HJ241 Product Manual.pdf

HJ241

HJ241 Product Manual

R4A2

Jet unit Manual

Copyright © 2018 C.W.F. Hamilton Ltd All rights reserved. No part of this document may be reproduced, stored in a retrieval system or transmitted in any form or by any means; electronic, electrostatic, magnetic tape, mechanical, photocopying, recording or otherwise, without permission in writing from C.W.F. Hamilton & Co Ltd.

Due to our policy of continuous development, specifications in this document are subject to change without notice or obligation.

Jet Model HJ241 Part number 089241 Revision R4 25/07/17 Amendment A2 08/02/18 i

Contents

1 - Introduction _______________________________________________________ 1-1

Limited warranty _________________________________________________________ 1-1

Warranty and ownership registration form ____________________________________ 1-3

General safety notice ______________________________________________________ 1-4

Symbols_________________________________________________________________ 1-5

2 - Product Description ______________________________________________ 2-1

Introduction _____________________________________________________________ 2-1

Equipment description _____________________________________________________ 2-2

Main components ___________________________________________________ 2-3

3 - Design Basics ______________________________________________________ 3-1

Propulsion system design __________________________________________________ 3-1

Hull loads __________________________________________________________ 3-1

Hull design ______________________________________________________________ 3-4

Mono hulled vessel __________________________________________________ 3-4

Multi hulled vessels _________________________________________________ 3-5

Trim tabs __________________________________________________________ 3-5

Drive lines _______________________________________________________________ 3-7

Requirements of the driveline _________________________________________ 3-7

Engineering checks __________________________________________________ 3-7

Driveline options ____________________________________________________ 3-7

Misalignment absorbing coupling ______________________________________ 3-8

Long drive shafts ____________________________________________________ 3-9

Universal driveshaft alignment _____________________________________________ 3-10

Jet coupling flange details ___________________________________________ 3-11

Moments of inertia _________________________________________________ 3-11

Mainshaft dimensions ______________________________________________ 3-11

Critical speed of mainshaft ___________________________________________ 3-11 ii

Jet mainshaft alignment ___________________________________________________ 3-12

Water offtake ___________________________________________________________ 3-13

Conventional water pickup ___________________________________________ 3-13

Engine location and mounting ______________________________________________ 3-14

General __________________________________________________________ 3-14

Engine mounting ___________________________________________________ 3-14

Engine systems ____________________________________________________ 3-14

Exhaust systems ___________________________________________________ 3-14

Governor settings __________________________________________________ 3-15

Dry run kit (optional extra) ________________________________________________ 3-16

Scope of use ______________________________________________________ 3-16

4 - Precautions Against Corrosion _________________________________ 4-1

General _________________________________________________________________ 4-1

Electrical wiring system ______________________________________________ 4-1

D.C. systems _______________________________________________________ 4-2

A.C. Systems _______________________________________________________ 4-2

Shore connections ________________________________________________________ 4-2

Using an isolating transformer _________________________________________ 4-2

Using a galvanic isolator ______________________________________________ 4-3

Earth bonding system _____________________________________________________ 4-3

Corrosion monitor ________________________________________________________ 4-4

Trim tabs and other submerged fittings _______________________________________ 4-4

Earth connections for electronic equipment ___________________________________ 4-4

Anodes _________________________________________________________________ 4-5

Hull anodes ________________________________________________________ 4-5

Anti-fouling paint _________________________________________________________ 4-5

Anti-seize compound ______________________________________________________ 4-5

Impressed current protection _______________________________________________ 4-6

Steel hulls and carbon fibre reinforced F.R.P. hulls ______________________________ 4-6

Earth bonding system (not normally current conducting) ___________________ 4-6

Checking the insulation ______________________________________________ 4-6 iii

5 - Installation _________________________________________________________ 5-1

General _________________________________________________________________ 5-1

Installation drawings ______________________________________________________ 5-2

Installing the intake block __________________________________________________ 5-2

Hull preparation ____________________________________________________ 5-2

GRP hull intake block ________________________________________________ 5-3

Aluminium hull intake block ___________________________________________ 5-3

Steel hull intake block ________________________________________________ 5-3

Fixing the intake block to GRP hulls ___________________________________________ 5-3

Fixing the intake block to aluminium hulls _____________________________________ 5-5

Fixing the intake block to steel hulls __________________________________________ 5-6

Electrical isolation ___________________________________________________ 5-6

Reposition the transom (if required) __________________________________________ 5-8

Refit the cut-out __________________________________________________________ 5-9

Mounting the jet unit _____________________________________________________ 5-10

Removal of components _____________________________________________ 5-10

Fit the jet unit _____________________________________________________ 5-10

Attach the transom plate __________________________________________________ 5-12

Fit the transom plate _______________________________________________ 5-13

Steering installation ______________________________________________________ 5-15

Assembling the steering tillers ________________________________________ 5-15

Centring the steering _______________________________________________ 5-15

Driveline and engine installation ____________________________________________ 5-16

Engine mounting ___________________________________________________ 5-16

Engine cooling _____________________________________________________ 5-16

Engine systems ____________________________________________________ 5-16

Exhaust systems ___________________________________________________ 5-16

Installation checks for the jet unit ___________________________________________ 5-17

Jet unit mounting __________________________________________________ 5-17

Jet unit, general ___________________________________________________ 5-17

Drive shaft ________________________________________________________ 5-18

6 - Commissioning ____________________________________________________ 6-1

Pre-launch checks_________________________________________________________ 6-1

Post launch checks ________________________________________________________ 6-2

Engine running checks (vessel moored) _______________________________________ 6-2 iv

Vessel speed and handling trials _____________________________________________ 6-3

After initial trials (after engine shutdown) _____________________________________ 6-3

7 - Fault Finding _______________________________________________________ 7-1

Jet unit faults _______________________________________________________ 7-1

Dry run faults ______________________________________________________ 7-3

Steering system faults _______________________________________________ 7-3

8 - Maintenance _______________________________________________________ 8-1

General _________________________________________________________________ 8-1

Care of jet unit ___________________________________________________________ 8-2

Preservation (pre installation) _________________________________________ 8-2

Preservation (post installation) ________________________________________ 8-2

Daily "pre use" servicing checks ________________________________________ 8-3

Servicing intervals ________________________________________________________ 8-4

Jet unit service intervals ____________________________________________________ 8-4

Jet unit servicing details ____________________________________________________ 8-5

1 - Internal water path _______________________________________________ 8-5

2 - Thrust bearing ___________________________________________________ 8-6

3 - Water seal ______________________________________________________ 8-6

4 - Anodes _________________________________________________________ 8-7

5 - Steering system __________________________________________________ 8-8

6 - Screen rake _____________________________________________________ 8-9

7 - Steering shaft and bushes __________________________________________ 8-9

8 - Steering crank ___________________________________________________ 8-9

9 - Steering shaft o-ring _____________________________________________ 8-10

10 - Hydraulic cylinders and hoses _____________________________________ 8-10

11 - Steering cables _________________________________________________ 8-10

12 - Steering cable attachment points __________________________________ 8-10

13 - Driveshaft _____________________________________________________ 8-10

14 - Check the insulation ____________________________________________ 8-10

15 - Complete jet unit _______________________________________________ 8-11

Jet surface coating procedure ________________________________________ 8-14 v

9 - Overhaul____________________________________________________________ 9-1

General information _______________________________________________________ 9-2

Introduction _______________________________________________________ 9-3

Hydraulic faults _____________________________________________________ 9-4

Recommendations for the fitting of oil seals ______________________________ 9-5

Care of jet unit paintwork ____________________________________________ 9-5

Torqueing sequence of nuts ___________________________________________ 9-6

Anode replacement _________________________________________________ 9-6

Refitting the locating dowels __________________________________________ 9-7

Reverse assembly overhaul _________________________________________________ 9-8

Reverse duct parts __________________________________________________ 9-8

Reverse duct removal ________________________________________________ 9-8

Reverse duct overhaul ______________________________________________ 9-10

Reverse cylinder removal ____________________________________________ 9-11

Reverse cylinder overhaul ___________________________________________ 9-12

Refit the reverse cylinder ____________________________________________ 9-12

Refit the reverse duct _______________________________________________ 9-13

Reconnect the reverse control cable ___________________________________ 9-14

Steering assembly overhaul ________________________________________________ 9-15

Steering cylinder removal (if used) ____________________________________ 9-16

Steering shaft removal ______________________________________________ 9-16

Check the steering shaft and bushes ___________________________________ 9-17

Replace the steering shaft bushes _____________________________________ 9-17

Steering nozzle assembly removal _____________________________________ 9-17

Inspect the steering nozzle and nozzle housing __________________________ 9-18

Nozzle assembly overhaul _________________________________________________ 9-20

Replace the steering crank bush ______________________________________ 9-20

Replace the steering pivot bush _______________________________________ 9-20

Replace the steering nozzle anode ____________________________________ 9-20

Steering assembly refitting ________________________________________________ 9-21

Fit the nozzle to the nozzle housing ____________________________________ 9-21

Refit the nozzle assembly to the tailpipe ________________________________ 9-23

Steering shaft refitting ______________________________________________ 9-24

Refit the steering cylinder/steering cable _______________________________ 9-25

Bearing housing assembly overhaul _________________________________________ 9-26

Remove the oil pump _______________________________________________ 9-26

Bearing housing dismantling _________________________________________ 9-28

Water seal removal _________________________________________________ 9-30 vi

Water seal replacement _____________________________________________ 9-32

Refit the bearing housing ____________________________________________ 9-33

Refit the oil pump __________________________________________________ 9-36

V-Belt alignment ___________________________________________________ 9-37

Tailpipe area overhaul ____________________________________________________ 9-38

Impeller - check for wear and damage: _________________________________ 9-38

Marine water bearing - checking for wear ______________________________ 9-38

Tailpipe area dismantling ____________________________________________ 9-39

Inspection of the tailpipe, marine bearing and wear ring ___________________ 9-41

Impeller overhaul __________________________________________________ 9-41

Wear ring removal and replacement ___________________________________ 9-43

Steering shaft bush replacement ______________________________________ 9-45

Marine bearing replacement _________________________________________ 9-46

Tailpipe anodes ____________________________________________________ 9-48

Tailpipe area reassembly ____________________________________________ 9-49

Intake area overhaul _____________________________________________________ 9-51

Intake internal anode _______________________________________________ 9-51

Transom plate _____________________________________________________ 9-52

Steering shaft bushes _______________________________________________ 9-53

Hatch extension (optional extra) ______________________________________ 9-54

Intake screen ______________________________________________________ 9-55

Screen rake assembly (if fitted) _______________________________________ 9-56

Oil cooler _________________________________________________________ 9-59

10 - HSRX Reverse system _________________________________________ 10-1

Introduction ____________________________________________________________ 10-1

Scope of supply ____________________________________________________ 10-2

System operation ________________________________________________________ 10-3

Prevention of corrosion ___________________________________________________ 10-3

Installing the HSRX reverse system __________________________________________ 10-3

Cable installation __________________________________________________ 10-4

Reverse control lever adjustment _____________________________________ 10-5

Commissioning the HSRX reverse system _____________________________________ 10-6

Before first start-up ________________________________________________ 10-6

Engine running checks ______________________________________________ 10-6

After commissioning ________________________________________________ 10-6 vii

Fault finding ____________________________________________________________ 10-7

Servicing intervals _______________________________________________________ 10-9

Servicing details ___________________________________________________ 10-9

Reverse cylinder overhaul ________________________________________________ 10-14

Dismantling the reverse cylinder assembly _____________________________ 10-15

Overhaul the reverse cylinder _______________________________________ 10-16

Reassemble the reverse cylinder _____________________________________ 10-17

11 - Appendix _______________________________________________________ 11-1

Conversions ____________________________________________________________ 11-2

Loctite application guide __________________________________________________ 11-3

General practice ___________________________________________________ 11-3

Primers, activators and accelerators ___________________________________ 11-3

Equivalents _______________________________________________________ 11-4

Installation checks ______________________________________________________ 11-12

Jet unit mounting _________________________________________________ 11-12

Jet unit general ___________________________________________________ 11-13

Jet systems steering _______________________________________________ 11-14

Drive shaft _______________________________________________________ 11-15

Commissioning checks ___________________________________________________ 11-16

Pre launch checks _________________________________________________ 11-16

Post launch checks ________________________________________________ 11-17

Engine checks (vessel moored) ______________________________________ 11-18

Vessel trial _______________________________________________________ 11-20

After initial trials __________________________________________________ 11-21

Jet Unit Trials & Commissioning Data _________________________________ 11-22

Temperature readings _____________________________________________ 11-22

Speed trial readings _______________________________________________ 11-22

Aluminium weld procedure _______________________________________________ 11-24

Tightening torques ______________________________________________________ 11-26

Nut tightening torques _____________________________________________ 11-26

Screw tightening torques ___________________________________________ 11-27

Stud installation __________________________________________________ 11-28

Set screws _______________________________________________________ 11-28

Hydraulic cylinder piston ___________________________________________ 11-29

Hydraulic fittings __________________________________________________ 11-29 viii

Thread lubricants _________________________________________________ 11-31

Recommendations for lubricants and oils ____________________________________ 11-32

Hydraulic fluids ___________________________________________________ 11-32

Bearing housing lubrication _________________________________________ 11-34

Joint lubrication __________________________________________________ 11-35

Drivers guide___________________________________________________________ 11-37

Starting up _______________________________________________________ 11-37

Ahead, zero speed and astern controls ________________________________ 11-37

Power assisted slowdown __________________________________________ 11-38

Steering _________________________________________________________ 11-38

Manual control of steering nozzle and reverse duct ______________________ 11-39

Emergency manouvering ___________________________________________ 11-40

Manoeuvring and docking __________________________________________ 11-40

Cruising _________________________________________________________ 11-43

Shallow water operation ___________________________________________ 11-43

Acceleration to high speed __________________________________________ 11-45

Aerated water ____________________________________________________ 11-45

Blockages (debris in the jet unit) _____________________________________ 11-45

Operating with an engine and jet unit out of service _____________________ 11-47

Shutting down the jet units after use _________________________________ 11-47

12 - Technical Drawings ___________________________________________ 12-1

HJ241 Product Manual Introduction

1-1

1 - Introduction

In This Section

Limited warranty ................................................................................................................... 1-1

Warranty and ownership registration form .......................................................................... 1-3

General safety notice ............................................................................................................ 1-4

Limited warranty Terms of coverage C.W.F. Hamilton & Co. Ltd. (HamiltonJet) warrants to the original purchaser that each new Hamilton Jet product is free from defects in material and workmanship under normal use and service for the warranty period.

In the event that a warranted defect in material or workmanship is disclosed to HamiltonJet within the warranty period, HamiltonJet's obligation is limited to, at its option, repairing or replacing the defective product, or component part at its factory or such other location as may be designated by HamiltonJet.

Defective products shall be returned to HamiltonJet or its authorised service representative for inspection with transportation charges prepaid by the purchaser to the location specified by HamiltonJet.

This warranty only applies where the product is shown, to the satisfaction of HamiltonJet, to be defective in material or workmanship during the warranty period.

HamiltonJet will supply parts required for warranty repairs free of charge and pay reasonable authorised labour costs.

To the extent permitted by law, this warranty sets out the original purchaser's exclusive remedies with respect to the product covered by this warranty. In the event that HamiltonJet determines it is unable to repair or replace any component part(s) found to be defective in materials and/or workmanship, HamiltonJet's warranty liability shall be limited to payment by HamiltonJet to the original purchaser of an amount not to exceed the value of the defective part(s), together with shipping charges, if any, incurred.

All products removed or replaced under the warranty shall become the property of HamiltonJet.

All warranty claims shall be lodged with HamiltonJet or its authorised distributor.

Warranty period The warranty period for Hamilton Jet products is limited to a period of twenty-four (24) months from the date of original shipment from the Hamilton Jet factory, or twelve (12) months from the vessel launch date, whichever occurs first.

Introduction HJ241 Product Manual

1-2

Limitation of liability This warranty is extended only to the original purchaser, and is not transferable to or assignable to any other person or entity, and does not extend to future performance.

In no event will HamiltonJet, its distributors, or affiliates be liable for any incidental, punitive or consequential losses, inconveniences, damages or other costs resulting directly or indirectly from any defect in the product covered by this warranty, including, but not limited to, loss of use, revenue or profit.

HamiltonJet reserves the right to change its product through changes in design or materials without obligation to incorporate such changes in any products previously manufactured, but any improvement or changes may be incorporated in replacement product.

Warranty does not extend to failures, damages or defects resulting from the following:

What HamiltonJet determines to be, misuse, abuse, overloading, improper application, improper transportation or storage, abnormal wear and tear, negligence, carelessness, accident, natural calamity, vandalism, fouling caused by foreign material, peculiar water conditions or chemicals, or other circumstances over which Hamilton Jet has no control.

Operation or maintenance in any way other than in accordance with the operating and maintenance instructions of HamiltonJet.

Vessel-to-shore electrical connections that change the corrosion potential of the vessel. For vessels equipped with shore power this warranty will not extend to the product unless an isolating transformer or galvanic isolator is fitted as described in the applicable HamiltonJet Product Manual.

Incorrect installation, as per the applicable HamiltonJet Product Manual and the applicable HamiltonJet Designer's Manual. This warranty will not extend to the product unless a negative earth bonding system has been installed in the vessel as specified in the respective HamiltonJet Product Manual, and a Jet Mainshaft critical speed check carried out to HamiltonJet's written satisfaction.

Warranty does not cover or provide payment or reimbursement for the following:

Any repairs or alterations carried out with the use of parts or accessories not manufactured by

HamiltonJet or its authorised representatives.

Items incorporated in any HamiltonJet product (other than by HamiltonJet) when such items have been manufactured by others or are warranted by their respective manufacturers in favour of the purchaser.

Used or reconditioned parts.

The cost of transporting the vessel to a repair facility and for all related towing, harbour, docking, slippage, lifting, moorage, launching or retrieval charges.

Any product which may have been serviced, repaired or altered in any way by anyone other than

HamiltonJet or a HamiltonJet authorised facility.

No representations or express or implied warranty except as herein stated To the extent permitted by law, this limited warranty is the only warranty extended by HamiltonJet and is in lieu of all other warranties, EXPRESSED or IMPLIED, oral or written and of all other obligations or liabilities, including without limitation any IMPLIED WARRANTIES of MERCHANTABILITY or FITNESS for a PARTICULAR PURPOSE. Except as provided in this warranty the product is sold as is, where is.

No other person or agent or distributor is authorised to modify this warranty, give any other warranty on behalf of HamiltonJet or to assume for HamiltonJet any other obligation or liability in connection with the sale of its products.

In the United States and Canada, some states and provinces do not allow limitations on duration of an implied warranty, or the exclusion or limitation of incidental or consequential damages, so the above limitations or exclusions may not apply to you. This limited warranty gives you specific legal rights and you may also have other rights, which vary from state to state.

In other countries outside the United States and Canada, you may have statutory rights which cannot be affected or limited by the terms of this Warranty.

C.W.F. Hamilton & Co. Ltd. July 2005 [Rev H]

1-3

Warranty and ownership registration form To allow HamiltonJet to complete its records and in order to assist any claim under the attached limited warranty, please complete this Warranty and Ownership Registration Form in full and return as soon as possible by post, facsimile or Email to:

The Marketing Department, C.W.F. Hamilton & Co Ltd.

PO Box 709, Christchurch, New Zealand.

Fax, +64 3 348 6969 Email, marketing@hamjet.co.nz

HamiltonJet encourages the distributor to take responsibility for ensuring the purchaser and the distributor complete this form at the time of sale and return it to HamiltonJet. Please complete one form per vessel only.

Jet Model

Serial Number(s)

Delivery Date

Commissioning / In service Date

Vessel/Project

Purchaser

Address

Contact Name

Signed

Distributor

Address

Contact Name

Signed

Office Use Only

Logged By

Project Code

Date

Introduction HJ241 Product Manual

1-4

General safety notice Warning A warning is an operation or maintenance procedure, practice, condition or statement which, if not strictly observed, could result in injury or death to personnel.

Indicated throughout this manual as shown below:

Caution:

A caution is an operation or maintenance procedure, practice condition or statement which, if not strictly observed, could result in damage to, or destruction of equipment or loss of mission effectiveness.

Note:

A note contains additional information that will help clarify a procedure.

Link:

This symbol informs you where to find additional important information on a topic.

(►Page)

1-5

Symbols Common symbols used throughout this manual:

Loctite®:

Grade of Loctite will be shown in the illustration

Multi-purpose lithium based grease or Calcium sulphate based grease

Hydraulic oil

Neutral cure RTV silicone sealant

Tenmat® T814 bedding in paste or D lube mounting grease

Zinc anti-seize compound

Marine sealant e.g.

Sikaflex® 291 and 291-LOT 3M® 4200 Terostat® 270-MS

Loctite® 515 gasket eliminator ®

Apply light heat

20:1 water and household dish washing detergent mix

Illustrations are used throughout this manual to enhance the explanation of the installation and overhaul procedures.

They may not necessarily reflect the jet model that this manual refers to.

HJ241 Product Manual Product Description

2-1

2 - Product Description

In This Section

Introduction ........................................................................................................................... 2-1

Equipment description .......................................................................................................... 2-2

Introduction Waterjets have rapidly gained acceptance as the leading means of propulsion for all types of high speed marine craft including ferries, work boats, patrol craft and pleasure boats.

Recent advances in waterjet technology have put them ahead of conventional propeller systems in both high speed performance and reliability.

Conventional propeller powered craft have several shortcomings, such as vibration, higher engine loading and susceptibility to damage from water borne debris.

Modern waterjet powered vessels offer many advantages:

High efficiency.

Rapid acceleration.

Shallow draft.

Manoeuvrability.

Smooth, quiet operation.

Lower maintenance.

Longer engine life.

Simplified installation.

No protrusions under the water.

Safety for personal working in the water near the vessel.

The waterjet unit is an ideal form of propulsion for vessels working in a marine mammal environment.

HamiltonJet pioneered the commercial development of the modern waterjet system in the early 1950’s and today we have over 30,000 units in service worldwide.

Product Description HJ241 Product Manual

2-2

Figure 1: Hamilton Quinnant Jet, Circa 1953

With a complete range of models suitable for power inputs of up to 10000kW per unit, the Hamilton waterjet is ideally suited to the efficient propulsion of a wide variety of high speed vessels, in either single or multiple jet configurations.

HamiltonJet is dedicated to the production of the highest quality waterjets and controls systems designed and manufactured to meet the requirements of the world's leading certifying authorities.

The global HamiltonJet organisation provides full support through factory support staff, regional offices and an extensive network of factory trained distributors in over 50 locations worldwide.

Equipment description The HamiltonJet HJ series is a range of highly efficient single stage waterjets suitable for propelling craft typically up to 20metres in length and 30tonnes displacement, at speeds up to 50knots. Generally, high speed diesel engines drive HJ series waterjets directly.

The HamiltonJet HM & HT series are larger single stage waterjets suitable for vessels typically up to 65m in length. Generally, high speed diesel engines drive HM & HT series waterjets via a reduction gearbox.

Mounted partly inboard at the stern of the vessel, the HamiltonJet waterjet consists of a totally integrated, jet mounted hydraulic steering, reverse and control system package.

The waterjet draws water through an intake screen at the base of the intake. The intake screen mounts flush with the hull bottom.

The pumping unit (impeller + stator) increases the pressure or "head" of the flow, which is then discharged at high velocity at the nozzle. The reaction to this high velocity jet stream provides the net thrust force, which fully transmits through the intake to the hull bottom.

A single piece balanced steering nozzle precisely directs the jet stream as commanded by the helm, providing high turning forces to either port or starboard. An independent split-duct type reverse duct, directs the jet stream back underneath the hull to provide powerful astern thrust.

The reverse duct can be set to a "zero speed" position (where the ahead and astern thrusts are balanced) at which point full steering is still available.

Selecting infinitely variable forward and reverse control by varying the position of the reverse duct combined with the highly efficient steering results in unparalleled vessel control and manoeuvrability.

2-3

Main components Intake block The Intake block forms the inlet for the jet unit. It is either moulded, welded or bolted (depending on hull material) into an opening in the hull bottom.

Intake Bolted to the intake block the intake represents the main structural body of the jet unit. It is capable of transmitting the full thrust of the jet unit to the hull bottom. High silicon aluminium alloy is used to cast the intake.

Oil cooler The jet unit is fitted with an integrated oil cooler cast into the side of the intake. This connects to the jet mounted hydraulic power unit (JHPU) via hoses.

Thrust bearing Mounted inside the bearing housing, the thrust bearing absorbs the thrust generated by the impeller.

No external thrust bearing is required.

Water seal The water seal Mounts on the mainshaft aft of the bearing housing and stops water entering the bearing housing or the vessel.

Coupling and driveshaft The coupling is mounted on the mainshaft forward of the bearing housing.

A variety of couplings are available to suit different driveshaft flanges.

The driveshaft to the waterjet connection must have axial and radial flexibility.

Impeller Mixed flow type, capable of pumping large volumes of water at relatively low pressures. Permits high propulsive coefficients to be achieved at fast vessel speeds. The cast stainless steel impeller runs within a replaceable stainless steel wear ring located in the rear section of the intake.

Tailpipe The tailpipe contains a water lubricated bearing supporting the rear of the mainshaft.

The tailpipe contains a vaned stator to remove the rotation of the water flow, allowing a uniform axial flow to the nozzle.

Steering nozzle After the water flow passes through the impeller and stator, it is at a high pressure and relatively low velocity.

Water flow at the nozzle outlet is at atmospheric pressure. This difference in flow pressure converts to flow velocity in the nozzle.

Correct nozzle sizing is critical to the correct operation of the jet unit.

Steering assembly Attached to the rear of the tailpipe, the steering assembly consists of a nozzle housing, nozzle insert and steering nozzle.

The steering nozzle mounts inside the nozzle housing on vertical pivot pins and rotates to port or starboard by linkages attached to an inboard steering tiller.

The nozzle insert ensures that the flow exiting the stator section reaches the final steering nozzle outlet without any disturbance by the steering mechanism, thus maximising steering efficiency.

Product Description HJ241 Product Manual

2-4

Reverse duct Can be positioned up or down by the reverse cylinder.

Incorporated into the reverse duct is a splitter which divides and angles the astern jet stream downwards and to the sides, clearing the transom and intake opening.

This stops recycling of water flow through the jet unit (which may be aerated or contain sediment) and excessive disturbance to the bottom of the waterway.

Transom plate It is bolted to the vessel transom and seals against a rubber o-ring fitted to the jet unit intake

Screen rake May be fitted as an optional extra. The screen rake is either a hand or foot operated rake mounted in the lower half of the intake, designed to clear any debris caught by the intake screen. The spring return foot pedal for operating the screen rake is mounted on the port side of the intake casing.

Dry run kit (optional extra) The jet unit can be fitted with a dry run kit as an optional extra at the customer’s request.

It is purchased at additional cost and should be requested when the initial jet order is placed.

The dry run system is typically used for man-overboard boats and lifeboats where the engines need to be started before the vessel is in the water.

The dry run kit consists of a special marine bearing which can be run dry for short periods of time. Standard rubber marine bearings cannot be run dry.

Overflow preventer/hatch extension (optional extra) The overflow preventer or hatch extension, is an optional extra for use with jet units where the water level (when the vessel is fully laden) is above the normal level of the main inspection cover.

The overflow preventer attaches to the top of the intake around the outside of the main inspection cover.

2-5

Main components

Figure 2: Jet unit, main components

Intake Intake block Inspection hatch Reverse Assembly Steering Arm Tailpipe Reverse duct Transom seal

Anodes Intake screen (obscured by intake block) Hatch extension (optional) Bearing & bearing housing Oil cooler Hydraulic oil pump Steering nozzle (obscured by reverse duct) Coupling

HJ241 Product Manual Design Basics

3-1

3 - Design Basics

In This Section

Propulsion system design ...................................................................................................... 3-1

Hull design ............................................................................................................................. 3-4

Drive lines .............................................................................................................................. 3-7

Universal driveshaft alignment ............................................................................................. 3-10

Jet mainshaft alignment ........................................................................................................ 3-12

Water offtake ........................................................................................................................ 3-13

Engine location and mounting ............................................................................................... 3-14

Dry run kit (optional extra) .................................................................................................... 3-15

Propulsion system design Jet unit selection Jet unit selection is a complex task. Consult HamiltonJet for advice in all cases.

Hull loads All loads produced by the jet unit result from the difference in momentum between the incoming and outgoing water. An exception is the torque load on the stator vanes, which remove the angular momentum of the water stream from the impeller.

Consider the following four cases when calculating maximum loads:

Full ahead.

Full reverse.

Full steering.

Full reverse & full steering.

While the jet unit loads are readily calculated, the hull reaction loads are dependent on the stiffness and rigidity of both the jet unit and the hull structure.

When providing these load estimates, the assumption is that the jet unit is restrained:

Radially at the transom (loads Lv and Ls).

Axially and sideways at the base of the transition duct (loads F and Ws).

Vertically at the transition webs (load Wv).

The following figure and tables give all relevant data for this jet unit.

Design Basics HJ241 Product Manual

3-2

Figure 3: Loads on hull

A Ahead

B Reverse

C Steering

D Steering and reverse

3-3

HJ241 Dimensions

Description Symbol Units Value Maximum power P kW 260 Waterjet angle a Degrees 5 Centreline height H Metres 0.284 Mean inlet depth h Metres 0.04 Steering to base centre Ds Metres 0.92 Reverse to base centre Dr Metres 1.25 Transom to base centre Dw Metres 0.415 Centre to reverse arm Da Metres 0.15

HJ241 Maximum hull reaction forces

Description Symbol Units Ahead / Steering

Reverse

Axial load in bottom F kN 9.1 -13.46 Side load in base Ws kN 7.8 6.37 Vertical load in base Wv kN 1.51 4.51 Vertical moment M kNm 5.39 4.73 Steering moment Ms kNm 7.18 8.84

For lower design power values, use the following approximate equation to adjust the hull reaction forces.

Your force = Kpr x listed force Where:

Your design power = Ydp Listed design power = Ldp

3-4

Hull design

Not all hull shapes are suitable for propulsion by waterjet. Contact HamiltonJet for guidelines on suitable hull shapes, performance and engine matching.

Mono hulled vessel Aerated water generated by the vessel’s bow wave must not pass directly aft to the jet unit intake(s).

A vee'd bow stem in conjunction with 10 degree minimum deadrise angle is recommended.

Mount multiple jet units as close to the keel line as possible (staggering the engines can allow closer centres).

Planing strakes, keelsons, plank keels and any other hull appendages that may create turbulent water flow into the jet unit(s) must not be fitted in front of or adjacent to the jet unit intakes. Refer to figure:

Mono hull design (► page 3-4).

For directional stability at speeds over 30knots, use monohedron (constant deadrise) hulls without appendages.

Displacement speed and warped plane (reducing deadrise going aft) hulls may need additional directional stability. Twin bilge keels are normally sufficient as these do not increase draft or interfere with water flow into the jet intake.

The jet unit must be immersed with the water line at least up to the underside of the mainshaft (at the impeller) in order to prime the jet unit when the engine is started..

For applications using twin or triple jet units, refer to the installation drawings for jet spacing dimensions.

For applications using more than three jets, contact HamiltonJet for jet unit spacing.

Mono hull design

1 Strakes inside width of intake should stop 0.5 metres aft of dynamic air/water interface.

2 Keep the shaded areas free of any appendages including water pickups.

3 Air/water interface.

4 Strake.

5 Jet unit intake.

Figure 4: Mono hull design

3-5

Multi hulled vessels It is possible to fit Jet units in catamaran and some trimaran hulls.

These types of vessels can trap air between the hulls. Make sure that this trapped air does not enter the jet unit intake(s).

To avoid this, make sure the hulls are deep in relation to the air tunnels so that the jet units sit well down in the water.

When in the ahead (up) position, the reverse duct must not project beyond the sidewalls of a catamaran or trimaran hull. This can cause substantial drag.

In all cases when using jet units with these types of hulls, consult HamiltonJet.

Figure 5: Multi hull design

Trim tabs

Find more information here (► page 4-4) regarding the fitting of trim tabs.

When moving astern, trim tabs mounted alongside the jet unit, will interfere with the reverse jetstream reducing thrust. Therefore do not mount trim tabs beside the jet unit.

Mount trim tabs under the jet unit with any control equipment mounted on either side of the jet unit.

The following diagram shows the maximum size and position of the trim tab that may be located under the jet unit.

Contact HamiltonJet if further information is required.

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Figure 6: Allowable trim tab location

1 Maximum size of trim tab 2 Upper level of trim tab 3 No trim tabs allowed in this area

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Drive lines

Loads on jet unit thrust bearing

The thrust bearing carries thrust loads from the jet unit to propel the craft. It should not be subjected to excessive loads from other sources as described below:

The thrust bearing will not withstand excessive radial loads caused by adapters and belt pulleys overhanging the jet coupling flange.

The thrust bearing will not withstand excessive loads produced by rigid drivelines which do not accommodate misalignment resulting from engine movement or hull flexing.

The driveline must not impose any axial force in the aft direction. On installation there should be a small gap between the waterjet and driveline coupling that closes when tightening the bolts.

There is a limit to the driveshaft weight that the jet unit can support.

Requirements of the driveline The driveline:

Must allow for parallel and angular misalignment.

Must allow for axial movement due to bearing end float, heat expansion, and hull flexing.

Must not exceed the allowable weight at the jet coupling. (Affected by critical speed calculation) Must have at least one torsionally flexible element of sufficiently low stiffness to prevent resonance within the operating speed range.

Does not have to transmit thrust loads as the jet unit absorbs these.

Must transmit the torque to the Jet Unit with an acceptable life expectancy.

Always do a torsional vibration analysis on the complete drive train. The vibratory torque should not exceed 10% of the nominal torque for most applications. The resultant torque must always be in the same direction and carefully checked at engine idle speed.

Engineering checks Consult all component suppliers (including driveline, engine and jet suppliers) with full driveline details to ensure suitability and compatibility of components.

Checks must include:

Critical speed check for whirling of the jet unit mainshaft: Consult HamiltonJet.

Critical speed check for whirling of the driveshaft: Consult driveline supplier.

Engine to jet alignment: Consult HamiltonJet and driveline supplier.

Torsional vibration analysis: Consult engine or torsionally flexible coupling supplier.

Critical speed checks should allow safe operation up to the engine's no load governor setting (or high idle).

Driveline options The above diagram shows the different types of driveline components and their uses. Note that this diagram is a guide only.

Always contact HamiltonJet before designing the driveline.

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Driveline components

Figure 7: Driveline components

1 Jet unit coupling 2 Double universal slip jointed driveshaft (misalignment absorbing coupling) 3 Fixed lineshaft (optional) 4 Pedestal support bracket 5 Torsionally flexible coupling 6 Flywheel 7 Jet unit 8 Engine/gearbox

Misalignment absorbing coupling The following types of misalignment absorbing couplings may be used:

Universal driveshafts These are double universal slip-jointed driveshafts, also called Cardan shafts. They bolt directly to the jet unit coupling.

Lengths range from approximately 900mm to 3,000mm. The maximum allowable weight at the jet unit coupling and the critical speed of the mainshaft will limit the length of the driveshaft.

Double element torsionally flexible coupling Use a double element torsionally flexible driveshaft with support bearings as illustrated below.

The engine is located in line with the jet unit. This type of coupling allows the engine to be flexibly mounted.

Length is from approximately 200mm (8") upwards. The maximum allowable weight at the jet unit coupling will limit the length of the driveshaft.

Examples of these couplings are Centaflex and Mega flex.

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Figure 8: Double element torsionally flexible coupling

1 Jet coupling 2 Coupling adaptor 3 Torsionally flexible coupling 4 Centring support bearing 5 Fly wheel

Torsionally flexible couplings (TFC) The torsional vibration analysis will determine the quantity and position of torsionally flexible couplings. Fit at least one TFC either:

Between the engine and the gearbox.

Immediately between the gearbox and any shafting leading to the jet unit.

Gear coupling The coupling consists of two steel hubs with crowned teeth that engage in a flanged sleeve with internal straight parallel teeth. As a result of the teeth curvature, the hubs can oscillate in the flanged sleeve if shaft misalignment occurs.

The double jointed coupling compensates for angular misalignment and radial offset while also allowing axial end float. It is torsionally rigid.

Follow the manufacturer's recommendations regarding installation and alignment.

A double jointed coupling is required.

Double element, non torsionally flexible couplings These are a metal disc or diaphragm type couplings and allow for a small angular misalignment and radial offset as well as axial movement, but are torsionally rigid.

Examples are Centadisc and Metaflex

Long drive shafts Where the distance between the gearbox flange and the coupling flange exceeds the acceptable length possible with a Cardan shaft or a double element flexible coupling assembly, then:

HamiltonJet recommends the use a fixed lineshaft supported on pedestal bearings.

Use a short Cardan shaft or double element flexible coupling assembly for connection to the jet unit.

If a TFC is not required between the gearbox and the lineshaft, then directly attach the lineshaft to the gearbox flange using normal propeller shafting criteria.

Mount the gearbox rigidly to avoid misalignment.

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Universal driveshaft alignment There are only two possible centreline locations for jet unit and gearbox.

'W' configuration 'Z' configuration Assemble universal driveshafts with the yokes (forks) in the same plane.

Install the heavier splined end of the driveshaft at the gearbox end of the driveline.

Correct running length of the shaft is with the shaft extended to half the total spline extension length.

When the TFC couples directly to a universal driveshaft, the TFC must provide a bearing to support the universal driveshaft.

When the TFC couples directly to a lineshaft supported on bearings, a support bearing is not required.

It is very important to position the engine so that the universal joints of the driveshaft have equal offset angles.

Refer to the driveshaft manufacturers recommendations for joint angles (typical range is between 1.5 and 5degrees).

Figure 9: 'W' configuration driveshaft

1 Jet coupling flange 3 Jet mainshaft axis 2 Engine / gearbox flange θ1 and θ2 must be equal If X1 = X2 and both input and output axis meet at point P, then θ1 = θ2

The best method of alignment is to mount pointers on the jet coupling (or output) flange and the engine (or input) flange. The length of each pointer should be exactly the same and equal to half the nominal distance between the two flanges.

Figure 10: 'Z' configuration driveshaft

1 Jet coupling flange 4 Engine /gearbox axis 2 Engine/coupling flange 'L' Axial distance between the universal driveshaft yokes 3 Jet mainshaft axis 'Q' Offset θ1 and θ2 must be equal Offset = L x Tanθ

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Jet coupling flange details Refer to drawing: HJ24102001 Coupling & Belts.

Moments of inertia Carry out a torsional vibration analysis for the complete driveline including engine flexible coupling, gearbox,…