Process Piping, specifies a corrosion/erosion rate of 0.0012 in/year.4. The specific gravity of the waste is specified at 1.6. Typically supernatant in the DST system is between 1.0 and 1.4. This value is therefore conservative.5. Per RPP-RPT-42297, Safety-Significant Waste Transfer Primary Piping Systems-Functions and Requirements Evaluation Document, Section 6.2 states that Cycle fatigue is not considered an issue because of the limited number of cycles imposed on the jumpers during the specified service life. Therefore, the piping or jumper will not be subjected to greater than 7,000 pressure and/or thermal cycles.6. The pipe/jumper is located underground or in a below grade pit and the process fluid temperature is above normally 32F. Per TFC-ENG-STD-02, Section 3.1.1, minimum metal temperature is taken to be -25F. Maximum metal temperature is the same as design temperature. (Note: minimum metal temperature is only used for flexibility analysis and has no relation to temperatures the process fluid will encounter.)7. TFC-MD-085 and ASME B31.3 requires that steady state and fluid transient flow analysis is required. The effects of postulated water hammer events shall be evaluated. The bounding value for the wave speed of the slurry is to be based in RPP-RPT-50042, Bulk Modulus and Sonic Velocity Estimates for Double-Shell Tank Supernatants, Table 4, including consideration for a higher temperature. The effects of water hammer shall be evaluated in the stress analysis calculation. The peak water hammer pressure shall be considered as an occasional load.8. TFC-MD-085, Section 1.0 requires that the capability of the safety-significant waste transfer piping to withstand the effects of potential waste transfer pump overpressure be evaluated.9. The pressure and stress limits for existing waste transfer piping and associated flush water piping are to be in accordance with RPP-RPT-52248, and TFC-ENG-FACSUP-C-27, respectively.A typical summary of design conditions, from ASME B31.3, for a transfer piping system or jumper assembly is listed as Table 51.

Table 51. Summary of Design Conditions per ASME B31.3

ASME B31.3 Section301 Design ConditionSummary of RequirementDescription of Application in Analysis

301.2 Design Pressure

301.2.1 GeneralThe design pressure of each component in a piping system shall be no less than the pressure at the most severe condition of coincident internal or external pressure and temperature (minimum or maximum) expected during service.Design pressure is typically 400 psig per TFC-ENG-STD-22. Piping design pressures for all DST waster transfer piping to be tabulated.

301.2.2 Required Pressure Containment or ReliefProvision shall be made to safely contain or relieve any pressure to which the piping may be subjected. Piping not protected by a pressure relieving device, or that can be isolated from a pressure relieving device, shall be designed for at least the highest pressure that can be developed.Design pressure is typically 400 psig per TFC-ENG-STD-22. Pressure relief devices shall be denoted on the system P&IDs, if any.

301.3 Design Temperature

301.3.1 MinimumDesign TemperatureThe design minimum temperature is the lowest component temperature expected in service. This temperature may establish special design requirements and material qualification requirements.Design minimum temperature is -25F degrees; per TFC-MD-085. Piping design temperatures for all DST waster transfer piping to be tabulated.

301.3.2 Un-InsulatedComponentsDescribes requirements for the piping at specific fluid temperatures.N/A. The pipe/jumper is designed to a maximum temperature of 200F. All components of the pipe/jumper are evaluated at this temperature.

301.3.3 ExternallyInsulated PipingThe component design temperature shall be the fluid temperature unless calculations, tests, or service experience based on measurements support the useof another temperature. Where piping is heated or cooled by tracing or jacketing, this effect shall be considered in establishing component design temperatures.Process fluid temperature is below 200F and is used without qualification. Components are not externally cooled, heated, or insulated.

301.3.4 InternallyInsulated PipingThe component design temperature shall be based on heat transfer calculations or tests.N/A. The pipe/jumper assembly is not internally insulated.

301.4 Ambient Effects

301.4.1 Cooling: Effects on PressureThe cooling of gas or vapor in a piping system may reduce the pressure sufficiently to create an internal vacuum. In such a case, the piping shall be capable of withstanding the external pressure at the lower temperature, or provision shall be made to break the vacuum.N/A. The pump and piping is free draining to the tank and therefore will not generate a vacuum.

301.4.2 FluidExpansion EffectsProvision shall be made in the design either to withstand or relieve increased pressure caused by the heating of static fluid in a piping component.N/A. Pipe/Jumper is free draining and does not have a means of isolating static fluid.

301.4.3 AtmosphericIcingWhere the design minimum temperature of a piping system is below 32F, the possibility of moisture condensation and buildup of ice shall be considered and provisions be made in the design to avoid resultant modifications.N/A. Fluid temperature is above 32F and will prevent atmospheric icing.

301.4.4 Low AmbientTemperatureConsideration shall be given to low ambient temperature conditions for displacement stress analysis.Low ambient temperature used in displacement stress analysis is -25F per TFC- MD-085.

301.5 Dynamic Effects

301.5.1 ImpactImpact forces caused by external or internal conditions (including changes in flow rate, hydraulic shock, liquid or solid slugging, flashing, and geysering) shall be taken into account in the design of piping.Pipe/Jumper is located underground or in covered concrete pit and therefore not designed for external impact forces.

301.5.2 WindThe effect of wind loading shall be taken into account in the design of exposed piping.N/A. Since piping/jumper is located underground or in covered pit (protected), wind loading will not be analyzed.

301.5.3 EarthquakePiping shall be designed with earthquake loading taken into account.Piping/jumper is analyzed using PC-2 seismic criteria per TFC-ENG-STD-06.

301.5.4 VibrationPiping shall be designed, arranged, and supported so as to eliminate excessive and harmful effects of vibration which may arise from impact, pressure pulsation, turbulent flow vortices, resonance in compressors, and wind.Wind and impact effects are N/A; pipe/jumper is located underground or in covered pit. A flexible connection to rotating equipment (pump) is provided to mitigate vibration.

301.5.5 DischargeReactionsPiping shall be designed, arranged, and supported so as to withstand reaction forces due to let-down or discharge of fluids.N/A. Piping/jumper does not include discharges.

301.6 Weight Effects

301.6.1 Live LoadsThese loads include the weight of the medium transported, or the medium used for test. Snow and ice loads due to both environmental and operating conditions shall be considered.Snow and ice loads are N/A; pipe/jumper is located underground or in covered pit. The specific gravities of the transfer fluid are specified per WRPS design criteria reports.

301.6.2 Dead LoadsThese loads consist of the weight of piping components, insulation, and other superimposed permanent loads supported by the piping.Weights analysis of the complete piping system is to be determined by separate calculations.

301.7 Thermal Expansion and Contraction Effects

301.7.1 Thermal Loads due to RestraintsThese loads consist of thrusts and moments which arise when free thermal expansion and contraction of the piping are prevented by restraints or anchors.Thermal expansion loads analysis of the complete piping system is to be determined by separate calculations.

301.7.2 Loads Due toTemperature GradientsThese loads arise from stresses in pipe walls resulting from large rapid temperature changes or from unequal temperature distribution as may result from a high heat flux through a comparatively thick pipe or stratified two phase flow causing bow of the line.N/A. Since the pipe/jumper is not subject to significant unequal temperature distribution, this loading is typically not analyzed.

301.7.3 Loads Due to Differences in Expansion CharacteristicsThese loads result from differences in thermal expansion where materials with different thermal expansion coefficients are combined, as in bimetallic, lined, jacketed, or metallic- nonmetallic piping.N/A. Since the pipe/jumper does not contain components that meet this criteria, this load is not analyzed.

301.8 Effects of Support, Anchor, and Terminal MovementsThe effects of movements of piping supports, anchors, and equipment shall be taken into account in the design of piping. These movements may result from the flexibility and/or thermal expansion of equipment, supports, or anchors; and from settlement, tidal movements, or wind sway.Only the effects of settlement are potentially applicable and shall be addressed in the analysis.

301.9 Reduced DuctilityEffectsThe harmful effects of reduced ductility shall be taken into account in the design of piping. The effects may, for example, result from welding, heat treatment, forming, bending, or low operating temperatures, including the chilling effect of sudden loss of pressure on highly volatile fluids. Low ambient temperatures expected during operation shall be considered.N/A. Since the pipe/jumper assembly does not contain components which are significantly affected by welding, low temperatures, etc., reduced ductility effects shall not be analyzed.

301.10 Cyclic EffectsFatigue due to pressure cycling, thermal cycling, and other cyclic loadings shall be considered in thedesign of piping.Per RPP-RPT-42297, the pipe / jumper will not be subjected to greater than 7,000 pressure and/or thermal cycles.

301.11 AirCondensation EffectsAt operating conditions below -312F in ambient air, condensation and oxygen enrichment occur. These shall be considered in selecting materials, including insulation, and adequate shielding and or disposal shall be provided.N/A. Since pipe/jumper is not subjected to operating conditions below -312F, air condensation effects shall not be analyzed.

302 Design Criteria

321 Piping Support

321.3.2 IntegralAttachmentsIntegral attachments include plugs, ears, shoes,plates, and angle clips, cast on or welded to the piping. Consideration shall be given to the localized stresses induced in the piping component by welding the integral attachment. (a) Integralreinforcement, complete encirclement reinforcement, or intermediate pads of suitable alloy and design may be used to reduce contamination or undesirable heat effects in alloy piping. (b) Intermediate pads, integral reinforcement, complete encirclement reinforcement, or other means of reinforcement may be used to distribute stresses.Any integrally welded attachment between the piping and dunnage shall include an appropriate stress intensification factor.

The load conditions analyzed per ASME B31.3 for a typical DST waste transfer piping are summarized below in Table 52.

Table 52. Waste Transfer Piping Stress Analysis Load Conditions per ASME B31.3

Load ConditionDescriptionCommentCode

Internal PressureAt design pressureHoop StressASME B31.3ASME Sec. III, ND-3641

Sustained Load (Sus)At design pressure. Includes deadweight of piping (weight of pipe, fluid, components, and insulation), and superimposed loads acting through pipe supportsLongitudinal StressASME B31.3ASME Sec. III, ND-3655

Sustained Load PlusThermal Plus Seismic(Support Loads)At design pressure and temperature.For supports, support weld, anchor, nozzle, PUREXconnector, and other reactions.ASME B31.3, 321.1

Occasional Seismic LoadPlus Sustained LoadAt design pressure. Includes one load case for each of the following combinations. + X (horizontal) + Y (horizontal) + Z (vertical) + X (horizontal) - Y (horizontal) + Z (vertical) - X (horizontal) + Y (horizontal) + Z (vertical) - X (horizontal) - Y (horizontal) + Z (vertical) + X (horizontal) + Y (horizontal) - Z (vertical) + X (horizontal) - Y (horizontal) - Z (vertical) - X (horizontal) + Y (horizontal) - Z (vertical) - X (horizontal) - Y (horizontal) - Z (vertical)Occasional load stressASME B31.3ASME Sec. III, ND-3655

Occasional HydraulicTransient Load PlusSustained LoadAt design pressure. Includes one load case for each of the following conditions. Pressure surge Pressure dropOccasional load stressASME B31.3ASME Sec. III, ND-3655

Occasional PSV Discharge Load Plus Sustained LoadAt design pressure. Includes one load case for each of the following conditions. Concentrated PSV discharge forcesNot Applicable for this analysis.ASME B31.3ASME Sec. III, ND-3655

Hydro test PressureAt hydrostatic test pressure (1.5 x design pressure)Not Applicable for this analysis.ASME B31.3

Thermal ExpansionAmbient temperature to maximum design temperature.Ambient temperature is 60 F.Displacement Stress RangeASME B31.3Only largest range isrequired by code, see 319.2.3

Max. RangeIf maximum range combination is selected.Non-Code Case

The pressure and stress limits for DST waste transfer piping or jumper assemblies, including supports and welds to supports are typically determined for ASME B31.3 piping as follows:Internal PressureInternal pressure in the piping and jumper assembly due to sustained or occasional loads shall be considered safe when it is less than the Design Pressure of piping and components, including any variation in pressure allowable under the terms of ASME B31.3, paragraph 302.2.4. Variations in pressure are allowable for internal pressures up to 20% over the pressure rating or the allowable stress for pressure design at the temperature, provided the limitations specified in ASME B31.3, paragraph 302.2.4 are met. Variations up to 33% are allowable if these limitations are met and owners approval is provided.Longitudinal Stresses Sustained LoadsLongitudinal stress SL in the piping or jumper assembly due to sustained loads shall not exceed the basic allowable stress at the maximum metal temperature condition (Sh) provided for in ASME B31.3, Table A-1, and related Code requirements and allowances, when computed according to ASME B31.3, eq. 23a. (see ASME B31.3 para. 302.3.5(c), Stresses Due to Sustained Loads, SL)Longitudinal Stresses Occasional LoadsLongitudinal stress SL in the piping or jumper assembly due to occasional loads such as seismic, or anticipated flow transient loads occurring during waste transfers shall not exceed 1.33 times the basic allowable stress at the maximum metal temperature condition provided for in ASME B31.3, Table A-1, when computed according to ASME B31.3, eq. 23a. (see ASME B31.3 para. 302.3.6, Limits of Calculated Stresses Due to Occasional Loads, for additional limitations)Pipe Supports and Support WeldsFor analyses of sustained and occasional loads, design criteria for the piping or jumper assembly supports shall be per AISC Steel Construction Manual, 13th edition.Thermal FlexibilityThe calculated displacement stress range, SE, for the pipe or jumper assembly, shall not exceed the allowable stress range, SA, determined per ASME B31.3, eq. 1a or 1b, independent of longitudinal stress. Hydrostatic TestFor determination of hydrostatic test pressure Equation 24 from ASME B31.3 Section 345.4.2 is used.