The Pipe Loadings Transfer Program transfers an output data from piping stress analysis results to an input data of a structural analysis program. One of the purposes of the piping stress analysis is to provide pipe loadings for the structural analysis. These pipe loadings are composed of vertical loads and horizontal loads which are generated from weight, thermal and occasional loads of a piping stress analysis. In general, the piping stress analysis program will generate a large amount of data for a piping system such as deformations, stresses, forces and moments in each piping element, as well as the restraint reactions to equipment nozzles and the pipe support structure. The restraint reactions listed in an output file of the stress analysis results are the useful information to the structural analysis. This program is developed to give a systematic data transformation from piping stress analysis results to a pipe loading input file of a structural analysis program. The program flow chart is shown in Figure 1.
In general, the restraint reactions of piping stress analysis results are transferred to civil and structural department by means of marked up isometric drawings and restraint reaction tables from the stress analysis computer printout. The support nodes generated from the stress analysis program are marked-up on isometric drawings and the loadings of support nodes are printed-out in a restraint reactions table. Sometimes, the stress engineer also marks-up the maximum loadings on isometric drawings.
In every project execution, there will be some kind of procedures to be developed in order to transfer the pipe loadings from the piping department to the civil and structural department. These procedures are developed for the quality assurance and quality control during a project execution.
Because a large amount of data to be marked-up on isometric drawings and to be retrieved by structural engineers, troubles often appear during the transfer process.
The problems in the existing pipe loadings transfer system are caused by dealing with a large amount of data through several engineering discipline personal in a project. For example, piping stress engineers carry out stress analyses based on the pipe supports located by piping designers and the stress engineers may not have any idea about the structural layout. On the other hand, structural engineers after receiving the stress marked-up isometric drawings are often struggling to find out where are the pipe support locations in the piping structure. They may spend a lot of time to go through pages of marked up isometric drawings and the related restraint reaction tables to look for the piping forces for each pipe support. Furthermore, these piping forces at pipe supports have to be re-input manually to the structural analysis program. This tedious work has to be repeated again and again for every pipe support in the structural system.
The Pipe Loadings Transfer Program is developed to eliminate this tedious work and to streamline the data flow in order to save engineering time and reduce errors during the data transfer process. Many features such as easy to search, verify and edit data will provide the maximum flexibility to improve the data transfer process and to achieve a better structural analysis.
The Pipe Loadings Transfer Program is created for the improvement of data transfer by introducing a pipe support number at the pipe support in a plant design model. A pipe support number represented by three-dimensional coordinates in a plant space is introduced to identify the pipe support location in a plant design. A piping designer will locate the pipe support with a pipe support number (called a tag number) in a plant design. This tag number can be picked up by the plant design software in a file export menu of a PXF  file or a PCF  file. When the stress analysis program interfaced with a plant model using a PXF file or a PCF file, it will treat this tag number location as a pipe support location. Then the analysis results of a stress analysis program will show the restraint node number with a tag number at the support location in a restraint reactions table as shown in Figure 1.
For a piping stress analysis, the analytical results are presented in an output file with an out extension. The restraint reactions table in an output file will contain node numbers, tag numbers, and forces of pipe supports. All these information will form a unique database system for a pipe support and the data contained in this system unit can be manipulated in later analysis.
In the Pipe Loadings Transfer Program, each database unit can be edited, or searched based on pipe support numbers, restraint types or beam numbers respectively. In a physical sense, every pipe support is attached to a piping structure, and each beam on a pipe rack or on a piping structure may contain a number of pipe supports. This Pipe Loadings Transfer Program has a unique feature to link pipe support numbers to a beam number, as a result, this program has the ability to group all pipe support loadings, which are belong to a beam to form the beam loadings of a structure.
The Pipe Loadings Transfer Program inputs the restraint reactions output files in one at a time or in a group of many files. Each restraint reactions output file with an out extension contains node numbers, pipe support tag numbers, and forces of the restraints. If some information is missing, the missing information can be added or corrected, and then the modified information will be saved in the file.
A pipe support number (called a tag number) is placed at the pipe support location on a piping model by a piping designer. In a piping model, this tag number is inserted to the point on the centerline of a pipe at the support location and the coordinates of this point are used to designate as the tag number of a pipe support. This tag number contains eighteen digit numbers which are separated into three groups by hyphens. The first group of six digits represents the last six digits in a desired unit in the east or west coordinates of a plant. The second group of six digits represents the last six digits in the north or south coordinates of a plant. The third group of six digits represents the last six digits of a plant elevation. These numbers are the last six digits in a desired unit of a pipe support point in the X, Y and Z coordinate system of a plant.
These pipe support numbers can be presented on the isometric drawings. For easy viewing purpose, the six digits coordinates will be changed to three digits coordinates to show on isometric drawings. The tag number is a convenient pipe support designation for piping designers, stress engineers, structural engineers, construction and plant operation and maintenance personal to follow the same symbol.
The start point coordinates with a beam direction are introduced to identify as a beam member of a pipe frame structure. The start point coordinates of a beam number have an eighteen digit numbers format similar to the pipe support number.
In a 3D structural model, a structural member is defined from its start point coordinates to its end point coordinates. It will be convenient to follow a rule to include a positive increment to identify the length of a structural member. To apply this rule in consistent with the plant design software is to define the coordinates of a member in a direction from the west to east coordinate, or from the south to north coordinate to cover the span of a beam or from a low elevation to a high elevation to cover the height of a column. By doing this way, the coordinates of a structural member will have a positive increments from its start point to its end point.
In preparing a structural analysis, one of the tasks is to find out what are the piping loads acting on the beam of a pipe frame structure. Because the format of a beam number is similar to the format of a pipe support number, once a individual beam is chosen, then the elevation and the direction of the beam is determined, therefore those pipe support numbers with the same elevation and the same directional coordinate along the beam can be linked together as a group to form the pipe supports on a beam and the loadings of these pipe supports become the beam loadings. There are two icons to cover this type of operations: the Batch Run icon is for collecting the beam loadings and the Stringer icon is for collecting stringer loadings. The beam length tolerance for the Stringer will be less than 0.1 m to obtain good results.
The Pipe Loadings Transfer Program will link those pipe support numbers in a group for a beam number in the procedures as follows:
These operations shall group all the pipe support numbers to the related beam numbers together to form the beam loadings for a structure.
In a structural analysis, some questions are often to come up if all pipe loadings acting on a beam were completed, correct, or required any updated information to fulfill the structural analysis requirements.
The Pipe Loadings Transfer Program has the facility to search the information based on beam loadings, pipe support loadings, or horizontal loadings such as guide loads and anchor loads on a structure as shown in Figure 3.
When the Links window is opened, the following procedures shall be carried out to obtain loadings information on a beam:
When the Links window is opened, the following procedures shall be carried out to obtain the information on a pipe support number:
It is useful for a structural analysis to obtain the horizontal piping forces acting on a pipe support structure. This task can be accomplished by searching the restraint types of pipe supports on the search window as shown in Figure 3. These restraint types include guides, line stops and V-stops as defined by the stress analysis program.
The loading acting on a beam is called as point loadings. The location of a loading point on a beam is determined by the ratio of a support distance dividing by the full span length of a beam. This ratio can be obtained by invoking the structural Analyze button when the Beam Details window is opened as shown in Figure 6, and the detail procedures from inputting data files to creating structural models are presented in Figure 6A, Figure 6B, Figure 6C and Figure 6D respectively. For accuracy purpose of the structural analysis, six digits are employed in this window for all calculations.
This is the most efficient method to transfer the pipe loadings from stress analysis results to a structural analysis program.
The loadings acting at the joints of pipe support nodes are called as joint loadings. In order to obtain a better picture of the joints distribution in conjunction with the marked-up isometric drawings, it would be a good idea to input only one stress out file each time. The joint loadings shall be used for a pipe which is located outside of a pipe rack or for base supports which are located on the ground.
The beam numbers and the member numbers of a structure can be automatically generated by the beam number generator.
When the beam number generator window is opened as shown in Figure 8, the following procedures shall be carried out to generate beam numbers and their related member numbers:
When the structural model window is opened as shown in Figure 9, the following procedures shall be carried out to generate a structure model:
After the DXF file for the structural file being imported to the structural program, the joint loadings can be transferred to the structural program as shown in Figure 10 and the point loadings can be transferred to the structural program as shown in Figure 11 for the Risa-3D example and Figure 12 for the S-Frame example.
The pipe loadings transfer program develops a unique database to transfer pipe support loadings from stress analysis results to the pipe loading input file of a structural analysis program.
This is the data file transfer method to map the design data from one program to another program; as a result, the data transfer errors will be reduced.
A series of projects have employed the Pipe Loadings Transfer Program and proved that this program is reliable and applies the most advance technology in a plant design. The advantage of using the Pipe Loadings Transfer Program is simple, fast and accurate.
The pipe support number called tag number represents the support point coordinates on
After the pipe loading being transferred to the structural analysis model, each loading point shall show the same coordinates as the tag numbers. Therefore the tag number shall be used for loading editing if the stress analysis results had been revised.
A start point coordinates of a beam with a beam direction is introduced to identify a beam member. Some time, the user might wants to modify the beam coordinate with the revised value to the beam coordinate to obtain the correct results in the beam loading Analyzer window.
The Pipe Loadings Transfer Program provides 100 % accuracy on magnitude of loadings.
The advantages of using Pipe Loadings Transfer Program are accuracy and speed to
There are three types of Excel data files: beam loadings, structural grid loadings and GA loadings.
In order to obtain the pipe support loadings on beams and stringers of a structure model, two loading models shall be built on separated Risa-3D models, and then the append and merge features shall be used to combined them together to form a pipe loading model for a structural frame. To avoid any confusion on model append and model merge, the order of basic load cases shall be the same for beam loading model and stringer loading model. There will be a lot simpler if the redundant members in the beam and stringer model were deleted first before the operation of append and merge as follows: