Applies To Product(s): AutoPIPE, Version(s): 2004, XM, & V8i Environment: N/A Area: Modeling Subarea: Original Author: Bentley Technical Support Group Attention: Please see the following AutoPIPE help section: Help > Contents> Contents Tab> Modeling Approaches> Modeling Approaches> This help has been provided in order to give users ideas for modeling typical piping arrangements. The steps shown in each example should not be taken as the only method available to create models. In addition, the intent of the examples is to present ways to create adequate models of specific piping components for analytical purposes. Anchors Bends Cuts Flexible Joints Frames Hangers Nozzles Pipes Reducers Rotating Equipment Supports Tees Valves Vessels Questions, and Answers: Item #1. How to model typical flanges in AutoPIPE V8i 9.6 and Lower: Answer: In AutoPIPE V8i 9.6 and lower, flanges are a 1 point element with no length> The program only considers the flange weight and weld connection for SIF calculations. Assuming flange stiffness is same as the pipe is technically incorrect because a flange is more rigid than pipe. However, it does NOT affect analysis results to any significant extent. You can choose to model a flange as a single point or take into consideration the actual flange length. See the following procedure to model the actual flange length: A. Assuming a flanged nozzle connection to be anchored to a vessel, insert an anchor. B. Insert a short run of pipe equal to the actual flange length. C. Insert another pipe run and to the next node point in the model. D. Insert a flange at Nozzle interface, in this example, start of the segment/anchor point. On the flange dialog, change Joint End Type = " User Defined", set "Joint SIF" = 1.0 (note: can use any joint end type connection so long as the SIF calculated is 1.0 at the flange point) E. Select this short length of pipe representing the actual flange length, press Insert > Rigid options over Range (Include Weight = off, Include Thermal Expansion = off...pipe will be shown purple), and press OK button. Note: With regards to Rigid properties, It is more of a design decision by the individual person if there would be expansion of the flange in the axial direction, then the Rigid Properties > Thermal Expansion should be turned ON. F. Select the node point representing the flange connection to the pipe. Press Insert > Xtra Data> Joint Type user SIF. Select the correct type of end connection or enter a user SIF. (From AutoPIPE V8i 9.5) Item #2. Model a Anchor flanges: Answer: Anchor flanges are considered to be buried within concrete. Modeling approach: A. On the segment where the flange is to be modeled, insert a node point (ex. B04) as the welded connection between he pipe and flange B. Insert a Pipe run half the total length of the Hanger flange (ex. B05). C. Insert another Pipe run with the same length as in Step B above (ex. B06). D. Select the middle point of the flange (ex. B05), insert a flange component. On the flange dialog, change Joint End Type = "User Defined", set "Joint SIF" = 1.0 (note: can use any joint end type connection so long as the SIF calculated is 1.0 at the flange point) E. Select both pipe runs (ex. B04-B05 & B05-B06), press Insert > Rigid options over Range (Include Weight = off, Include Thermal Expansion = off...pipe will be shown purple), and press OK button F. Select both flange end points (ex. B04 & B06), Press Insert > Xtra Data> Joint Type user SIF. Select the correct type of end connection or enter a user SIF. G. Connection to support: choose one of the following, model connection as simple supports or model with soil properties Notes: i. Model connection as simple support: add additional node points (ex. B03 & B07) with rigid pipe properties as done is step E to represent pipe entombed in concrete. At the locations where the pipe enters the concrete add AutoPIPE supports or anchors as needed. ii. Model connection with soil properties: add additional node points to represent pipe entombed in concrete. Insert Soil properties over same node points added. Select all the pipe with in the concrete and apply the correct soil properties to mimic concrete. Item #3. Model a Hanger flanges: Answer: Hanger flanges are considered to be bolted to a structure. Modeling approach: A. On the segment where the flange is to be modeled, insert a node point (ex. B04) as the welded connection between he pipe and flange B. Insert a Pipe run half the total length of the Hanger flange (ex. B05). C. Insert another Pipe run with the same length as in Step B above (ex. B06). D. Select the middle point of the flange (ex. B05), insert a flange component. On the flange dialog, change Joint End Type = "User Defined", set "Joint SIF" = 1.0 (note: can use any joint end type connection so long as the SIF calculated is 1.0 at the flange point) E. Select both pipe runs (ex. B04-B05 & B05-B06), press Insert > Rigid options over Range (Include Weight = off, Include Thermal Expansion = off...pipe will be shown purple), and press OK button F. Select both flange end points (ex. B04 & B06), Press Insert > Xtra Data> Joint Type user SIF. Select the correct type of end connection or enter a user SIF. G. Connection to support: choose one of the following, model connection as simple supports or model with beam elements Note: i. Model connection as simple support: Insert AutoPIPE supports as need at the flange center point (ex. B05). ii. Model connection with beams: Insert rigid beam elements from the flange center (ex. B05) to the actual bolted support connection (ex Sq beam). Add additional beams with the correct beam properties from the bolted support connection to the support structure that is correctly supported (ex. Angle beams). Item #4, How to model a Stub End, Swivel, or Misalignment Flange Answer: The swivel flange is used with medium service pressures at points where the bolt holes in the mounting flanges are not precisely aligned. The swivel flange simplifies fitting between 2 fixed points. Answer: For strss analysis purpose, the program needs to know the weight and SIF associated with a flange. Most ASME piping codes do not have established SIF values for these types of flanges. Whilst ASME 16.5 and 16.47 codes are applicable for weld neck flanges, they are not applicable to swivel ring flanges beyond the bolt pattern and bolt sizes. ASME offer alternative rules that consider swivel ring flanges as non-standard, or loose type, flanges. Therefore the modeling appraoch for these types of flanges: Select the node point where the flange is to be located, press Insert> Flange>, on the flange dialog screen enter: Flange type = NS Pressure Rating = NS Weight = enter weight from vendor literature Joint End Type: User Defined Joint SIF: contact flange manufature for value to be used. Note: One could argue to set Joint end type = "Lap joint" in order to automatically calcuale the SIF. However, since these types of joints are not covered by the applicable piping code, you will need to use engineering judgement or contact the manfacture. Bentley TSG cannot provide a definative value. See Also Bentley AutoPIPE External Links Bentley Technical Support KnowledgeBase Bentley LEARN Server Comments or Corrections? 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