---------------------------------------------------------------- May 9, 2008 FORGAS/FOROIL 9.108 FORGAS/FOROIL 4.908 FGI 1.901 IMEX 2007.11 FBOGraph 2.08 FBOExport 1.27 NeoViewer 1.110 NeoFluid 3.62.45.0 DBR Hydrate 2.00 VMG 5.0.2007.316 OLGAS (1992) 1.10 OLGAS - 2 phase 5.0.2.0 Install 4.21 NeoProjectAccounting 2.3 ---------------------------------------------------------------- 1. If the product of the number of equation of state compositions multiplied by the number of components squared is larger than 49950, FORGAS would cause an abort while it wrote the binary interfaction coefficients to the FBO file. This problem has been fixed. 2. For the deliverability curve plot, previously the plot named "Wellhead Pressure vs .." actually referred to the Well Node pressure, not the true wellhead pressure. Now deliverability curves for both the true wellhead pressure and the well node pressure can be plotted. ---------------------------------------------------------------- March 19, 2008 FORGAS/FOROIL 9.107 FORGAS/FOROIL 4.907 FGI 1.901 IMEX 2007.11 FBOGraph 2.08 FBOExport 1.27 NeoViewer 1.110 NeoFluid 3.62.45.0 DBR Hydrate 2.00 VMG 5.0.2007.316 OLGAS (1992) 1.10 OLGAS - 2 phase 5.0.2.0 Install 4.21 NeoProjectAccounting 2.3 ---------------------------------------------------------------- 1. In rare instances in which: a) the specified plant capacity is much lower than the sum of all contract peak demand rates delivering to the plant, b) pool shrinkage or composition tracking has been selected c) the actual deliverability was much lower than the contract rates, then FORGAS may unnecessarily choke wells. This problem has been fixed. This change improves the results from FORGAS Quality Assurance File FG4204.FG. 2. IMEX 2007.11 is now included with the installation. The restart record number has been updated in IMEX8014.DAT to correspond to the new time steps used in this new version of IMEX. MX8014.DAT has also been updated. 3. In extremely rare instances in oil field plants with an oil target, in which the flow rate of oil in the pipe is zero, the mass flow calculations may fail. This has been fixed. 4. The component properties (e.g. boiling point, critical pressure, etc) are now available for exporting to Excel for EOS compositions. Previously this information was available only for fluid property tables and compositions from GEM. 5. Neofluid version 3.62.45.0 has been added. 6. For IMEX oil and GEM wells with wellbore temperature calculations, the specified temperature at the top of the well was used for the static gradient calculations instead of the reservoir temperature. Now the appropriate reservoir temperatures will be used. 7. A method to speed convergence for wellbore temperature calculations has been added. This change improves the results for FORGAS Quality Assurance Files FG7007.FG, FG7008.FG, FG8006.FG, FG8008.FG, FG8012.FG, FG9001.FG, FG9003.FG, FG9004.FG, and FG9103.FG. To accommodate this change, FORGAS Quality Assurance File FG8012.FG was altered to tine-change the zone status of zone A-3D in well A to be not drilled on April 1, 2007. 8. The Forecast for Import table for the wellbore gas lift had an incorrect gas volume listed. This has been fixed and affects the printout of FORGAS Quality Assurance File FG8009.FG 9. The surroundings temperature used for the wellbore temperature calculations may have been incorrect for single phase flow (only). This problem has been fixed. This change affects the results from FORGAS Quality Assurance File FG8006.FG. This problem did not affect multiphase flow (in any direction). 10. The maximum gas viscosity has been increased from 1 cp to 10 cp. ---------------------------------------------------------------- Oct. 3, 2007 FORGAS/FOROIL 9.106 FORGAS/FOROIL 4.906 FGI 1.901 IMEX 2006.10 FBOGraph 2.08 FBOExport 1.27 NeoViewer 1.110 NeoFluid 3.59.38.0 DBR Hydrate 2.00 VMG 5.0.2007.316 OLGAS (1992) 1.10 OLGAS - 2 phase 5.0.2.0 Install 4.03 NeoProjectAccounting 2.2 ---------------------------------------------------------------- 1. In some instances GEM will pass a composition of zero for a particular bottom-hole flowing pressure for a well zone. In rare instances, while interpolating inflow performance points, a non-zero flow rate may have been assigned this empty composition. Previously FORGAS would have ended the forecast with an error message. Now FORGAS checks the composition and will use a nearby non-zero composition for its calculations. 2. While writing the .FBO file, indexes were not set correctly for the following, and thus their plotted or exported values may have been incorrect: - junction condensate viscosity at maximum delivery - pipe gas flow rate at actual production - zone condensate gravity in the input data - zone gas gravity in the input data - well minimum flow rate in mass units (peak, actual and max delivery) - gas code for the pool in the reservoir input data - wobbe index at inlet and exit of facility 3. In oil plants, the calculation of the fuel usage by a pressure loss facility may have caused the termination of the run because the required flash conditions were not previously set up. This has been fixed. 4. While calculating the oil or water rate at a particular gas rate for a gas well which had the gas composition "selected in pool data" and if the reservoir used a fluid property table, an incorrect index was used which may have resulted in problems in the run. This has been fixed. 5. Problems that may have occurred due to accessing the incorrect index of an array have been fixed in the following areas: - print of the compressor capacity curve in the Echo report - reading the well heat transfer data - reading the well time-change data. One result is the time-change of the gas produced by a zone is now used properly which affects the results from FORGAS Quality Assurance File FG9110.FG. - summing report group properties - getting the bottom-hole flowing presure from the inflow performance of a zone for a particular flow rate for a non-target phase in an oil plant - getting the gas heat value for a contract to calculate the corresponding required peak demand gas flow rate. This affects plants using heat value contracts that have multiple contracts. This fix improves the results from FORGAS Quality Assurance Files FG4201.FG, FG4202.FG, FG4203.FG and FG4401.FG. - trying to get properties for liquids from single phase fluid properties - storing the contract shrinkage for later comparison. This fix improves the results from FORGAS Quality Assurance File FG4203.FG FG4301.FG and FG4401.FG. - time-change of the facility connected to a node. This fix improves the results from FORGAS Quality Assurance Files FG8010.FG and FG8013.FG. 6. Previously, for a time-change of a node elevation, FORGAS omitted updating the elevation difference across the pipes immediately upstream of that pipe. This resulted in incorrect hydrostatic pressure losses being computed across those upstream pipes. Now FORGAS updates the elevation difference for all upstream pipes when the node elevation is changed. 7. When plotting items that require a separate selection for each plot file (e.g. mole fraction of a component, well segment data) when using both left and right axes for plotting, the error message "An invalid argument was encountered" may have previously appeared if more than 2 plot files were selected. This problem has been fixed. Note this problem only occurred when both right and left axes are being used. Also, when the right axis was being used, the segment or component names for the left axis were previously not being displayed on the legend. This has also been remedied. 8. The diagnostic print for oil separator calculations will now print the temperature and pressure for all error messages. Previously these values may have been zero or incorrect. 9. The calculation of the critical pressure for a C7+ fraction no longer gives a non-number (Nan) when the molecular weight and specific gravity have not been specified. This fix improves the gross heat and net heat value calculations for equation of state compositions, and fluid property tables. This change affects FORGAS Quality Assurance Files: FG4405.FG, FG6002.FG, FG7007.FG, Fg8006.FG, FG8008.FG, Fg9001.FG, FG9002.FG, FG9003.FG, FG9004.FG, FG9005.FG, and FG9106.FG. Previously, in some cases, a Z value of 1.0 was used to calculate the heat values rather than the Z value computed at standard conditions. ---------------------------------------------------------------- August 13, 2007 FORGAS/FOROIL 9.105 FORGAS/FOROIL 4.905 FGI 1.901 IMEX 2006.10 FBOGraph 2.07 FBOExport 1.27 NeoViewer 1.110 NeoFluid 3.59.38.0 DBR Hydrate 2.00 VMG 5.0.2007.316 OLGAS (1992) 1.10 OLGAS - 2 phase 5.0.2.0 Install 4.03 NeoProjectAccounting 2.2 ---------------------------------------------------------------- 1. Previously, for multiphase injection pipelines, the Beggs and Brill holdup inclination correction was reversed such that uphill flow was using the downhill flow coefficients (and vise versa). This problem has been fixed. As a result of this change the pipeline pressure losses for the injection plant in FORGAS Quality Assurance File FG4205 have been fixed. This only affected pipeline multiphase pressure losses (not wellbore) when one of the Beggs and Brill family of correlations was selected in an injection (not production) plant. 2. Previously when the status of a development zone was time-changed to producer, in rare cases FORGAS may started production from that zone immediately instead of waiting for the development sequence to add that zone. This has been fixed. This change results in well DEF - 2 being reported as a development well immediately after its time-change to a producer in FORGAS Quality Assurance File FG4006.FG. 3. Previously, when calculating the wellbore temperature when gas lift facilites were in the wellbore, the composition used for the gas lift facility was not correctly used for compositional systems. This problem has been fixed. As a result of this change, the temperature and pressure loss calculations for wells with gas lift in FORGAS Quality Assurance file FG8009.FG have been improved. ---------------------------------------------------------------- July 11, 2007 FORGAS/FOROIL 9.104 FORGAS/FOROIL 4.904 FGI 1.901 IMEX 2006.10 FBOGraph 2.07 FBOExport 1.27 NeoViewer 1.110 NeoFluid 3.59.38.0 DBR Hydrate 2.00 VMG 5.0.2007.316 OLGAS (1992) 1.10 OLGAS - 2 phase 5.0.2.0 Install 4.03 NeoProjectAccounting 2.2 ---------------------------------------------------------------- 1. The template files for FBOGraph and FBOExport have been updated to allow export and plotting of the set points passed to GEM. For FBOExport, the inflow performance data points passed by GEM can now be exported. Several items were not previously available for plotting or exporting due to missing spaces in the EXPINDAT.TPL file are now available. 2. When generating the wellhead deliverability curve for a well that has more than one producing zone, now FORGAS will allow bottom-hole flowing pressures up to the highest reservoir pressure of any producing zone. Previously FORGAS would not try flowing pressures higher than that at the well's overall minimum stable flow rate. This change was made to allow very high deliverability wells that have extremely small drawdowns to produce when their maximum flow rate was limited by the user. This change improves the wellhead deliverability curve and reported minimum stable flow rates for some multizone wells in FORGAS quality assurance files: FG7007.FG, FG7008.FG, FG8006.FG, FG8008.FG, FG8012.FG, FG9003.FG and FG9004.FG 3. For a well with multiple producing zones in which only one zone is currently producing, previously FORGAS may have stopped trying to calculate the wellhead deliverability curve once it reached a flow rate less than the minimum stable flow rate. Now FORGAS will try different flow rates. 4. The restart record numbers in GEM files GEM9002.DAT and GEM9003B.DAT have been changed to reflect the new record number from GEM version 2007.10. The FORGAS Quality Assurance files that couple with GEM have also been changed to use the new GEM version number (2007.10). GEM version 2007.10 now enforces shut in conditions specified in the GEM file for 3 wells in FORGAS quality assurance file FG9004.FG. 5. To allow modelling of heavy oils, the maximum oil and overall liquid viscosity allowed has been increased from 20,000 cP (20,000 mPa.s) to 9,999,999 cP (9,999,999 mPa.s). ---------------------------------------------------------------- June 5, 2007 FORGAS/FOROIL 9.103 FORGAS/FOROIL 4.903 FGI 1.901 IMEX 2006.10 FBOGraph 2.07 FBOExport 1.27 NeoViewer 1.110 NeoFluid 3.59.38.0 DBR Hydrate 2.00 VMG 5.0.2007.316 OLGAS (1992) 1.10 OLGAS - 2 phase 5.0.2.0 Install 4.3 NEONET32 1.04 Neobill32 5.31 SpKeyVal 1.9.0.0 NeoProjectAccounting 2.2 ---------------------------------------------------------------- 1. If detailed composition tracking is selected and the only fluid in use for all the wells and imports is a single fluid property table, the forecast may have ended prematurely due to an incorrect gas gravity. The type of composition tracking was not being reported properly in the Echo Report. Both of these problems have been fixed. ---------------------------------------------------------------- May 28, 2007 FORGAS/FOROIL 9.102 FORGAS/FOROIL 4.902 FGI 1.901 IMEX 2006.10 FBOGraph 2.07 FBOExport 1.27 NeoViewer 1.110 NeoFluid 3.59.38.0 DBR Hydrate 2.00 VMG 5.0.2007.316 OLGAS (1992) 1.10 OLGAS - 2 phase 5.0.2.0 Install 4.3 NEONET32 1.04 Neobill32 5.31 SpKeyVal 1.9.0.0 NeoProjectAccounting 2.2 ---------------------------------------------------------------- 1. The OLGAS - 2 phase DLL is now loaded when the OLGAS - 2 phase is selected for the individual well. If the OLGAS - 2 phase correlation was not selected for the plant or in a time-change of the pressure loss equations for the plant or well but was selected for individual wells, the OLGAS - 2 phase calculations would have failed because the library was not loaded. 2. In the FBOExport template files, the item name has been added as one of the choices for variables to export so that the item name appears on each line. Also available is the variable ZZName, which will always appear in the first column of all items selected. 3. Previously, FORGAS may have assumed the overall plant shrinkage was zero when determing the required raw gas inlet rate. This may have happened only under the following conditions: a) gas plant with detailed composition tracking b) plant shrinkage was being computed using extraction efficiencies c) the system could make the required contract peak demand rate if the shrinkage was zero. d) Print Peak Demand was selected for the contract Now FORGAS will always adjust the plant inlet volume to include the calculated plant shrinkage. This problem was introduced in FORGAS version 9.100 (calculation engine 4.900), and was not present in previous versions of FORGAS. As a result of this change all FORGAS Quality Assurance files that use detailed composition tracking have slightly different results. ---------------------------------------------------------------- May 7, 2007 FORGAS/FOROIL 9.101 FORGAS/FOROIL 4.901 FGI 1.901 IMEX 2006.10 FBOGraph 2.07 FBOExport 1.27 NeoViewer 1.110 NeoFluid 3.59.38.0 DBR Hydrate 2.00 VMG 5.0.2007.316 OLGAS (1992) 1.10 OLGAS - 2 phase 5.0.2.0 Install 4.3 NEONET32 1.04 Neobill32 5.31 SpKeyVal 1.9.0.0 NeoProjectAccounting 2.2 ---------------------------------------------------------------- OFFICIAL RELEASE of FORGAS 9.1 See Help, Introduction, Difference Between Version 9.1 to 9.0 for details on previous changes. 1. The well portion of the cumulative contract volumes were not stored properly if there were no report groups and no companies. Now the well cumulative values are always added to the contract totals. 2. For well zones connected to IMEX (oil) in oil plants that have a gas target when only water is being produced (e.g. for coal bed methane), the pumps were effectively turned off because the liquid rate required by the pump calculation routine was set as zero. Now the correct liquid rate is used for the pump calculations. 3. When IMEX (oil) zones are used and when gas is the target phase, now calculated ASTM viscosity coefficients will be used to compute the liquid viscosity. Previously the General equation coefficients were incorrectly specified for the ASTM equation. 4. FORGAS/FOROIL will now ignore specified condensate/gas ratio, condensate viscosity, condensate gravity, water/gas ratio, water/gas ratio versus cumulative production and the change in source of water/gas ratio for all zones connected to IMEX oil reservoirs, even if the target of the plant is gas. Previously time-changes of the water and oil would be done for gas plants, even though the water and oil should always be calculated using the productivity index provided by IMEX. 5. Wellhead chokes for injection wells that inject into IMEX oil reservoirs now produce pressure drop. Previously the reported choke pressure loss was zero for wells connected to IMEX oil reservoirs. 6. Injection well zones producing from IMEX oil reservoirs now use the composition from FORGAS instead of the gravities from IMEX. 7. When the VMG equation of state is validated, FGI defaults to the VMG Advanced Peng-Robinson equation of state. Now FGI will also default the liquid density model to "Equation of State". 8. For a new gas well in a gas plant, for the surface test option, when the user first enters the surface test option, now FGI correctly prompts for sandface n (instead of sandface b) when the default correlation (Conventional C&n) is selected. 9. The bubble point data is no longer stored for IMEX oil wells which have more than 1 zone. Previously the data was stored and then deleted. 10. For IMEX oil wells in oil plants with a gas target, now black oil calculations are used in the wellbore instead of gas gravity calculations. 11. In the wellhead deliverability curve printed in the Echo Report, previously if the temperature was not calculated due to a flow rate of zero, ****** would appear in the tabulated pressures and temperatures. Now the N/A appears in that spot. 12. The ECHO report no longer lists warning messages when a plant is not included in the input data file. 13. The report group and company summaries when there are oil plant wells present now include the proper sign for the gas cumulative production for injection wells. 14. Lift gas for producing wells is now included in the Forecast for Report Group and Company Summary and Forecast Reports. 15. The limit for maximum outlet pressure for downhole pumps now depends on the fluid used when there is only one fluid in the wellbore, rather than using the overall limit for all fluids. 16. For oil plants, when the pressure loss facility did not remove any gas, the contract volumes were not being updated properly. This has been fixed. 17. The gravities for contracts were not being updated properly when field facilities removed fluids when tracking oil or condensate in single contract plants. This resulted in slightly different contract flow rates being reported than were reported for the plant. This problem has been fixed. 18. The cumulative production for non-IMEX wells producing in oil plants was being incremented twice for the last time step (only). This has been fixed. 19. Neofluid version 3.59.38.0 is included in this version which uses VMG version 5.0.2007.316. This version also includes a fix that prevents the failure of the interfacial surface tension calculations for very high water gravities (e.g. water gravities above 2.0). 20. Now FORGAS will check how the computer's date is displayed (e.g. mm/dd/yyyy or dd/mm/yyyy or yyyy/mm/dd) and use that format while passing dates to MBAL. Previously FORGAS assumed a dd/mm/yyyy format, which could lead to incorrect forecasts when a different date format was being used than what MBAL expected. 21. Previously, for detailed composition tracking in which only gas gravity was being tracked, the sales gas values in the Forecast for Report Group table were printed as zeros. Now the correct actual production sales gas volumes are printed. 22. The mass of gas, water and oil is now computed for ECLIPSE wells while the pressure losses are being calculated. Previously, the mass was not calculated until after the summary tables were printed, and thus fuel usage of compressors and pressure loss facilities in plants using black oil or gas gravity tracking was incorrectly reported as zero. ---------------------------------------------------------------- April 9, 2007 FORGAS/FOROIL 9.100 FORGAS/FOROIL 4.900 IMEX 2006.10 FGI 1.900 FBOGraph 2.07 FBOExport 1.27 NeoViewer 1.110 NeoFluid 3.56.30.0 DBR Hydrate 2.00 VMG 4.3.60510 OLGAS (1992) 1.10 OLGAS - 2 phase 5.0.2.0 Install 4.3 NEONET32 1.04 Neobill32 5.31 SpKeyVal 1.9.0.0 NeoProjectAccounting 2.2 ---------------------------------------------------------------- 1. The specific gravity of wellbore condensate was increased from 0.65 to 0.66 for Quality Assurance File FG4003.FG, to avoid being reset to a default value when its value is less than 0.66. Previous changes can be viewed in UPDATEFG.FUL.