1、API Standard ParagraphsRotordynamic Tutorial: LateralCritical Speeds, UnbalanceResponse, Stability, TrainTorsionals, and Rotor BalancingAPI RECOMMENDED PRACTICE 684SECOND EDITION, AUGUST 2005REAFFIRMED, NOVEMBER 2010API Standard ParagraphsRotordynamic Tutorial: LateralCritical Speeds, UnbalanceRespo
2、nse, Stability, TrainTorsionals, and Rotor BalancingDownstream SegmentAPI RECOMMENDED PRACTICE 684SECOND EDITION, AUGUST 2005REAFFIRMED, NOVEMBER 2010SPECIAL NOTESAPI publications necessarily address problems of a general nature. With respect to partic-ular circumstances, local, state, and federal l
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16、n manager,American Petroleum Institute, 1220 L Street, N.W., Washington, D.C. 20005, stan-dardsapi.org.iiiCONTENTSPage1 OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-11.1 Introduction . . . . . . .
17、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-11.2 Organization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-11.3 Standard Paragraphs . . . . .
18、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-11.4 Definitions and References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-11.5 Fundamental Concepts Of Rotating Equipment Vibrat
19、ions . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-12 LATERAL ROTORDYNAMICS 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-12.2 Rotor Bearing System Modeling. . . . . . . . . . . . . . . .
20、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-12.3 Rotor Modeling Methods and Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-12.4 Support Stiffness Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
21、 . . . . . . . . . . . . . . .2-132.5 Journal Bearing Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-222.6 Seal Types and Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
22、. . .2-432.7 Elements of a Standard Rotordynamics Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-582.8 Machinery Specific Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-712.9 API Testing and Results. . . . .
23、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-972.10 Standard Paragraph Sections for Lateral Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1053 STABILITY ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . .
24、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-13.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-13.2 Rotor Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-43.3 Journal Bearings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-53.4 Seals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
26、. . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-253.5 Excitation Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-363.6 Support Stiffness Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
27、 . . . . . . . . . . . . . . . . . . . . .3-433.7 Experience Plots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-483.8 Machinery Specific Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
28、 . . . . . . . . .3-513.9 Solving Stability Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-673.10 Indentifying Fluid Induced Instabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-723.11 St
29、ability of Testing Machinery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-733.12 Standard Paragraph Sections for Stability Analysis SP6.8.5 SP6.8.6 . . . . . . . . . . . . . . . . . .3-784 TORSIONAL ANALYSIS . . . . . . . . . . . . . . . . . . .
30、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-14.0 Introduction and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-14.1 Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-24.2 Machinery Specific Modeling Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-154.3 Reciprocating Machinery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
32、. . . . . . . . . . . . . .4-204.4 Torsional Analysis Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-274.5 Torsional Excitation Sources from Rotating Machinery . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-424.6 Fatigue Anal
33、ysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-494.7 Contents of a Torsional Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-524.8 Field Testing to Determine Tors
34、ional Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-544.9 TorsionalLateral Vibration Coupling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-574.10 API Document Paragraphs on Torsional Vibration. . . . . . . . . . . . . . . .
35、 . . . . . . . . . . . . . . . . . .4-575 BALANCING OF MACHINERY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-15.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
36、 . . . . . . . . . .5-15.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-15.3 Balancing Machines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
37、 . . . . .5-75.4 Balancing Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-11vPageFigures1-1 Simple Mass-spring-damper System . 1-21-2 Amplitude Ratio Versus Excitation Frequency (Rotation Speed). 1-31-3 Phase Angle Versus E
38、xcitation Frequency. 1-31-4 Response of a Spring-mass System to Transient (Stable). 1-41-5 Response of a Spring-mass System to Transient (Unstable). 1-41-6 Jeffcott Form for Rotor Model. 1-51-7 Simplified Model of a Beam-type Rotating Machine . 1-51-8 Simplified Model of a Beam-type Rotating Machine
39、 with Damping. 1-51-9 Spring-Mass-Damper Model of Beam Type Rotating Machine . 1-61-10 Synchronous Response of Beam Type Machine for Various Shaft Stiffness Values 1-62-1 Schematic of a Lumped Parameter Rotor Model 2-32-2 3D Finite Element Model of a Complex Geometry Rotating Component . 2-52-3 Elas
40、tic Modulus vs. Temperature. 2-72-4 Rotor Model Cross-section of an Eight-Stage 12 MW (16,000 HP) Steam Turbine . 2-72-5 Turboexpander with Curvic Coupling Fits 2-82-6 Turbocompressor with Rabbet and Curvic Coupling Fits. 2-82-7 Modeling of Curvic Coupling Joints . 2-82-8 Train Lateral Model 2-102-9
41、 Train Lateral Guideline Diagram (Wjnl= Static Bearing Reaction) . 2-102-10 Train Lateral Mode Shapes 2-112-11 Equivalent Coupling Model . 2-122-12 Steam Turbine Support Schematic. 2-142-13 Journal Bearing Fluid Film and Flexible Support Model . 2-152-14 Single Degree of Freedom Flexible Support Mod
42、el 2-152-15 Dynamic Stiffness Analysis Diagram 2-162-16 Exhaust End Dynamic Compliance Plots 2-172-17 Steam End Test Stand Response . 2-182-18 Exhaust End Test Stand Response 2-182-19 Exhaust End Constant Stiffness Support Model 2-192-20 Steam End Dynamic Compliance Support Model . 2-202-21 Steam En
43、d Analytical Results, Dynamic Compliance Model 2-212-22 Journal Bearing Hydrodynamic Film . 2-232-23 Two Axial Groove Bearing . 2-232-24 Spring Stiffness . 2-242-25 Journal Bearing Stiffness and Damping . 2-242-26 Pressure Dam Bearing . 2-252-27 Pressure Dam BearingTop and Bottom Pads 2-262-28 Ellip
44、tical Bearing . 2-272-29 Offset Half Bearing . 2-272-30 Taper Land Bearing with Three Tapered Pockets . 2-282-31 Multi-Lobe Bearing with Three Preloaded, Offset Lobes 2-282-32 5-Pad Tilting Pad Bearing Schematic . 2-302-33 Zero Preloaded Pad . 2-312-34 Preloaded Pad 2-312-35 Negative Preloaded Pad .
45、 2-322-36 Stiffness and Damping vs. Preload and Bearing Clearance, 4-pad Bearing 2-332-37 Stiffness and Damping vs. Preload and L/D Ratio, 4-pad Bearing 2-342-38 Lunds Data vs. Experimental . 2-352-39 Jones and Martin Data vs. Experimental 2-352-40 Actual Test Stand Response, 3-axial Groove Bearings
46、 2-362-41 Analytically Predicted Response 2-372-42 Actual Test Stand Response, 4-pad Tilting Pad Bearings 2-382-43 Analytically Predicted Response, Various Bearing Designs 2-392-44 Induction Motor Test Stand Response, Tilting Pad Bearings . 2-39viPage2-45 Induction Motor Analytical Response, Tilting
47、 Pad Bearings . 2-402-46 Induction Motor Analytical Response, Elliptical Bearings 2-402-47 Induction Motor Test Stand Response, Elliptical Bearings 2-412-48 Oil Bushing Breakdown Seal 2-452-49 Pressures Experienced by the Outer Floating Ring Seal 2-452-50 Mid-span Rotor Unbalance Response of a High
48、Pressure Centrifugal Compressor for Different Suction Pressures at Start-Up. 2-462-51 Mechanical (Contact) Shaft Seal 2-472-52 Liquid-film Shaft Seal with Cylindrical Bushing . 2-472-53 Liquid-film Shaft Seal with Pumping Bushing 2-482-54 Compressor Labyrinth Seals . 2-492-55 Typical Turbine Shaft S
49、eal ArrangementHP End . 2-492-56 Honeycomb Seal . 2-502-57 Pocket Damper Seal 2-502-58 Segmented-ring Shaft Seal 2-512-59 Self-acting Gas Seal 2-522-60 Swirl and Thrust Brakes Used in High-Pressure Compressors 27 2-522-61 Measured Natural Frequency and Damping Showing a Drop of the First Bending Mode of the Shaft 27. 2-542-62 Change in First Critical Speed Frequency Due to Influential Gas Seals . 2-552-63 Change in Separation Margin From Unbalance Response Calculation . 2-552-64 Labyrinth Seal Bulk Flow Control Volume Approaches 2-562-65 Undamped Critical Speed Map . 2-602-66 Mode
