Work_Item_204_T9235-AG-MMC-010_Propulsion_Motor.pdf

T9235-AG-MMC-010

PUBLISHED BY DIRECTION OF COMMANDER MILITARY SEALIFT COMMAND

0910-LP-104-3138

PRELIMINARY

TECHNICAL MANUAL

PROPULSION MOTOR, SYNCHRONOUS, MOTOR

DESIGN M3HSX 305-126/16

FOR

USNS LEWIS AND CLARK (T-AKE 1) CLASS

INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS

(ALSTOM POWER CONVERSION)

ADMIRAL PEARY WAY, PHILADELPHIA, PA

N00024-02-C-2300

DISTRIBUTION STATEMENT A: APPROVED FOR PUBLIC RELEASE; DISTRIBUTION IS UNLIMITED.

n50241

PUBLISHED BY DIRECTION OF COMMANDER MILITARY SEALIFT COMMAND

11 APRIL 2006

0910-LP-104-3138

TECHNICAL MANUAL

PROPULSION MOTOR, SYNCHRONOUS, MOTOR

DESIGN M3HSX 305-126/16

FOR

USNS LEWIS AND CLARK (T-AKE 1) CLASS

INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS

(ALSTOM POWER CONVERSION)

ADMIRAL PEARY WAY, PHILADELPHIA, PA

N00024-02-C-2300

DISTRIBUTION STATEMENT A: APPROVED FOR PUBLIC RELEASE; DISTRIBUTION IS UNLIMITED.

A

List of Effective Pages Date of original pages is:

Original . . . . . . 11 April 2006

Total number of pages in this publication is 248 consisting of the following:

Page No. * Change No. Page No. * Change No.

Cover............................................................... 0 Tech Manual 923A66, page 112

Title/A .............................................................. 0 Dwg D5513302

Tech Manual 923A66, page 1 thru 72 ............ 0 Dwg D5513303

Motor Provisional Parts, 2 pages.................... 0 Dwg D5513304

Tech Manual 923A66, page 73 thru 110 ........ 0 Dwg D5513305

Dwg EZ 95A84700.......................................... 0 Dwg D5513306

Dwg EZ 91S23A66C....................................... 0 Dwg D5513307

Dwg EZ 91S23A66B ....................................... 0 Dwg D5513308

Dwg EZ 91A32600.......................................... 0 Dwg D5513309

Dwg EZ 91A36300.......................................... 0 Dwg D55133010

Dwg EZ 91A31300.......................................... 0 Dwg D55133011

Dwg B5654232................................................ 0 Dwg D55133012

Dwg A5654222................................................ 0 Dwg D55133013

Dwg C5654066 ............................................... 0 Tech Manual 923A66, page 113

Dwg 27106660................................................ 0 Tech Manual 923A66, page 114

Dwg 27106659

Dwg B5654234

Dwg B5654240

Dwg 30246-02 GA

Dwg 30246 FanDet

Dwg C5654302

Tech Manual 923A66, page 111

RENK Bearing I & O Inst, 33 pages

HP Unit Inst Man, 45 pages

DE Bearing PL L747346, 4 pages

NDE Bearing PL L747345, 3 pages

Cooler I,O & M Inst, 15 pages

* Zero in this column indicates an original page

PROPRIETARY INFORMATION OF ALSTOM POWER CONVERSION LTD

Document Ref: 923A66_O&M_rev3 Page 1 of 114 Date: 15/12/05

All Rights Reserved, ©2005 APC Power Conversion Ltd

SYNCHRONOUS PROPULSION MOTOR

INSTALLATION, OPERATION & MAINTENANCE

INSTRUCTION MANUAL

Instruction Book No. 923A66/O&M/rev3

The Synchronous Motors described in this manual were supplied to:

Alstom Power Conversion Inc for NASSCO for T-AKE PM on Order Nos.

MP10035/24823P

MP10054/27263P

Correspondence relating to the machines should quote the ALSTOM Moteurs SA references, which are given on the machine rating plate:

Hull numbers Hull 1 – MUK399670 (471) Hull 2 – MUK399670 (472) Hull 3 – MUK399683 (473)

Serial numbers 923A66-001 923A68-001

933AA4-001

Frame size M36HXS 305 – 126 / 16

This document contains confidential and proprietary information of ALSTOM and must not be used for any purpose other than that for which it is supplied by the Company. It must not be copied or disclosed, wholly or in part, by any person without prior written authority of the Company.

ALSTOM Moteurs SA 4, rue de la Rompure 54250 Champigneulles BP 90 54062 Nancy Cedex

FRANCE

Telephone: +33 (0) 383 38 40 00 Fax: +33 (0) 383 38 42 88

[FOR REPRODUCTION PURPOSES ONLY 5]

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1.2 SAFETY WARNING

Though the instructions and information given in this book are as explicit as is practicable, expertise is still required to install and maintain the machine. If trouble-free service is to be obtained, the machine must be installed correctly, and thereafter maintained in a competent and organised fashion by qualified staff who have been properly trained.

It is strongly recommended that the services of ALSTOM Moteurs’ Customer Support Department staff be employed for the erection and commissioning of the equipment supplied, as they have special knowledge of design details and of suitable erection and checking techniques.

THE HEALTH AND SAFETY AT WORK ACT 1974

The United Kingdom user should comply with the instructions and information in this manual, and is strongly advised that all personnel who will be associated with the equipment supplied under the contract should be made familiar with the information contained in it.

It is essential that the personnel engaged on the installation, commissioning and maintenance of this equipment are both competent and experienced in these fields, and that they comply with the relevant statutory requirements and regulations, including the provisions of the Health & Safety At Work Act, 1974, and any such modifications and amendments which may subsequently become legal requirements.

Users in other countries with corresponding legislation must comply with it. Where there is no legislation, users are strongly recommended to follow a similar code of practice.

[FOR REPRODUCTION PURPOSES ONLY 6]

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1.3 CONTENTS

Section 1 DATA

1.1 Front Sheet

1.2 Safety Warning

1.3 Contents

1.4 Technical Data

Section 2 DESCRIPTION

2.1 General

2.2 Stator

2.3 Rotor

2.4 Bearings

2.5 Cooling System

2.6 Main Terminals

Section 3 STORAGE, INSTALLATION & COMMISSIONING

3.1 Delivery and Preliminary Inspection

3.2 Storage

3.3 Installation

3.4 Location

3.5 Foundations

3.6 Alignment

3.7 Alignment - full procedure

3.8 Insulation Resistance Testing (IR)

3.9 Bearings

3.10 Bearing Insulation

3.11 Earthing and Bonding

3.12 Main Terminals

3.13 Auxiliary Devices and Connections

3.14 Enclosure and Cooling System

3.15 Putting Machine into Service - Checklist

Section 4 OPERATING RECOMMENDATIONS, INSTRUCTIONS AND FAULT-

FINDING

Recommendations

4.1 Operating Recommendations

4.2 Alarm and Trip Settings

4.3 Stator Winding RTDs

4.4 Sealing

Operating instructions

4.5 Starting

4.6 Daily Running Checks

4.7 Shutting Down

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Fault-finding

4.8 Vibration

4.9 Noise

4.10 Winding Overheating - diagnosis

4.11 Bearing Operation

4.12 HP jacking Unit Operation

4.13 Jacking Operation and Control Procedure

4.14 Customer Care

Section 5 ROUTINE MAINTENANCE

5.1 Introduction

5.2 Three Monthly Check (No Dismantling)

5.3 Annual Check

5.4 Cleaning

5.5 Windings

5.6 Air Gap

5.7 Bearings

5.8 Cooler

Section 6 OVERHAUL, INCLUDING WET-CLEANING OF WINDINGS AND

DRYING OUT

6.1 General

6.2 Disconnection

6.3 Main Terminals

6.4 Cooler

6.5 Bearings

6.6 Removal of Rotor

6.7 Cleaning Windings

6.8 Drying out the Insulation

Section 7 REPAIR / REPLACE PROCEDURES

7.0 Provisional parts list

7.1 Precautions

7.2 Replacing the shaft earthing brush

7.3 Replacing the air RTD(s)

7.4 Replacing the water leakage detector

7.5 Replacing the slip ring brushes

7.6 Replacing the heaters

7.7 Removing a heat exchange element

7.8 Replacing the bearing shell RTD

7.9 Replacing the bearing sump RTD

7.10 Removing / Replacing the Tachogenerator

7.11 Removing / Replacing the mains terminal boxes

7.12 Removing / Replacing the upper end covers

7.13 Replacing the enclosure air seal

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Section 8 SPARES, RENEWALS AND APPROVED LUBRICANTS

8.1 General

8.2 Recommended Spares and special tools

8.3 Approved Lubricants

Section 9 DRAWING LIST

Section 10 SUB CONTRACTOR’S LITERATURE

10.1 Bearing – Instructions for Installation and Operation – RENK Bearing

10.2 High Pressure Unit Instruction Manual – Werthenbach Hydraulik

10.3 DE Bearing Spares Part List – RENK – L747346

10.4 NDE Bearing Spare Part List – RENK – L747345

10.5 Cooler – Installation, Operation and Maintenance Instructions – Heat Exchange Industries

Section 11 ILLUSTRATED PARTS BREAKDOWN

11.1 PBS – Sheet 1 D5513302

11.2 PBS – Sheet 2 D5513303

11.3 PBS – Sheet 3 D5513304

11.4 PBS – Sheet 4 D5513305

11.5 PBS – Sheet 5 D5513306

11.6 PBS – Sheet 6 D5513307

11.7 PBS – Sheet 7 D5513308

11.8 PBS – Sheet 8 D5513309

11.9 PBS – Sheet 9 D5513310

11.10 PBS – Sheet 10 D5513311

11.11 PBS – Sheet 11 D5513312

11.12 PBS – Sheet 12 D5513313

Section 12 GLOSSARY OF TERMS

Section 14 MODIFICATION RECORD

[FOR REPRODUCTION PURPOSES ONLY 9]

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1.4 TECHNICAL DATA

GENERAL CHARACTERISTICS

Synchronous Tandem propulsion motor having two stators (each with two three-phase windings with 30° shift) and a single shaft.

Each motor is directly connected to the shaft line and is provided with two pedestal bearings mounted on stools external to the motor frame.

The motors are sized to be driven by 12 pulse type converters.

Motor type synchronous

Motor design M3HXS 305 - 126 / 16

Shaft power 2x11262 kW

Voltage 2 x 1930 V (per stator)

Rated current 2 x 1952 A (per stator)

Power factor 0.90

Rated speed 120 rpm

Frequency 16 Hz

Speed range ± 126 RPM

Number of phases 2 x 3 (per stator)

Service rating Continuous

Connection star / star with 30° shifting

Insulation class F

Temperature rise class B

Maximum ambient temperature 50 °C

Rotor Two rotor cores on a single shaft

Salient poles with damping cage

Motor nominal airgap 8mm

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ELECTRICAL CHARACTERISTICS

Resistances (according to IEC) at 20°c

One stator phase 0.00644 Ω

Rotor 0.74 Ω

Reactances non saturated

Direct-axis synchronous XD 324 %

Direct-axis transient X’D 61.7 %

Direct-axis subtransient X’’D 29.7 %

Quadrature-axis subtransient X’’Q 27.2 %

Negative sequence X2 29.8 %

Time constants

Transient short-circuit T’D 1.19 s

Armature dc time constant Ta 0.219 s

Subtransient short-circuit T’’D 0.043 s

Quadrature-axis subtransient short-circuit T’’Q 0.054 s

Maximum stator temperature (by resistance variation) 120 °C

Maximum rotor temperature (by resistance variation) 120 °C

Rotor

Rated field current at full load 344 A

Rated field voltage at full load 358 V

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D.E. BEARING

Refer to drawing: 27106660

Bearing supplier: Renk

Type: SCWFK 71-630 K

Self-lubricated with oil disc and water cooled

Bearing insulated at spherical seating

CHARACTERISTICS

Shaft dia 630 mm

Rated speed 120 rpm

Journal load 613 kN

Journal surface 245700 mm2

Journal pressure 2.49 N/mm2

Mean diametric clearance 0.666 mm

Power losses 4.2 kW

Oil grade ISO VG 150

Water flow rate 26 litres/min

H.P. jacking oil flow 1.2 litres/min

Oil quantity 184 litres

Weight 2200 kg

Refer to RENK BEARING instruction manual for more technical information.

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N.D.E. BEARING

Refer to drawing: 27106659

Bearing supplier: Renk

Type: SCWFQ 63-600 K

Self-lubricated with oil disc and water cooled

Bearing insulated at spherical seating

CHARACTERISTICS

Shaft dia 600 mm

Rated speed 120 rpm

Journal load 394 kN

Journal surface 207000 mm2

Journal pressure 1.9 N/mm2

Mean diametric clearance 0.666 mm

Power losses 3.2 kW

Oil grade ISO VG 150

Water flow rate 26 litres/min

H.P. jacking oil flow 1.2 litres/min

Oil quantity 102 litres

Weight 1750 kg

Refer to RENK BEARING instruction manual for more technical information

[FOR REPRODUCTION PURPOSES ONLY 13]

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COOLING

Refer to drawing 30246-02 GA

The motor power losses are evacuated by forced ventilation in closed circuit with two air coolers and four separate fans direct driven by electric motors on each stator.

The coolers are mounted on the top of the motor, to allow removal without dismantling the motor frame

The coolers are of double tube type

Characteristics for one air cooler

Losses to be dissipated 223 kW

Air flow rate 8.4 m3 / s

Air inlet temperature 71.5 °C

Air outlet temperature 47 °C

Water flow rate 18.9 litres/sec

Water inlet temperature 39 °C

Water outlet temperature 41.8 °C

Water pressure drop 30 kPa

Service pressure 6.9 bar

Test pressure 10.35 bar

Water capacity 53 litres

Weight empty 1160 kg

FAN MOTORS

Refer to drawing 30246 FanDet

The cooling air circulation is boosted by four separate motor-fans units, fitted on the heat exchanger attached on the motor frame.

Motor characteristics :

Type LS 132M B5 Aluminium frame

Power 11 kW

Speed 1800 rpm

Voltage 460 V 3 phases

Frequency 60 Hz

Service rating Continuous

Enclosure IP56

Marine classification ABS

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HYDROSTATIC JACKING UNIT

Refer to supplier documentation (01-264-T-AKE-HP-unit-WB)

Each bearing is provided with a hydrostatic jacking unit. The hydrostatic jacking unit provides a flow of oil to establish a minimal oil film thickness before motor starting and during low speed rotation. Each unit includes two motors: one for normal running, and one for safety.

Characteristics of the motors:

Motor type ADDA BG90S – ‘ABS’

Supplier Werthenbach Hydraulik

Power 1.3 kW

Speed 1700 rpm

Voltage 460 V 3 phases

Frequency 60 Hz

Current 2.75 A

Power factor 0.75

Max ambient temperature 50°C

Temperature rise class F

Service rating Continuous

Enclosure IP56

Marine classification ABS

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HYDROSTATIC JACKING UNIT SETTINGS

These settings are based on Alstom Moteurs’ recommendations about the Operating and Control procedure of the Jacking Units.

Pressure levels :

§ P = stabilised pressure on board.

§ P1 : 85% of (P - 20 bars) = rated pressure level. Down switch.

§ P2 : 50% of (P - 20 bars) = low/lack of pressure level. Down switch.

§ P3 : 70% of (P - 20 bars) = intermediate pressure level to start safety pump. Down switch.

§ P4 : 125% of P = lift pressure peak level = test of rotor lift. Up switch.

§ Safety valve = 170 bars, then if overpressure, oil goes into bearing oil bath.

§ For example, if P = 60 bars, P - 20 bars=40 bars, then P1=35 bars, P2=20 bars, P3=30 bars, P4=75bars.

§ Remark : There are four 4-20mA transmitters per HP unit (so no switches).

Oil flow levels and Clogging indicator :

§ F1 : 1.0 l/min = 80% of rated oil flow level. Up switch.

§ F2 : Not set as such but is the falling pressure switching from the F1 setting point (for low/lack of oil flow level). Down switch.

§ Clogging switch indicates if filter blocked.

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TEMPERATURE DETECTORS FOR STATOR WINDING

Type Pt100 SIMPLEX 4 wire Supplier SENSING DEVICES LTD.

Probe Pt 100 – 4 wires with Pt100 element of accuracy class type B, according to BS EN 60 751: 1996

OVERVOLTAGE PROTECTION UNITS FOR STATOR WINDING DETECTORS

Type TERMITRAB modular terminal bloc SLKK5 / 24VDC Supplier PHOENIX CONTACT Quantity 80 total (40 per stator) located in the auxiliary terminal boxes

AIR TEMPERATURE PROBES

4 Probes located in the cold air circuit of each stator Type Simplex Pt 100 3 wire Supplier THERMOCOUPLE INSTRUMENTS LTD.

BEARING TEMPERATURE PROBE

Two probes per bearing for shell temperature Type Double platinum resistance 100 ohm at 0°C ( 6 wires ) Supplier JUNEMANN

OIL BEARING TEMPERATURE PROBE

Two probes per bearing for oil sump temperature Type Double platinum resistance 100 ohm at 0°C ( 6 wires ) Supplier JUNEMANN

BEARING LEVEL SWITCH

Optical level switch

2 Optical level switches per bearing Type CLD2001EM Supplier KONTROLLELEKTRONIK

Level switch relay

2 relay outputs per unit mounted in auxiliary terminal box Type CLD2000 Supplier KONTROLLELEKTRONIK

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WATER LEAKAGE DETECTORS

Each cooler is supplied with two leakage detectors which means a total of eight devices.

Leak detectors are connected to a pipe, which collects the water leaks coming from the interspace between double tube-plates. Each leakage detector has an overflow pipe, which gives a visual indication of leakage.

Supplier KUBLER Type KSR 502-ABAU-GL Contacts Single change-over contact

SPACE HEATERS

Six space heaters are located inside each motor frame.

Supplier LOVAL Reference Type BLE 1 - 500W Power 500 W Voltage 120 V – single phase – 60 Hz

DC TACHOGENERATOR

Refer to drawing C5654302 included in section 9.

The DC tachogenerator is mounted on the Non Driving End of the shaft.

Type 115 TG 100 44 100V/1000RPM Manufacturer CONTROL TECHNIQUES

NEUTRAL RESISTORS

The neutral resistors are not supplied by Alstom Moteurs therefore no details appear in this manual.

They are mounted remote to the motors.

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MASS AND INERTIA

APPROXIMATE MASS ( kg )

Rotor complete 86000

Wound stator 50000

Motor frame 35000

Endshields (2 off) 4000

Bearings (2 off) 3950

Bearing supports (2 off) 17000

Mains terminal boxes (4 off) 4000

Heat exchangers (4 off) 5000

Miscellaneous 5050

TOTAL MOTOR WEIGHT 210000

APPROXIMATE INERTIA ( kgm2)

Rotor inertia 65129

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NAME PLATE

IDENTIFICATION NUMBER :

§ 923A66-001 § 923A68-001

§ 933AA4-001

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SECTION 2 – DESCRIPTION

2.1 GENERAL

These machines have been designed for mounting in a ship. Although they have some special features they employ standard constructions where possible and have no features which might require skills beyond those normally available on a ship.

The propulsion electric motor is directly connected to the shaft line through its flanged shaft end.

The motor is provided with two pedestal bearings mounted on integral stools external to the motor housing for an easier access. Neither of these bearings is a thrust bearing however the DE bearing is rated for uncoupled running only.

The Propulsion motor is a tandem configuration with two independent stators each having two three-phase windings with 30° electrical shift and sized to be driven by synchroconverters from zero speed to maximum speed in both directions of rotation.

All the items making up the machine are mounted on the fabricated steel frame, which is the main structural member. It carries the corepacks, the stools on which the bearings and the jacking pump units are fitted, the cooler and the terminals.

Alignment of the various components is achieved in the factory by accurate machining of all the mating surfaces, and the provision of dowels or spigots where necessary.

This alignment is intended to last for the life of the machine, and no means of adjustment is provided.

The frame has mounting feet with provision for bolting and doweling to the structure on which the machine is to be mounted.

2.2 STATOR

The motor frame is made in two halves to aid manufacture. These are bolted together to form the tandem arrangement. Each frame supports a stator, a bearing stool (onto which the bearings and the rotor are supported), the upper covers, the main and auxiliary terminal boxes and the heat exchangers.

Lifting points on top of each frame allow the whole motor to be lifted and transported in a single piece.

Each stator core is built on a mandrel, clamped between two substantial endplates, and welded together while still under compression with core bars along the outer surface of the laminations. These core bars extend beyond the endplates at both ends, and the extensions form part of the winding overhang bracing system.

Each half-frame is a fabricated steel construction with internal sections to give strength and rigidity. It is the main structural member and all components are mounted off it.

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The core is inserted into a frame in the correct axial and radial alignment. The stator is then wound.

Each stator winding has two separate three phase system having an electrical angle of 30° which allows a running at “half motor” configuration in case of emergency.

Each three-phase winding is star connected with the star point connected to a neutral resistor located remotely to the machine.

The stator coils are formed from annealed copper strip insulated with film-backed mica-paper tape first by forming loops of the correct number of turns, followed by bonding of the coil’s straight portion and then by pulling the loop to the correct shape. The coils are then insulated with further mica rich materials and the overhangs finished with sealing tape.

The coils are inserted into the stator slots and wedged along the length of the corepack. The coil overhangs have packing blocks fitted between each coil side and are braced to the core bar extensions. Inter-coil connections are formed by brazed joints and then insulated.

The wound core is finally impregnated with an epoxy-based resin. The two fully wound frames are then bolted together.

Several electrical tests are carried out at each stage of the manufacturing process in order to guarantee the most efficient quality. Many of these are witnessed by the classification society.

2.3 ROTOR

The rotor consists of: the shaft, two rotor rims each with a set of poles and two sets of connecting ring.

The rotor is axially free and allows the thermal expansion of the shaft line from the motor up to the propeller thrust bearing

The shaft is made of forged steel and the rims of GS cast iron. The materials are selected in accordance with the rules of the Classification Society. Both the shaft and the rims are machined on CNC machining centre with a high accurate precision, and after, the rims are mounted on the shaft and doweled in position.

The poles are bolted to the rotor rims which allows mounting-dismantling in case of maintenance. In this case, field coils can be also dismantled for maintenance, if required. The pole shoes are in thin laminated steel pressed between two end plates and are secured by rivets. The field coil windings are carefully located and secured to the pole body. They are supported by the pole shoe.

The conductor of the field coil is of flat high conductivity copper strip.

The insulation between the turns is by epoxy –resin pre-impregnated class F materials.

The pole winding is hot pressed. The connection between the field coil windings and the connections to the collector rings are carefully secured by clamps. The rotor is

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All Rights Reserved, ©2005 APC Power Conversion Ltd equipped with a copper damper winding in form of cage located around the upper part of poles.

DC excitation for the motor rotor field is supplied via slip rings in the collector assembly. A set of slip rings is supplied at each end of the motor.

2.4 BEARINGS

The bearings are mounted in a short pedestal housing which is attached to an extended stool mounted from each end of the motor frame by a bolted joint. Doweling is provided to ensure accurate alignment is maintained between each of the parts.

The housing is split on the horizontal centreline, which allows the bearing to be dismantled and inspected without disturbing the alignment.

Each liner is lined with white metal, and has a spherical seat which fits into the housing. The contact areas in the housing of the DE and NDE bearings are lined with a hard insulating finish, which provides the bearing insulation. The insulation is shorted at the DE and in addition an earth brush is fitted to ensure the shaft is earthed at all times to prevent the circulation of damaging currents.

The spherical seating is provided to aid final alignment when the machine is assembled or re-assembled; when the top half of the housing is bolted up, the liner is locked, and it is not designed to move in service. The DE bearing contains thrust pads, suitable only for limiting rotor end float when the motor is uncoupled.

Oil for lubrication is contained in the lower part of the bearing housing, and is taken to the bearing by fixed oil discs mounted on the shaft.

Labyrinth seals and flingers on both sides of the bearings ensure no oil leaves the bearing and no external contamination can enter the bearing.

Each bearing is supplied with connections to the hydrostatic jacking unit:

• One connection for HP pump suction

• One connection for HP supply

• One connection for the pressure relief valve

The internal connections for the HP oil are insulated flexible pipes so not to bridge the bearing insulation. This unit will provide high-pressure oil beneath the shaft to ensure the formation of an oil film at low speeds.

Each bearing contains a water cooler and thermostatically controlled heater to ensure the oil is maintained at the correct operating temperature. The jacking pump oil circuit is protected by a duplex filter arrangement mounted on the HP jacking unit.

2.5 COOLING SYSTEM

The machine losses ( joules, iron, mechanical,…) are removed out of the housing to the air cooler by air circulating in the machine provided by separate motor-fans units fitted in the heat exchanger.

The ventilation in each stator is forced in closed circuit with two double-tube air-water heat exchanger and four separate motor-driven fans.

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Cooler materials are in accordance with the requirements of the Classification Society and are suitable for both sea water and fresh water.

The air cools the machine by circulating :

• Around the stator coil endwindings

• Around the rotor coils

• In the air gap

• In the cooling ducts of the stator

The air is then exhausted out of the stator core and is cooled by the air-water exchanger.

2.6 MAIN TERMINALS

There is one main terminal box per stator winding i.e. four in total. Two are mounted on each end of the motor frame. The terminal box is a steel enclosure that forms part of the DE upper endbracket. The main machine terminals are copper busbars drilled to accept customer’s incoming cables. There are 4 terminals per terminal box three phase connections and a neutral point connection.

Details of how the phases are connected are given on the wiring diagram.

The terminal box provides a chamber to protect the customer’s cable connections and provides a cable gland plate through which customers cables can enter the box.

Removable covers allow access to the connections.

The terminal box arrangement is split on the vertical centre line to allow access for a lifting point for the bearings.

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SECTION 3 - STORAGE, INSTALLATION AND COMMISSIONING

3.1 DELIVERY AND PRELIMINARY INSPECTION

The motor will be delivered to site unpacked but protected from the weather by tarpaulins and is suitable only for delivery into a covered storage area or for direct placement on the foundations. Lifting points on the top of the machine frame are provided. The weight of the machine only, will be given on the machine nameplate and the outline drawing. The weight of the machine together with any baseplate, shipping base or packing will be found on the shipping documents.

WARNINGS:

1. SUITABLE LIFTING EQUIPMENT MUST BE AVAILABLE:

- A CRANE OF ADEQUATE LIFTING CAPACITY AND HEIGHT.

- SLINGS WHERE NECESSARY WHICH ARE LONG ENOUGH AND IN GOOD ORDER.

- HOOKS AND CHAINS WHERE NECESSARY WHICH ARE IN GOOD ORDER.

WHEN IT HAS BEEN UNLOADED ON THE SITE, THE MACHINE SHOULD BE CAREFULLY

EXAMINED. IF PARTS ARE DAMAGED OR MISSING, THE CARRIERS AND ALSTOM MOTEURS

SHOULD BE INFORMED WITHIN THREE DAYS OF DELIVERY. IF GOODS SENT OVERSEAS

ARE RECEIVED DAMAGED FROM ANY CAUSE WHATSOEVER, ANY COMMUNICATION

ADDRESSED EITHER TO THE INSURANCE COMPANY OR TO ALSTOM MOTEURS SHOULD BE

ACCOMPANIED BY A CERTIFICATE OF EXAMINATION FROM THE NEAREST LLOYD'S

SURVEYOR, TOGETHER WITH PHOTOGRAPHIC OR OTHER USEFUL EVIDENCE.

3.2 STORAGE

Take the following precautions for the storage:

• Store in a dry place away from dust and bad weather.

• Avoid temperature variations, as they might cause condensation.

• Store on a floor which is free from vibrations, as they might deteriorate the bearing. Otherwise, take the necessary precautions in order to avoid the transmitting of these vibrations to the machine: for instance use rubber wedges

• For machines fitted with space heaters: start the heating in order to keep the inside air temperature 2 to 3°C higher than the outside temperature, thus avoiding potential condensations.

• Bearings: Refer to bearing maintenance sheet.

• Check that the unpainted machined parts have a protective coating (rust preventive varnish) that can be easily removed.

Note: When different storage conditions have been defined in the contract, these conditions take precedence over those given above.

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If the storage conditions are severe, or the storage period is likely to exceed 6 months, then more rigorous precautions should be taken, and ALSTOM Moteurs should be consulted.

3.2.1 MAINTENANCE OF THE BEARINGS DURING STORAGE

Transport protection :

Carry out the corrosion protection and apply enough lubricant on the running surfaces of the bearing.

Corrosion protection for longer standstill periods

If you want to protect the bearing mounted on an installation against corrosion, proceed as follows:

Dismantle the bearing.

Clean the bearing.

Paint or spray the top half of the shell, the bottom half of the shell and the shaft with Tectyl 511 M Assemble the bearing.

Close all connection holes with screw plugs.

Seal the shaft between: - shaft seal and housing

- shaft seal and shaft by using a self-adhesive, permanent tape.

Remove the top sight glass. Spray some anti corrosive such as TECTYL 511 M into the bearing.

Put a bag of desiccant (silicate gel) inside. The desiccant absorbs the humidity and prevents the formation of condensation water into the bearing.

Close the bearing tight with the top sight glass.

In case the standstill period is longer than ½ year :

Repeat the preservation procedures.

Put a new bag of desiccant into the bearing.

Cleaning and checking of the bearing :

Use non aggressive detergents such as for instance:

Valvoline 150 Alkaline cleaning compounds (pH-value 6 to 9, short reaction time)

WARNING: PLEASE OBSERVE THE INSTRUCTIONS FOR THE USE OF DETERGENTS. NEVER USE

CLEANING WOOL OR CLOTH. RESIDUES OF SUCH MATERIALS LEFT IN THE

BEARING COULD DAMAGE THE BEARING AND LEAD TO EXCESSIVE

TEMPERATURES.

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3.3 INSTALLATION

It is expected a machine of this size will be erected and commissioned only by experienced personnel, and the following instructions are merely intended as a guide to some of the more important aspects.

Refer to:

Outline drawing: EZ 95S A847 00 Motor lifting and handling drawing: EZ 91S23A66B

WARNING: INSTALLATION WILL OFTEN INVOLVE LIFTING THE MACHINE, AND THE

FOLLOWING POINTS MUST BE OBSERVED:

(a) Lifting lugs on components such as coolers are only for lifting the component and must not be used to lift the whole machine.

(b) When the machine is mounted with the driven equipment on a common base, the lifting lugs on the machine must not be used to lift the whole assembly.

(c) The force on lugs must be applied in the designed direction.

(d) All slings and lifting equipment must be adequate and suitable for the job in hand.

In particular, crane control must be smooth, to avoid shock loads and consequent stresses.

WARNING: A ROTOR LOCKING SYSTEM IS PROVIDED FOR HANDLING AND

TRANSPORTATION - NEVER HANDLE THE MOTOR WHEN THE SHAFT LOCK IS

NOT IN POSITION

3.3.1 ROTOR LOCKING DEVICE

The rotor is locked in place by a device including:

• an axial-locking system at the Non Driving End, which locks the shaft in the right axial position.

• a D.E. locking strap which avoid shaft radial movement during transportation.

WARNING: DO NOT REMOVE THE SHAFT LOCKING DEVICE BEFORE INSTALLATION AND

ALIGNMENT OF THE MOTOR

When propulsion motor is delivered to Shipyard, at the NDE is fixed a “locking cross” The function of this device is to block the rotor during motor transportation to Shipyard. The rotor is blocked axially and prevented from rotating to prevent bearing damage.

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We advise to keep this rotor blocking tool on board in Machinery room near the propulsion motor as it could be useful for Shipyard and Ship Owner for shaftline work:

• For coupling alignment of the motor flange with the shaftline. The rotor blocking tool keeps the rotor in axial position while the propulsion motor is inclined with shaftline slope (note also that as rotor blocking tool is fixed at NDE, then motor flange is completely free for coupling work).

• For maintenance of shaftline (or for whatever reason), if motor is uncoupled, to keep the rotor in position due to the shaftline inclination.

• In order to fit the rotor blocking tool then dismantle the DC tacho-generators at NDE to gain access to the forward rotor shaft extremity. Threaded rods can then be fitted to the shaft and the rotor blocking tool fitted/adjusted with nuts attached to these rods. The rotor can be blocked in the centre of the axial clearance i.e.

without any displacement (could be ±10 mm max if not using the rotor blocking tool). The main advantage of fitting the rotor blocking tool is using this tool to move the rotor forward if it is necessary to create clearance between the motor flange and the shaftline flange (to facilitate shaftline alignment work, or assembly/dismantling of part of the shaftline coupled to motor). Note the bearings’ jacking units must be operating to avoid bearing whitemetal damage.

As 10 mm is a maximum theoretical, we advise not to exceed ± 5 mm rotor longitudinal movement compared to the delivered rotor position.

3.4 LOCATION

Please bear in mind the following points when choosing a location for the machine:

(a) Unless previously specified, the location should be dry, well-ventilated and free from dust and dirt. Acid fumes and other corrosive agents should be excluded.

(b) The location should allow sufficient space around the machine for routine maintenance to be done, and should allow adequate withdrawal distance for the cooler stacks, bearing shells etc.

(c) The location should permit the use of lifting equipment, both to assist in erecting the machine and also in case it has to be dismantled or removed at some future time.

3.5 FOUNDATIONS

MACHINE MOUNTED DIRECT TO SHIP HULL

All the information necessary for deciding on the Hull design is given on the machine Outline Drawing. The deck seating is designed by the Shipyard. These operations are defined and realised by the yard.

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The motors are delivered fully assembled and the motor adjustments have already been made in factory. (motor and exciter air gap, bearing adjustments,….). After adjustment, the holes in the motor frame are counter-drilled with the bearings and fitted bolts put in place to secure the rotor, bearings and stator adjustments.

For transportation the rotor is locked in position with a system that prevents from any axial movement, as shown in previous pages. So it is well located and ready for mounting and alignment with the shaft line. Caution: a change in these adjustments is not recommended and can even damage the motor if performed by a non-specialist.

During installation on the hull base plate the alignment is realised with the shaft line by displacement of the whole motor. The machine can be levelled using levelling plates, chocking plates or shims. Usually a combination of these is used. Fine adjustment is carried out with shims using the vertical jacking screws to lift the machine. Loads on jacking screws should be measured in order to check that propulsion motor frame is not twisted or bent while motor chocking.

When final alignment of the machine is satisfactory the machine must be fixed in position to prevent any movement which will affect this alignment. Dowels, fitted bolts, chocking blocks/stops or a combination of these can fix the machine. The dowels/blocks must be fixed to a part of the hull suitably rated for the forces associated with shock and the dynamic movements of the vessel.

The fixation on the hull frame is indicated on the Outline drawing – EZ 95 A847 00.

Do not remove the rotor locking device before the coupling operation with the whole shaft line.

3.6 ALIGNMENT

This machine is mounted directly onto the ship hull. When it is first installed, the full alignment procedure given in Para. 3.7 must be followed, but if the machine is subsequently removed for any reason, a shorter procedure may be followed when it is replaced.

Provided that final alignment dowels or fitted bolts have been used and all the bolts/dowels and shims are clearly labelled, the machine may be re-assembled on its mounting structure without the full alignment checks being made, but if there is any doubt, the full alignment procedure must be followed.

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3.7 ALIGNMENT - FULL PROCEDURE

Coupling Up Machine with two plain bearings, both with end float, and Solidly Coupled

WARNING: BEFORE STARTING WORK, ENSURE ALL ELECTRICAL CIRCUITS TO THE MACHINE

ARE SWITCHED OFF, WITH ISOLATORS/CIRCUIT BREAKERS LOCKED IN THE

OPEN (OFF) POSITION. REMOVE ALL FUSES FROM AUXILIARY SUPPLIES AND

GROUND THE MV WINDINGS.

1. Ensure the machine frame is set level and set up in the correct axial positions to give equal clearances between shaft shoulders and liner ends of the bearing. There is a shaft position indicator on the outer end of the DE bearing. The middle line of the indicator block should coincide with the inboard edge of the shaft groove to achieve this condition (see Figure 3.7.2 Typical End Float Indicator).

2. Temporarily bolt down the machine in accordance with the Outline Drawing and the installer's master foundation drawing, shimming as necessary to get good 'by eye' alignment of the shafts.

3. Align the machine in line with the following instructions. Temperature differences and centre heights need consideration. Where the shafts of two pieces of equipment operating at different temperatures are coupled together, it may be necessary to make an allowance for differential thermal growth of the height of centres.

The allowance to be made for ferrous materials is 0.1mm per metre of centre height per 10oC temperature difference, the hotter equipment to be set lower when alignment is carried out cold.

4. Remove the rotor blocking device.

5. Final tests for alignment should preferably be carried out with the equipment at normal running temperature.

6. Secure the machine in accordance with the outline arrangement drawing provided by ALSTOM and the driven equipment maker's instructions.

Alignment

To achieve optimum running quality, the alignment of the machine and driven equipment must be as near perfect as possible. The main types of misalignment are:

(a) Parallel. The axes of the driving and driven shafts are parallel but laterally displaced.

(b) Angular. The axes of the two shafts are not parallel, but cross each other.

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(c) Axial. The machine shaft is not in its correct axial position in the bearing. This type of mismatch is not as critical as type (a) and (b).

The limits of misalignment given in the following alignment procedure are intended as a guide.

1. Parallel Alignment (Figure 3.7.1A Checking Parallel Alignment or Displacement)

With an externally mounted dial-gauge, each half coupling should be checked separately for concentricity; any out-of-truth should be related to shaft position and recorded.

The radial displacement of one shaft relative to the other is usually measured by fixing a dial-gauge to one half coupling to register on a suitable external diameter of the other half coupling. The two shafts are then rotated together connected by a loose pin, and the gauge readings noted after each quarter of a turn.

The parallel alignment must be correct to within + 0.025mm, i.e. the total indicated reading must not exceed 0.05mm.

2. Angular Alignment (Figure 3.7.1B Checking Angular Alignment)

In principle this is checked by measuring the axial 'gaps' at the periphery of the half couplings. In practice an arrangement using a dial-gauge, as shown, is often found most convenient. The procedure for this is as follows:

The coupling halves should be match marked at the 12 o'clock position and the gap-dimension between the coupling faces measured at the 12, 3, 6 and 9 o'clock positions. Turn the coupling halves together until the match marks are at the 3 o'clock position, and take the measurements again. Repeat this process with the match marks at the 6 and 9 o'clock positions. Average the four readings taken at the top vertical centre line (12 o'clock position). Similarly, average the four readings at each of the other positions.

The difference between the top and bottom readings on the vertical centre line (i.e.

the difference between average readings at the 12 o'clock position and the 6 o'clock position) gives a value which is twice the vertical misalignment; and the difference between the horizontal readings (i.e. between 3 and 9 o'clock positions) gives twice the horizontal misalignment.

The angular alignment must be adjusted until the result conforms with the following requirements. For couplings up to and including 400mm diameter, the difference between opposite readings must not exceed 0.17mm per metre of coupling diameter. For couplings greater than 400mm diameter the limit of acceptability is 0.13mm per metre of coupling diameter.

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3. Axial Alignment

The relative axial positions of the two halves of the coupling are specified by the machine bearings and any axial constraints in the driven equipment (thrust bearing, gearbox etc.). The two shafts should be set to give the correct clearances in both items as a first step in the alignment procedure and re-checked as alignment proceeds.

At the same time the axial position of the machine should be adjusted to give correct axial clearances in the machine bearings, as shown on the general arrangement drawing. Although the bearings have white metal faces, these are not for constant or significant loaded use.

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For detecting this type of misalignment

A. Checking parallel alignment or displacement

For detecting this type of misalignment

B. Checking angular alignment

FIGURE 3.7.1 CHECKING SHAFT ALIGNMENT

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FIGURE 3.7.2 TYPICAL END FLOAT INDICATOR

Saw cuts to correspond with edge of groove in shaft

Endfloat indicator block

Bearing seal

Shaft

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3.8 INSULATION RESISTANCE TESTING (IR)

Insulation resistance tests are made when a machine is first installed, and thereafter at intervals throughout its life. This section is written to cover all cases, and inappropriate parts should be disregarded.

Insulation tests are normally made using a dc tester or "Megger". Such testers are either battery-powered electronic or turned by hand. If polarisation index (PI) tests are to be made on the stator windings, the voltage must be applied for 10 minutes, so hand-turning is not practicable and either a motorised or electronic tester must be used.

Note: The batteries in an electronic tester will be exhausted after one 10 minute test.

Preferred d.c. test voltages

COMPONENT D.C. TEST VOLTAGE

Stators (F3 insulation) 1000V* Bearing insulation 100V

* For the first test of a winding in these categories, a 500V tester should be used, before proceeding to test at the higher voltage.

For a machine that has been in service, the results are affected by the general condition of the surface of the windings as well as by the leakage through the main insulation.

Interpretation of the results can be difficult if contamination is present. For this reason, if the result of the IR test is unsatisfactory, the surfaces of the windings should be examined to make sure that they are clean and dry, and not contaminated by moisture, oil, salt, carbon dust or other foreign matter. If contamination is present, it should be cleaned off;

see Paras 6.7 and 6.8.

WARNINGS AND CAUTIONS:

1. BEFORE ATTEMPTING ANY INSULATION RESISTANCE TEST IT IS ESSENTIAL TO EARTH

THE FRAME OF THE MACHINE AND ANY SECTIONS OF THE WINDINGS NOT BEING

TESTED.

2. DRY INSULATION WITH A HIGH INSULATION RESISTANCE IS CAPABLE OF HOLDING

AN ELECTRICAL CHARGE FOR SEVERAL HOURS AFTER THE REMOVAL OF THE APPLIED

VOLTAGE, SO FOR REASONS OF BOTH SAFETY AND ACCURACY IT IS ESSENTIAL THE

WINDING, OR SECTION UNDER TEST, IS ADEQUATELY EARTHED BOTH BEFORE AND

AFTER THE APPLICATION OF THE TEST POTENTIAL. STATOR WINDINGS RATED UP TO

10MW OR 10MVA SHOULD BE EARTHED FOR NOT LESS THAN 15 MINUTES. FOR

LARGER STATORS A PERIOD OF 30 MINUTES SHOULD BE ALLOWED.

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Stator IR tests

The tests may be carried out without disconnecting the supply cables but, if an unsatisfactory result is obtained, then the winding should be isolated from all external cables and connections before repeating the test.

The insulation resistance of the complete winding and of each individual phase, with the remaining phases earthed, should be measured. The insulation resistance (Rph) of one phase to earth on a 3-phase winding is approximately twice that of the complete winding (Rw), therefore the measured value must be divided by two to obtain a value for comparison with the value Rw recommended in the next paragraph. Where it is not practicable to separate the phases, then the test can only be carried out on the complete winding and the measured value compared directly with Rw.

Each test is carried out by connecting the high-voltage lead of the d.c. tester to the conductor or terminal of the winding (or phase) under test and the other (earth) lead to the frame. The instrument is then switched on and the test voltage maintained for one minute at which stage the insulation resistance reading R1 is noted. Except on machines having a line voltage less than 750V the test is continued and an additional reading (R10) taken after 10 minutes. The two values R1 and R10 are used to calculate the polarisation index.

Recommended Minimum Value of Insulation Resistance

Insulation resistance varies considerably for different insulation systems, machine sizes, operating voltages and atmospheric conditions but for practical purposes a recommended minimum value, Rw, for the complete winding can be calculated from the following formula:

Rw = Pt(kV + 1) Megohms where: Pt is a factor dependent on the condition of the winding and on the ambient temperature at which the test is carried out, and kV = Line voltage in kilovolts.

Values of Pt are shown on Figure 3.8.1 (Pt Factor Against Winding Temperature For Three Conditions Of The Winding), for the following basic conditions:

(a) New machine with dry and uncontaminated insulation.

(b) Machine after a period of service running with dry and clean (uncontaminated) insulation.

(c) Machine after service ageing with dry but dirty (normal industrial contamination) insulation.

The value of Pt used must be decided by considering the age and amount of contamination on the machine end windings. Condition (a) should be adhered to for all

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On machines with line voltages up to 750V the insulation resistance can be considered satisfactory provided it is greater than the minimum specified above. In general, on higher voltage machines (i.e. > 750V) both the value of the insulation resistance and the polarisation index must be greater than the minima specified. If either is not, a dry-out must be carried out.

Polarisation Index

The measured insulation resistance of a winding normally increases with the time of application of the d.c. test voltage.