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3600 Marine Engine Application and Installation Guide

● Ancillary Equipment

LEKM8470 8-98

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Ancillary Equipment

Marine Gears Couplings Torsional Limits Propellers Fixed Pitch Controllable Pitch

Marine Gears between the shafting, gearbox, and main engines. Collision chocks are normally Reversing marine gears are used: fitted at the corners of the gearbox mounting flange to maintain alignment • To match relatively small, economical in the event of an accident. medium speed engines to the low propeller rpm necessary for high Care should be taken in selecting the efficiency. capacity of the low speed output bearing. • To reverse the propeller rotation for It must be capable of carrying loads the non-reversing 3600 Family of imposed by the line shaft or tail shaft Engines. directly connected to the low speed coupling. Advise the gear manufacturer Marine gears are selected to transmit if a propeller blade actuating box is to be rated engine horsepower (plus overload mounted on the gearbox, or if auxiliary if required) at rated rpm. Design the equipment is to be driven from power gear to meet appropriate classification takeoffs on the gear housing. society rules. Inspection and Certification may be required. Advise Carefully review the final arrangement the gear manufacturer of expected of the gearbox in the engine room for the adverse conditions, such as operation in best overall installation. Space must be ice. available for service and maintenance. The following are examples of typical Main engine marine gears are normally arrangements used with the 3600 single or double reduction, with the ratio Family of Engines: of input and output speeds selected to meet the propeller design rpm. The • Single input/single output, horizontal gears are either uni-directional or offset, reversing. See Figure 1. reverse reduction depending on the type • Single input/single output, vertical of propeller selected (either fixed or offset, reversing. See Figure 2. controllable pitch). • Single input/single output, concentric, reversing. See Figure 3. Pinion and bull gear bearings are either sleeve or antifriction. The thrust bearing • Twin input/single output, horizontal- is normally built into the gear casing vertical offset, non-reversing. See and sized to take the reactive thrust of Figure 4. the propeller. • Twin input/single output, horizontal offset, non-reversing. See Figure 5. Clutches are normally pneumatic or hydraulically actuated, straight The Torsional and System Stability engagement, or slip type. Ahead and Analysis section within General astern clutches are required if a Information in this guide describes the reversing gear is used. required torsional analysis. The marine gear manufacturer must provide data. The gear box lubrication and cooling oil system is normally self-contained and fitted on the gearbox assembly. It is also used for hydraulic clutch actuation.

The marine gear is mounted to a rugged fabricated steel foundation securely welded to the ship’s structure; refer to the Mounting and Alignment section of this guide. The gearbox is bolted to its foundation using either steel or epoxy resin chocks to ensure alignment

5

Single Input/Single Output Horizontal Offset, Reversing

Figure 1

6 Vertical Offset, Reversing Vertical Single Input/Single Output

Figure 2

7 Concentric, Reversing Single Input/Single Output

Figure 3

8 ertical Offset Non-Reversing Twin Input/Single Output Twin Horizontal V

Figure 4

9 Non-Reversing Horizontal Offset Twin Input/Single Output Twin

Figure 5

10

Couplings used. The first uses elastomer elements to provide both torsional flexibility and A propulsion engine’s power damping. Figure 6 illustrates a typical transmission is through a flexible example of this coupling design. The coupling, or a combined flexible coupling number of required elements depends on and clutch mounted on the flywheel. A the torsional vibration calculation. In heavy coupling can be mounted on the addition, engines with a resilient flywheel or shaft flange without mounting system require a balanced intermediate bearings. The type of coupling. flexible coupling to be used for each installation must be determined on the Note: The application will determine the basis of torsional vibration calculations. coupling size. Two fundamental coupling types are 03 HIGH INERTIA FLYWHEEL MOUNTING FACE 170 ONE, TWO OR THREE ELASTIC ELEMENTS REQUIRED DEPENDING ON TORSIONAL VIBRATION ANALYSIS

FLYWHEEL REF. ¯1025 BOLT CIRCLE ¯ 24 BOLT HOLE 32 PLACES

CENTERLINE OF ¯259mm ¯1070mm

01 01 BORE*

REAR FACE OF CRANKSHAFT ADAPTER 03

DETAIL OF COUPLING SCALE NONE * HUB MACHINED TO CUSTOMER SPECIFICATION Figure 6

11 A second type of coupling utilizes leaf or by oil displacement (dash pot). Figure 7 coil springs for torsional flexibility. illustrates a typical example of this Hydrodynamic damping is accomplished coupling type. orsional Coupling ype T (c) 1991 by Eaton Corp. Spring T

Figure 7

12 The selection of a coupling depends on • Select coupling that meets all the the driveline configuration (gearbox, following criteria: shafting, propeller, etc.). A complete set Coupling vibratory torque limits of driveline data is required to properly Crankshaft vibration limits select a coupling. A Torsional Vibration • Analyze alternative couplings until Analysis (TVA) must be performed to all of the above conditions are met. confirm the coupling selection. The information required by Caterpillar to Use torsional limit stops (coupling locks perform a TVA is shown in Figure 8. if operated beyond limits) on couplings Also see Torsional Vibration Analysis providing the sole source of transmitting under the General Information section of propulsive power. A single screw vessel this guide. is an example. The vessels should have a take-home feature if the coupling fails. Torsional Limits The following guidelines should be used Note: Germanischer Lloyd and Bureau in the coupling selection process: Veritas may not permit a torsional limit stop because of potentially severe • Crankshaft Amplitude Limits: torsional problems when the propulsion Misfire calculated using #1 engine system is operated with a failed coupling. misfiring. Individual order analysis with or without misfire. Propellers Amplitude limits at front of • Do not exceed ± 1.0° for 0.5 order Fixed Pitch • Do not exceed ± 1.0° for 1st order The dimensions of fixed pitch (FP) • Do not exceed ± 0.25° for 1.5 order propellers must be carefully reviewed for • Do not exceed ± 0.15° for all orders each application. They control the level above 1.5 at front of crank of engine power that can be used in a • Do not exceed ± 21 MPa (3000 psi) ship installation. crankshaft stress for each engine order Factors influencing the design are: • Vibratory Torque: Limit of coupling • Propulsion resistance of the ship with #1 cylinder misfire increases with time. • Coupling Power Loss: Limit of • Wake factor for the ship increases coupling with #1 cylinder misfire with time. Coupling Selection • Propeller blade frictional resistance • Develop a coupling selection matrix in water increases with time. based on: • Bollard pull requires higher torque Engine model than free running. Power • Propellers rotating in ice require Inertia - driveline data higher torque. Ambient temperature 45°C Fixed pitch propellers are normally 60°C designed to absorb 85% of the Maximum Application Continuous Rating (MCR), or 90% of the Main Propulsion or Ship Continuous Service Rating (CSR) at Service Generator Set normal speed when the ship is on trial at specified speed and draft (see Figure 9).

Consider the accessory equipment power requirements for shaft generators or hydraulic pumps when sizing FP propellers.

13 3600 Torsional Vibration Analysis Request

Project Number ______Project/Customer Name ______Dealer Name ______

The information on this form is to be used for a specific request for a torsional vibration analysis on the above 3600 Diesel Engine application. Please provide a timely verbal response followed by a written report to the responsible project engineer. The following information describes the major components and performance data for this application: Engine Model and Rating: E29 ______(36 ______); ______kW (______bhp) Low Idle rpm ______Rated Speed rpm ______Engine Regulation: Isochronous (Y/N) ______, or Percent Droop ______%

Application Specifics: ______(quantity engines -- custom base -- front driven equipment, etc.) Engine Room Maximum Ambient Temperature ______Generator ( ____ ); and/or Marine Gear ( ____ ); plus Other Driven Equipment ( ____ ) Supplier Name and Model Number ______Rotating Inertia/Drawing(s) ______Rotating Stiffness/Shaft Drawing(s) ______Gearbox Drawing ______Propeller Inertia ______Description (e.g. two bearing or single bearing) ______(attached are supplier data sheets) Part Numbers of Components: Flywheel Group ______Coupling Group ______Drive Group ______Damper Group ______Ring Gear Group ______Other Groups ______3161 Governor Group ______Heinzmann Governor ______EGB29P Electronic Control Group ______Actuator Assembly ______

Engine Ship Date (RTS) ______Torsional Completion Date Required ______Caterpillar Project Engineer ______(Revised 4-25-97)

Figure 8

14 Propeller Design Match Points 100 100

75 75 Zone Of Limited Operations

50 50

Clutch In Speed Range Percent of Rated Engine Power

25 25 Percent of Rated Engine Power

Min. Idle Zone Of Speed Continuous Operation

10 20 30 40 50 60 70 80 90 100 110 Percent of Rated Engine Speed

CURVE #1 (MCR) CURVE #2 (PROPELLER @ 85% OF MCR) CURVE #3 (CSR) Figure 9 CURVE #4 (PROPELLER @ 90% OF CSR)

Fishing or towing ships should use a Figure 8 shows the permissible propeller designed for 85% MCR of the operating range for a FP propeller engine, the normal speed for fishing or installation and the design point at 85% bollard pull or at towing speed. The MCR at nominal speed. The minimum absorbed power at free running and speed is decided separately for each normal speed is usually lower (about application. The speed control system 65% to 85%) than the output at fishing should give a boost signal to the speed or bollard pull. actuator to prevent engine speed from decreasing when clutching in. Select the Consult Caterpillar for special clutch to provide a slip time of 5-7 sec. applications with additional torque Install a propeller shaft brake to requirements, such as dredges or ships facilitate fast maneuvering (ahead, operating in thick ice. astern, stop). See the Engine Performance section of this guide for a full explanation of the rating curve. Also see the section for Controls.

15 100 100

75 75 Zone Of Limited Operations

50 50

Clutch In Speed Range Percent of Rated Engine Power Percent of Rated Engine Power 25 25

Min. Idle Zone Of Speed Continuous Operation

10 20 30 40 50 60 70 80 90 100 110 Percent of Rated Engine Speed

CURVE #1 (MCR) Figure 10 COMBINATOR CURVE CURVE #3 (CSR)

Controllable Pitch Controllable pitch (CP) propellers are Figure 10 shows the operating range for normally designed at 90 to 100% of the a typical CP propeller installation, see Continuous Service Rating (CSR) at the Engine Performance section for a full rated rpm. See the Engine Performance explanation of the rating curve. The section of this guide. This power level is recommended combinator curve is valid used when the ship is on trial with a for single engine installations. In clean hull at specified speed and draft. installations where several engines are Consider the shaft generators or connected to the same propeller, generators connected to the free end of overload protection or load control is the engine when dimensioning CP necessary. Loads close to the combinator propellers if continuous generator curve are also recommended when all output is used at sea. Overload engines are not operating. The idle protection or load control is (clutch-in) speed will be determined recommended in all installations. separately in each case.

16 Materials and specifications are subject to change without notice.

© 1998 Caterpillar Inc. Printed in U.S.A.