This update does not effect material, gasket, or other files that are typically customized by RCS users. Nonetheless, it is always a good idea to make a complete backup of your RCS installation by creating a copy of the entire RCSWin folder and all files in it. This ensures that you will be able to resort back to the previous version should any problems with the installation arise.
Note: To get a printout of all instructions, program and file updates, enhancements, and corrections from within RCS, go to Tools -> Administrative and double click on Edit / Print Updates.
(1) Summary of Changes in this Update: (a) The help system within RCS is completely overhauled. While there are still portions of RCS that use the older help, a large percentage of screens, programs, and utilities within RCS are all now using a single, comprehensive help system. This new help system is intended to replace the somewhat disjointed and non-integrated help that existed previously in a variety of different formats. See item ( 2) below for more info. (b) Changes were made to Part UHX of the Code. There were two main changes. The first is relatively simple: UHX has added a provision that allows for the use of a different temperature and subsequent allowable stress for the flanged extension portion of the tubesheet. The second change is the addition of a subsection that pertains only to fixed tubesheet kettle type exchangers. See ( 3) below for additional information. (c) A new utility has been added to run Appendix O calculations. More specifically, this is for API-660 / ASME PCC-1 Appendix O / WRC Bulletin 538 - Gasket Stress / Bolting Stress Analysis. This new utility is an optional calculation that can be performed on any body flange, and can be accessed from the main flange screen (Run -> Menus -> Flange, then select the desired flange, and click the "App O" button. See ( 4) below for additional information. (d) In the previous update, new bolting tables were added to accommodate the use of bolt tensioners, as the standard bolt tables do not allow for sufficient clearance. However, we inadvertently left out the ability to use these new tables when running floating head calculations. A similar change code (Code 94) has been added at the top of the list of change codes to allow the use of these new tables when making bolting selections. Note that this also allows for the use of other modified bolting tables (such as a table for metric bolts). (e) All applicable data from ASME Code charts and tables, such as heat treat data, radiograph data, x-ray data, impact test exemption data, external pressure charts, paragraph references for UHX, UCS, UHA, UNF, etc. have all been updated to the 2017 edition of ASME Code. (f) All of the materials' allowable stresses, yield stresses and physical properties in Section II part D of the 2017 ASME Code are available and included in this update. Instructions on how to update your current materials database to the new values are given below in ( 5). (g) Fixed a few random bugs, errors, and print formatting issues that users had encountered.
(2) New Comprehensive Help System for RCS (a) Firstly, the new help system is the first aspect of the RCS software to be compiled to the .NET framework. What this means is that the Microsoft .NET framework must be installed (specifically, version 3.5 or higher) on each machine that runs RCS. The .NET framework is NOT packaged with RCS, but is available as a free download from Microsoft. However, the .NET framework is included on all new Windows machines, and is updated in the same fashion as all other Microsoft updates, so in the vast majority of cases, there should not be any further requirements after running the RCS update. (b) The new help system is intended to replace a variety of other help options. The old help system that was loaded when you clicked Help -> Contents has all been built into the new help system. All of the sketches and help topics from that help system are now included in the new help menu. (c) Similarly, the "online help" option is no longer necessary. It is still available by clicking Help -> Online, but will eventually be removed entirely. The vast majority of the online help topics are all built into the new system, and once the migration is 100% complete, the online help will be removed. (d) Similarly, the RCS procedure notes that can be enabled and disabled from the RCS settings are really no longer necessary. The option to enable the procedure notes is still there, at least for the time being, but they will ultimately eventually be phased out, as the info contained in these notes is all contained in the new help system. (e) Lastly, the content from many of the Word help documents located in the \RCSWin\RCSOverview folder is now built into the new help system, and the remaining help documents will also be integrated in when the system is 100% complete. (f) From any screen within RCS, clicking F1 will bring up the overall help topic associated with that screen, and scroll you to the help item that is specific to the field that the cursor was on. Similarly, clicking F2 will load the overall help topic for the current screen. Note that all screens that have not yet been integrated into the new system will continue to function as before, bringing up the old help as in previous versions of RCS. (g) There is also a search option within the new help system. Click the magnifying glass icon and type in search words, and a list of all help topics related to the search words will be revealed.
( 3) Modifications required by changes in Part UHX There are two main changes that were made in the 2017 UHX section for tubesheet design: (a) The first is fairly simple. UHX-9.3 has added a new allowable stress for the extended portion of the tubesheet, whether flanged or not. This allows the extended portion of the tubesheet to be designed at a different (presumably lower) design temperature than the main central portion of the tubesheet. TEMA had a similar capability in years past. By default, RCS assumes that the temperature of the central portion of the tubesheet and the extension are the same. There are two types of tubesheet extensions: (1) Flanged extensions that have bolt loads applied to them as defined by UHX-9.5(a). This calculation is based solely on the bolting moments passed to it from the mating flanges. RCS actually already had this capability built in. The input allows for a different allowable stress to be used in this calculation. The calculation is done only once and is included as hr on the first page of the UHX printout. (2) Unflanged tubesheet extensions are addressed in UHX-9.5(c). The RCS variable that defines this calculation is hrDE. The Code states that this calculation should be done for each design loading case and consequently it is shown on each individual case printout. In the "Auto Set Cases" form, we have added a temperature field for the user to input the desired temperature at which the allowable stress is determined. The stress is determined for you, for each case accordingly. As with all allowable stresses, RCS allows for setting these values on a case by case basis, if so desired.
(b) The major change is the addition of section UHX-13.10, which applies only to fixed tubesheet kettle type exchangers. The new method uses the same basic methodology of the standard UHX-13 section which applies to fixed tubesheet exchangers. However, UHX-13.10 contains new variables that are used "in place of" existing variables for steps 2, 5, 6, and 10. These new variables help reflect the additional pressure head associated with the larger kettle section of the exchanger. Section UHX-13.10.2 contains the "Conditions of Applicability" for utilizing this new method. Basically both cones must be identical and there must be identical stub cylinders at each end to attach the cones to the tubesheets. There are also restrictions with regard to the relative length of the cone, and to the ratio of the large end and small end of the cones. RCS will warn you if you do not meet one of these criteria. UHX-13.10.4(d) requires calculation of axial membrane stresses for the small stub cylinder, the kettle cylinder, the small end of the cone and the large end of the cone. Each of these must be within defined limits. Again, RCS will do it's best to accommodate all these, but at some point the program will quit trying and simply warn you that all cases did not pass, just as before. Generally a solution can be obtained by thickening one of the cylinders, the cone, or perhaps changing the cone geometry. The easiest way to determine which component is failing is to view the stress summary at the end of the UHX printout.
In general it appears that this new method often results in a tubesheet that is slightly thicker than the previous method, since it is accounting for the larger kettle diameter which is subject to pressure.
( 4) Appendix O Calculations (a) A method to calculate the Gasket Stress / Bolting Stress analysis in API-660 7.8.1 is now included in the RCS software. API-660 states that it is not “mandatory”, but is to be used “when specified by the purchaser”. None-the-less, we have gotten an increasing number of inquiries with regard to this calculation, so it is now included in the software. The calculation method utilizes the ASME PCC-1 Appendix O method, which is referenced in API-660 as the “joint component approach” and is recommended. The Appendix O paper references WRC Bulletin 538 as a method to determine the maximum bolt stress that will not damage the flange. The method can be accessed via the flange screen. In short, the calculations arrive at two maximum allowable bolt stresses and two minimum bolt stresses. The two maximum bolt stresses are the stress in the bolts that would overstress the flange (determined by WRC-538), and the bolt stress, above which, you would “crush” the gasket. The two minimum bolt stresses are the bolt stress required to seat the gasket at test conditions as well as the bolt stress required to maintain a seal on the gasket during operation. Ideally the calculations will yield a range of bolt stresses that can be utilized that falls between the smaller of the two maximums and the larger of the two minimums. This is not always the case. There is a lengthy explanation of this whole procedure that is available in RCS on the flange menu. (b) Sometimes a “range” can be obtained by thickening up the flange, if that is the limiting component. Sometimes adding bolting helps so that less stress has to be applied, per bolt, to seat or keep seated, the gasket. Consideration may be given to increasing the gasket width if the gasket is controlling. Sometimes it is impossible to achieve a range and the paper suggests that consideration be given to all aspects and good engineering judgement used to determine the proper bolting stress to be used.
( 5) Updating your materials database to the 2017 values. (a) Before reading the entire material update explanation, it is worth noting that the RCS material update program is sent out with the most likely defaults already selected. If you are unsure what the best course of action is, after reading the information below, your best bet is most likely to just use the defaults that are already selected in the program and run through the steps to update your database described below without worrying about making changes to the options and settings. It is also worth noting that far more extensive help is available within the software under the Materials heading of the new help system. (b) If you are unsure what material database you are currently using, the answer is located in the bottom right hand corner of the main RCS window. 13 indicates the 2013 edition, 15 indicates the 2015 edition (which was the most recent one available prior to this update), and 17 indicates the latest edition (2017). While older versions than these are available within RCS, it is unlikely that anyone is still using these older versions on a regular basis. (c) Click "Tools"->"Setup"->"Material Update" from the main RCS screen. This opens the RCS material update program. The first field is the "source" material file, and this should be set to your current material database (15 for most people). The second field is the "destination" material database, and should always be set to 17, since the goal is to create a version of your material database that uses values out of the 2017 ASME Section II Part D tables. (d) Search Settings: In almost all scenarios, you want to leave the first option set to "Yes", and all others set to "No". This will search based on a unique material ID, which is the safest way to locate each material from one version of ASME to the next. (e) Save Settings: The default is to clear out any data that is not found in the destination material files. What this means is that if you have added any materials to your material database that RCS can not successfully locate in the 2017 edition of the tables, RCS will remove this material entirely from the new version of your database. This is the absolute safest way to ensure that all material data you use will be from the latest edition of ASME, but it is also the way that is most likely to result in lost materials. However, after testing on the standard RCS material database, we can confirm that ALL materials are successfully brought over to the 2017 tables, so hopefully other people will see similar results with their unique material databases. (f) When you are satisfied with the settings, click the "OK/Build" button. This will pop up a window that is a summary of all materails in your database, and you can even edit on a material by material basis, any of the settings that were shown on the previous screen in this text file and save the changes. Most users will just glance through this file without changing anything. Close the file, and RCS will then begin the process of updating each material in the database sequentially. This process can take a few minutes to complete. (g) When the process is complete, a final summary of the results will be displayed. The summary shows a listing of all materials from the previous database, and a warning will appear next to any material that was not brought over. Note that several materials may have a note that reads "No yield in source". ASME has a number of materials that do not have values in their yield stress table. However, almost all of these materials are bolting, and yield values are not required for bolting calculations anyway. This note would only be a cause for concern if the material in question needed yield stress values for ASME calculations. (h) The final (and most important) step is to actually change to using this material database! Running the update creates the 2017 material database, but it does not automatically switch you to immediately start using it. Click "Tools"->"Setup"->"Materials" from the main RCS menu to run the material editor. This utility lets the user add new materials, or switch between the different material databases. The top line reads "Current RCS Material File", and you will need to select the 17 option, which was not in the list until after the above steps were executed. After doing this, you will be using the 2017 ASME material properties for all jobs so long as you do not ever change back to a different database from this same screen. (i) Lastly, if anyone has questions or problems with their material update, feel free to contact RCS via phone or email using the contact info shown at the top of this help summary.