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Target Specifications & Thermal Growth. Targets vs. Growth: Difference?. - PowerPoint PPT Presentation
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Target SpecificationsTarget Specifications&&
Thermal GrowthThermal Growth
Target SpecificationsTarget Specifications&&
Thermal GrowthThermal Growth
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Targets vs. Growth: Difference?Targets vs. Growth: Difference?Targets vs. Growth: Difference?Targets vs. Growth: Difference?
Target SpecificationsTarget Specifications are the prescribed misalignment to be set at the couplingat the coupling in the stopped and unloaded condition, to compensate for the anticipated changes that will occur in the alignment as the machines are put in operation and reach their fully loaded operating condition.
Thermal GrowthThermal Growth values represent the amount of positional change the shaft centerline is expected to undergo at the at the machine supportsmachine supports as the machines are put in operation and reach their fully loaded operating condition.
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Targets & Thermal GrowthTargets & Thermal GrowthTargets & Thermal GrowthTargets & Thermal Growth
Only the best laser shaft alignment systems allow you to input both types of data, simultaneously if necessarysimultaneously if necessary, for all machines in the train.
Only the best laser shaft alignment systems will calculate the thermal growth values for you, based on the observed temperature changes of the machines.
Why is this important?
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Targets & Thermal GrowthTargets & Thermal GrowthTargets & Thermal GrowthTargets & Thermal Growth
Because:
Some machine vendors won’t supply you any data at all.
Some machine vendors will only supply one type of dataor the other.
The vendor of the driver may only supply thermal growthvalues for his machine.
The vendor of the driven machine may supply target specifications for the driver, instead of thermal growth valuesor targets for his machine.
How can you deal with both sets of data together?
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This is the starting condition, cold.This is the ending condition, hot.
Thermal Growth: An ExampleThermal Growth: An ExampleThermal Growth: An ExampleThermal Growth: An Example
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Thermal Growth: An ExampleThermal Growth: An ExampleThermal Growth: An ExampleThermal Growth: An Example
The starting condition, cold.
Offset = 0 mils.Angularity = 0 mils/inch.
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Calculating Thermal GrowthCalculating Thermal GrowthCalculating Thermal GrowthCalculating Thermal Growth
Thermal Growth = T·L·C
Where: T = Change in temperature (∆t), in deg. F.L = Height of shaft centerline above shim
plane.C = Coefficient of expansion.
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Calculating Thermal GrowthCalculating Thermal GrowthCalculating Thermal GrowthCalculating Thermal Growth
Thermal Growth = T·L·C
Compressor:
T Cold = 80° F. 80° F. T Hot = 200° F. 240° F.
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Calculating Thermal GrowthCalculating Thermal GrowthCalculating Thermal GrowthCalculating Thermal Growth
Thermal Growth = T·L·C
Compressor:
T Cold = 80° F. = 80° F. T Hot = 200° F. = 240° F.L = 20″C = 0.0059 mils/inch/°F (Cast iron)
Coefficients of Expansion(mils/inch/°F)
Aluminum: 0.0126Bronze: 0.0100Cast Iron, gray: 0.0059Mild Steel, ductile iron: 0.0063Stainless steel: 0.0074
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Calculating Thermal GrowthCalculating Thermal GrowthCalculating Thermal GrowthCalculating Thermal Growth
Thermal Growth = T·L·C
Compressor:
T Cold = 80° F. = 80° F. T Hot = 200° F. = 240° F.L = 20″C = 0.0059 mils/inch/°F (Cast iron)
14.2
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Calculating Thermal GrowthCalculating Thermal GrowthCalculating Thermal GrowthCalculating Thermal Growth
Thermal Growth = T·L·C
Compressor:
T Cold = 80° F. = 80° F. T Hot = 200° F. = 240° F.L = 20″C = 0.0059 mils/inch/°F (Cast iron)
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Calculating Resulting Calculating Resulting MisalignmentMisalignmentCalculating Resulting Calculating Resulting MisalignmentMisalignment
Thermal Growth = How much misalignment at coupling?
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Angularity = Rise/Run.Offset = Known Offset + Angularity × Run to desired location.
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Calculating Resulting Calculating Resulting MisalignmentMisalignmentCalculating Resulting Calculating Resulting MisalignmentMisalignment
Thermal Growth projected to the Coupling:Thermal Growth projected to the Coupling: Calculated automatically
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Calculating Resulting Calculating Resulting Misalignment TargetsMisalignment TargetsCalculating Resulting Calculating Resulting Misalignment TargetsMisalignment Targets
Thermal Growth = How much misalignment? Calculate targets directly:
Gsb = Growth, back feet, left machine. Gsf = Growth, front feet, left machine.Gmf = Growth, front feet, right machine.Gmf = Growth, back feet, right machine.a = Distance back feet to front feet, left machine.b = Distance front feet to coupling center, left machine.c = Distance front feet to coupling center, right machine.d = Distance back feet to front feet, right machine.Dia: = Coupling diameter (10˝).
Vertical Offset:
Vertical Angularity:
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Calculating Target SpecsCalculating Target SpecsCalculating Target SpecsCalculating Target SpecsTarget specs at the coupling:Target specs at the coupling: Calculated automatically from relative difference in thermal growth between left and right machines.
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Calculating Target SpecsCalculating Target SpecsCalculating Target SpecsCalculating Target SpecsTarget specs at the coupling:Target specs at the coupling: If you would prefer to enter target specifications directly, you may easily do so:
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Thermal Growth & Target SpecsThermal Growth & Target SpecsThermal Growth & Target SpecsThermal Growth & Target Specs
•Enter thermal growth for any or all machines in the train.•Enter targets and thermal growth separately or simultaneously, as needed.•Enter targets for left or right side of the coupling, or both, for all couplings.•Built-in thermal growth calculator: Simply input observed changes in temperature,
machine material and dimensions.•Automatically calculates coupling targets from thermal growth, or from dial
indicator targets.
