Read the following information in conjunction with the tasks required for Extract and organize data from PDS, which describes how to extract and pre-process the PDS data to use I-Convert.
Piping Master Class (PMC) file
PDS uses a file known as the Piping Master Class file (usually with the extension *.pmc), which includes a list of all the specifications to be used on a project. Each specification has a one line entry, containing references to other data, which is common to all components in that specification. The following sample .pmc file describes the structure and content of this file in more detail.
Piping Commodity Specification Data (PCSD) file
A PDS specification is presented as an ASCII file containing a list of the permitted components and their nominal sizes. The file is known in PDS as the Piping Commodity Specification Data file. The file name consists of the name referred to in the entry in the .pmc file with the extension .pcd. This specification is commonly referred to as the .pcd file.
Each entry in the. pcd file refers to a single component with a specific continuous range of nominal sizes. If discontinuous size ranges are required, separate entries are included for each continuous part of the overall range. The entry also includes a number of parameters that are used in locating associated data, such as component description, dimensions and Isogen SKEY. A sample .pcd file is delivered with the software.
Commodity codes and item codes
Each entry in the .pcd file includes a commodity code. This code can either be the item code, which will eventually appear on an isometric drawing generated from within PDS, or it can be used together with the values of the primary and secondary bore as a pointer to an entry in an intermediate file known as the size dependent data file. In this way, unique item codes can be specified for each size of component without having to enter each size separately in the.pcd file. The following is an extract from a size dependent data file where the entries in columns 1 to 3 would be read from the. pcd file, and the corresponding unique item code would be read from column 4.
! SIZE DEPENDENT DATA
! Wed Jun 24 19:03:7 Intergraph Corporation.1998
! 2=sys_commodity_code
! 3=gcp_nom_diam
! 4=rcp_nom_diam
! 5=gcp_sch_thk
! 6=rcp_sch_thk
! 7=commodity_code
! 8=weld_weight
! 9=unit_price
! 10=manhours
Single_Spacing
Sequence= 2 3 4 5 6 7 8 9 10
! 2 3 4 5 6 7 8 9 10
1011_883 25mm 25mm NREQD NREQD G18591 - - -
1011_883 40mm 40mm NREQD NREQD G18592 - - -
1011_883 50mm 50mm NREQD NREQD 1472855 - - -
1011_883 65mm 65mm NREQD NREQD G18593 - - -
1011_883 80mm 80mm NREQD NREQD 1472856 - - -
1011_883 100mm 100mm NREQD NREQD G18595 - - -
Component descriptions
After the component item code is determined, it is used as the pointer to the associated description in the Short descriptions file. The description can be either a simple text string enclosed in single quotes, which can be used directly, or it can have embedded codes which need to be decoded to create the description required for the Smart Isometrics catalog.
There are two types of embedded codes. Any text enclosed in | marks (or between a | and the end of the string) is a comment which should be removed from the description. Any number enclosed in [ ] is a pointer to a PDS label which is defined in the Label Definition file (typically Label.rpt).
The following example illustrates how complex descriptions are decoded. The commodity code, such as FAAAAAWAAA, is read from the .pcd file and used as the pointer to find the corresponding record in the Short description file:
FAAAAAWAAA 'Flange, CL150, FFFE/BE, ASTM-A105, ANSI-B16.5, WN, [409]|bore to match|'
The item code, the single quotes and the comment |bore to match|, is stripped from the description leaving:
Flange, CL150, FFFE/BE, ASTM-A105, ANSI-B16.5, WN, [409]
The definition of Label 409 is read from the Label Definition file as:
************** Label Type = 409 ****************
Label Name = Comp sch/thk 2 b
[1] bore
Piping component data
[1] cp_2_sch_thk - Character (8)
- ' bore'
*************************************
This is decoded as the schedule or wall thickness of the outlet end of the fitting (the weld neck) plus the sub string bore. Thus, if the weld neck flange has a schedule S-7 Intergraph Corporation.connection the complete description is as follows
Flange, CL150, FFFE/BE, ASTM-A105, ANSI-B16.5, WN, S-7 Intergraph Corporation.bore
Isogen SKEYs
A key field in the .pcd file is the PDS model code. This code is used to map to the required Isogen SKEY in the PDS ISOMAP.TBL file. In order to appear on the isometrics drawing, each model code associated with a component in the .pcd file must have an entry in the ISOMAP.TBL file. The entry defines the Isogen SKEY to be used and the Isogen IDF record type. The latter is required to differentiate between SKEYs where there is scope for confusion, for example, olet type fittings which can be either olets or couplings.
PDS Eden Code
Eden Code is a computer language like BASIC, which is used in PDS to define graphics and data sources for modeling. There are three classes of PDS data which are relevant to the creation of Smart Isometrics catalogs. The first is the Symbol Processor file, whose name consists of the prefix SP and the model code. A weld neck flange with the model code FWN is referenced as SPFWN in the Symbol Processor file.
This file includes a reference to a physical data source in the form:
physical_data_source = 'F1A' // Standard_Type
This reference can be decoded to form a file name as follows:
-
The file name starts with the prefix PD.
-
Anything inside single quotes is added as literal text.
-
A pair of backslashes (//) is converted to an underbar (_).
-
Standard_Type is converted to AMS, DIN, and so forth according to the standard which is applicable.
For an ANSI standard, the previous example converts to the file name PDF1A_AMS and for a DIN standard it converts to PDF1A_DIN.
This file contains two pieces of information relevant to the creation of Smart Isometrics catalogs. First, it defines a further physical data source, which is one of the generic files where the code defining the name of the file is where the dimensions are held. Second, it defines the relationship between the columns of data in the dimension file with the dimensions required in the Smart Isometrics catalog.
The following is the relevant extract from a sample file:
Physical_Data_Definition 'F1A_DIN'
physical_data_source = 'FLANGE_DIN'
Call Get_Physical_Data ( physical_data_source )
Call Read_Table ( Table_Name_A, input, output )
Surface_Area = Output_1
Wet_Weight = Output_2
Flange_Length = Output_3
Flange_Length = Flange_Length - Seat_Depth_1
Thickness_2 = Flange_Length - Thickness_1
If ( Flange_Length .eq. 0.0 ) Then
F_to_F_Dim = CP_Offset_1
Else
F_to_F_Dim = Flange_Length
Endif
This tells us that the generic physical data source file is called PDFLANGE_DIN and that the overall length of the weld neck flange (F_to_F_Dim) is found in the third output column of the file referenced by the variable Table_Name_A.
We can ignore the Seat_Depth_1 value for our purposes.
Smart Isometrics reads the PDF1A_DIN file to find the name of the physical data source file, and the other information specifies where the required dimensions are in the dimension file when we find it.
The following is an extract from the generic physical data source file PDFLANGE_DIN defining the name of the file where the dimensional data can be found:
Table_Name_A = Item_Name // Geo_Ind_Std // Gen_Flag_Green // Weight_Code
The file name can be decoded as follows:
-
The file starts with the prefix TD
-
Anything in single quotes is added as a literal text string
-
All the other items are variables defined in the *.pcd file.
The following is the weld neck flange record from the sample *.pcd file:
6Q2C01 1 15mm 1200mm 21 10 NREQD 105 - - 301 10 - 125 FV31CD1NCA 200. FWN 7124 - 4204 111 4 232 27 Intergraph Corporation.-
The file name is TDFWN_7124_105_111.
The file name definitions can be much more complicated than this including conditional definitions depending on comparisons of the two end types and values of certain data items specified in the .pcd file. For example, for the same flange under an AMS standard the definition is:
Table_Name_A = Item_Name // Geo_Ind_Std // Term_Type_1
Table_Name_W = Table_Name_A
Input_1 = Nom_Pipe_D_1
Input_2 = Nom_Pipe_D_2
If ( Gen_Type_2 .EQ. MALE ) Then
! Bolted X Male
Table_Name_A = Table_Name_A // Pr_Rating_1 // Term_Type_2 // 'A'
Table_Name_W = Table_Name_W // Pr_Rating_1 // Term_Type_2
If ( Pr_Rating_2 .EQ. NULL_PRESSURE ) Then
Table_Name_W = Table_Name_W // Sch_Thick_2
Else
Table_Name_W = Table_Name_W // Pr_Rating_2
EndIf
Table_Name_W = Table_Name_W // Weight_Code
Else
! Bolted X Female
Table_Name_A = Table_Name_A // Pr_Rating_1 // Term_Type_2 // Pr_Rating_2 // 'A'
Table_Name_W = Table_Name_W // Pr_Rating_1 // Term_Type_2 // Pr_Rating_2 // Sch_Thick_2 // Weight_Code
EndIf
In this case the file name construction is different depending on whether we have a flange with a Male (weld neck) or Female (Socket Weld or Screwed) end.
I-Convert reads this code and evaluates it according to the values in the* .pcd record for the item.
Component Dimensions
Having found the name of the file containing the dimensions, such as TDFWN_7124_105_111, the software can read it to find the information that it needs. Each physical data file contains dimensional information for a particular component over a range of bores. Therefore, once the correct file has been identified and the location of the data in the file has been determined, it is possible to look up dimensions for any bore in the range.
To do this it is necessary to specify which columns the data is in. In PDS this is done in the two physical data source files and in principle I-Convert can read this information and determine the appropriate mapping at run time. This is very complex, however, and relies in some cases on global variables evaluated in other files. To simplify the program, I-Convert has been developed to work with a user- defined mapping file which defines the relationship between the PDS data and the dimensions required for the Smart Isometrics catalog. This file is called xxMapEquation.txt. A sample file is supplied with I-Convert for both Appendix: Configuration Files.