Emerson VSSG, VSG manual Installation, Hot Air Recirculation

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HOT AIR RECIRCULATION

Section 3 • Installation

HOT AIR RECIRCULATION

There are two situations where hot recirculation could occur.

•Intake velocity of the cooler is higher than the dis- charge velocity

•Environmental issues such as strong cross winds which is installation specific

We addressed how to minimize the opportunity for hot air recirculation involving the operation of the air cool- ers under the guidelines for the Free Flow section above. However, environmental hot air recirculation is some- thing that is outside of the control of the cooler manu- facturer. If the site has the potential for strong cross winds or tunneling then you may want to consider the following items to minimize the potential of hot air recir- culation due to the environment.

•All air coolers should discharge at the same elevation.

•If feasible all of the air coolers in a common area should be placed as close to the next cooler as possible.

Unfortunately this comes with a cost. By reducing the in- take perimeter available, the leg height increases, which is a cost. In addition there is no guarantee that hot air recirculation can be eliminated due to environmental issues.

Discharge Elevation

In order to minimize the potential for hot air recircula- tion, it is recommended to install the air coolers so that they all discharge at the same elevation. This is impor- tant because not all air coolers have the same plenum heights. You can satisfy the leg height requirements by the calculation above but not satisfy the requirements for discharge elevation. Based on the size of the cool- ers above, cooler 1 has a plenum height of 36”, cooler 2 has a plenum height of 42”, and cooler 3 has a plenum height of 54”. Plenum heights are calculated from the standard of a 45 degree dispersion angle in API 661. If you would like more details on this calculation please contact engineering.

As you can see in Figure 3-13 in the not preferred con- figuration. the leg height requirement in the first cal- culation is satisfied. However, the coolers are not at the same discharge elevation. This could be an issue if there is a cross wind from left to right. Cooler 3 could block the discharge air flow from coolers 1 and 2 and recirculate it back down to the intake of the coolers. The best way to address this is to increase the leg heights on coolers 1 and 2 as shown in the preferred configuration.

This is especially critical if all of the air coolers are not place as close together as possible.

Cooler Placement and Spacing

The concern about cooler placement as far as proximity from one another has to do with the potential for hot air recirculation due to cross winds. Let’s look at only having coolers 1 and 3 in the same area. The leg height requirement of cooler 1 is 3.23ft so we would use a 4ft leg height. The leg height requirement for cooler 3 is 4.61ft but we would put a 7 foot leg height on the cooler due to size and for serviceability. Figure F. shows this installation.

In this case, if you get a strong cross wind from left to right there is the potential that the discharge coming from the top of cooler 1 could easily be pushed into the intake of cooler 3. Thus, in Figure 3-14, the not preferred configuration is more susceptible to the potential of hot air recirculation due to the environment and is not rec- ommended. The preferred configuration is the recom- mended installation of the coolers with a space between them.

All of the information provided is a general guideline for installing multiple air coolers in a common area. If you minimally follow all of the Free Flow requirements and keep the air coolers discharging at the same elevation then you have a good basis for site layout.

Sometimes due to extenuating circumstances, the above guidelines cannot be followed. Please contact en- gineering to discuss remedies to accommodate different configurations.

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VSG/VSSG • Installation, Operation and Maintenance Manual •Vilter/Emerson • 35391SSG

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Page 33 Page 35
Contents Installation, operation & maintenance manual VSG/VSSG compressor unitPage VSG/VSSG Standard Vilter Warranty Statement READ CAREFULLY BEFORE INSTALLING AND STARTING YOUR COMPRESSOR Important MessageVilter Manufacturing LLC Section Title Table of ContentsSection 3 Installation Section 1 General InformationSection Number Section 5 Maintenance/ServiceSection 6 Troubleshooting Section 4 OperationAppendices Section 7 Warranty and PartsList of Tables and Figures Table/FigureFigure 3-12. Installation of Coolers - Next to Buildling Section 1 General Information How To Use This Manual Section 1 General Information Gas Compressor Unit Model Designations Figure 1-1. Gas Compressor Unit Model DesignationSection 1 General Information System Unit Identification Compressor Unit Component Identification Section 1 General InformationFigure 1-2. Gas Compressor Unit Components 1 of Figure 1-2. Gas Compressor Unit Components 2 of Section 1 General Information Component Identification Continued Figure 1-2. Gas Compressor Unit Components 3 ofSection 1 General Information Piping & Identification Component Tags Position Transmitter Symbols and Identifications3-Way Thermostatic Valve High Side Float Valve Steady-Mount Bulb & Capillary 1 - 10 / Blank Oil Life and Oil Flow Section 2 Theory of OperationGas Flow Figure 2-1. Gas Compressor Unit P&IDControl System RTDs and Pressure TransducersThis is a continuous cycle Rigging and Lifting of Compressor Unit Section 3 InstallationDelivery Inspection Figure 3-1. Rigging and Lifting PointsLong Term Storage Recommendations The following are recommendations regarding long term storageRecommended Onsite Tools Compressor Unit Inspections Prior to Storage or InstallationAIR COOLED OIL COOLERS LONG TERM STORAGE LOG Compressor has been placed in operation as ofConsiderations Prior to Starting FoundationFoundation Materials Building the FoundationCompressor Unit Installation of both Check the ability of the soil to carry the loadLeveling and Grouting recommendations for setting, precautions, mixing, andAdditional Information Codes and Standards LEVEL Figure 3-6. Housekeeping Pad Dimension Detail - Top View2 - # CLOSED TIES CENTER LINE 5 - # 6 VERT COMPRESSOR UNIT HOUSEKEEPING PADSPiping 010Ä5*4+0- 214176 4%1//0&& 14 175-2+0 10%46 $#5Fz lbf Table 3-2. Maximum Allowable Flange LoadsNozzle Dia. in Fy lbfONE FAN DIAMETER NOT PREFERRED HOT AIR RECIRCULATION Figure 3-13. Discharge Elevation of Coolers Figure 3-14. Cooler Placement and SpacingPREFERRED Unit Oil Charging and Priming Pressure TestingInitial Oil Charging Using Non -Vilter Oils Do not hydro test compressur unit. Failure to complyMinimum Operating Level Normal Operating Level Maximum NON-Operating LevelBypass Valve OIL MIXING CLOSESUCTION INLET OPEN VALVEPriming Remote Oil Cooler and Piping Section 3 InstallationInitial Oil Charging REMOTEOIL FILTER OPEN SUCTION INLETMOTOR Section 3 Installation Pre Start-Up Pre Start-Up Checklist15. Verify that all valves are in the open position Section 3 Installation Start-Up Oil Inspection Section 4 OperationOperation Dual Oil FiltersStarting, Stopping and Restarting the Compressor Starting Control System CalibrationStopping/Restarting Calibrate Slide Valve ActuatorsFigure 4-2. Actuator Assembly Section 4 Operation Figure 4-4. Slide Valve Calibration Screen Compact Logix PLC Figure 4-5. Photo-chopperAngle/Slide Travel Table 4-1. Command Shaft Rotation SpecificationsCapacity Oil Temperature Control Valve Oil Mixing Valve Operation 18. Press the “Set Max” buttonFail Position Purging with Dry Nitrogen 10. Close discharge bleed valve while still purging Pressure Indicator Purging with Dry GasOIL SEPARATOR Section 4 Operation Figure 4-12. Suction Bypass Valve and Equalizing Solenoid Suction Oil Figure 4-13. Suction Oil Charging ValveCoalescing Oil Return Line Setup Unit Table 5-1. Maintenance/Service ScheduleOil Circuit ControlMaintaining Proper Operation Section 5 Maintenance/ServiceMaintenance/Service Compressor Unit Isolation forCompressor Unit Leak Check sample for analysis. For an example, see Figure 5-2. Fill Oil System Components Oil SamplingUse Vilter Oil Analysis Kit VPN 3097A to collect an oil Send samples immediately to the oil analysis lab afterOil Charging Dual Oil Filter Assembly Oil Filter ReplacementSingle Oil Filter Assembly Oil DrainingVent Valve Drain Valve Inlet Shut-Off Valves Coalescing Filter Coalescing Filter ReplacementCentering Strap Oil Pump Strainer View From Back of Oil Pump StrainerTable 5-3. Shaft and Hub Distances Drive Coupling Form-Flex BPU Hub InstallationSize Drive Center Member Installation and Alignment 17. Install set screw in hub cap to secure key in keyway of shaftTable 5-4. Hub Clamp Bolt and Set Screw Torque Specifications Table 5-5. Disc Pack Installation Torque SpecificationsAngular Alignment Drive Coupling Type C Sure-Flex Replacement Drive Coupling Form-Flex BPU Center Member and Hub RemovalCompressor Replacement Table 5-6. Clamping Bolts and Set Screw Torque SpecificationsLock Washer Compressor Shaft Bearing Float Inspections Figure 5-11. Bearing Axial Float InspectionFigure 5-12. Bearing Radial Float Inspection Gate Rotor Float and Gate Rotor Bearing Float InspectionTable 5-7. Maximum Bearing Float Figure 5-13. Gate Rotor FloatApplied Force Rigidly attach dial indicator Use bolt for fulcurm Table 5-8. Gate Rotor FloatFigure 5-14. Gate Rotor Bearing Float Gate rotor bearing float being measuredSection 5 Maintenance/Service Gate Rotor and Support Clearance Figure 5-15. Gate Rotor and Support Clearance - Minimum ClearancesGate Rotor Support Gate Rotor Figure 5-16. Gate Rotor and Support Clearance - MeasuringGate Rotor Support Gate Rotor Gate Rotor Support Gate Rotor Straight Edge Straight Edge Straight EdgeVSG 301-701 Compressors Gate Rotor Assembly Replacement All VSG & VSSG Compressors ExceptTable 5-9. Gate Rotor Tool Sets Figure 5-17. Gate Rotor Assembly Removal and Tools Figure 5-18. Gate Rotor Assembly RemovalFigure 5-19. Gate Rotor Assembly and Tools Figure 5-20. Gate Rotor and Shelf ClearanceGate Rotor Assembly Replacement VSG 301-701 Compressors ONLY Figure 5-21. Gate Rotor Assembly BreakdownFigure 5-23. Gate Rotor and Shelf Clearance Figure 5-22. Gate Rotor Thrust BearingFigure 5-25. Gate Rotor Blade Installation Gate Rotor DisassemblyFigure 5-24. Gate Rotor Blade Assembly Figure 5-27. Thrust Bearing Installation Figure 5-26. Gate Rotor Thrust BearingSlide Valve Actuator Assembly Replacement Figure 5-28. Roller Bearing AssemblyCommand Shaft Seal Replacement Command Shaft Assembly ReplacementFigure 5-29. Command Shaft Seal Figure 5-30. Command Shaft Seal Installation Solution Section 6 TroubleshootingProblem Table 6-1. Slide Valve Actuator Troubleshooting Guide 1 ofTable 6-1. Slide Valve Actuator Troubleshooting Guide 2 of Meaning Flash PatternTable 6-2. Slide Valve Actuator LED Blink Codes* 1 of calibrate the actuator. If this error has occurred and the cause was er before the calibration procedure was completed. The actuatorwill not move while this error code is displayed. To clear the error not the loss of 24V power during calibration, possible causes areTable 6-3. Troubleshooting Guide - General Problems & Solutions 1 of Table 6-3. Troubleshooting Guide - General Problems & Solutions 2 of Table 6-3. Troubleshooting Guide - General Problems & Solutions 3 of 6 - 8 / Blank On Site Service Support Section 7 Warranty and PartsWarranty Claim Processing Warranty does not cover labor and extraneous expensesRemanufactured Gas Bare Shaft Compressor Process Request a “VSG Single Screw Compressor Rebuild Form”Torque Specifications ft-lbs Appendix A Torque SpecificationsTorque Specifications for 17-4 Stainless Steel Fasteners ft-lbs Appendix B Motor Compressor - General Storage Instructions PRODUCT ANALYSIS REPORT Appendix C Oil Analysis ReportEvaluation No Action RequiredAppendix D Recommended Header Piping OUTLET ON TOP Appendix E Recommended Remote Air Cooled Oil Cooler PipingINLET ON BOTTOM Blank
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