Marine Engineering Manual.pdf · Engineering Manual . ... Stern Tube US - CIP Marine Engineering Manual 3/1/2010 Page 2 Multi-Groove Bearing Application Questions

CIP Marine CompositesTM

Engineering Manual

www.cipmarine.com

CIP Marine Composites - USThe composite material used for Marine applications is a laminated plastic material made by impregnating polyester fabric with thermosetting resins. The physical properties of CIP Marine Composites make it an excellent bearing material for both above below the water line. CIP Marine composites offer design engineers an attractive, cost effective alternative to the traditional materials such as bronze, brass, rubber or other urethane based materials..

Applications (Stable in both fresh and salt waters) • RudderBearings • SternTube/StrutBearings • PropellerShaftBearings • PintleBearings • Multi-GroovedBearings • ThrusterBearings • DeckMachinery • SlipwayPads • GuideStrips • Fairleads • PulleyLineBushings • General PlainBushings ThrustWashers WearPadsSolid LubricantsCIP Marine Composites are 100% bearing materials and contain molybdenum disulphide, PTFE and other proprietary lubricants dispersed evenly throughout the material reducing friction.

StandardRawTubes&SheetsSizesTubes SheetsMinimum Bore .............3/8” Minimum Thickness........1/16” Maximum Bore.............54” Maximum Thickness........6” Standard Lengths.........16” - 24” - 32” Standard Widths..............16” – 24” – 32” Standard Lengths……….24” – 36” – 48” – 60” FinishedPartsFinished/Machined parts can be manufactured to CIP or customer’s drawings. In addition to custom bearings and wear pads, spherical bearings can be made to solve misalignment problems. Parts requiring hex, square or irregular ID shapes can be produced from mandrels with the appropriate configuration. Please contact CIP for Engineering and Technical support.

CIP Marine CompositesUS Section

CIP Marine US - CIP Marine Engineering Manual 3/1/2010 Page 1

MachiningCompositeBearingsCIP Marine Composites are readily machinable by conventional machining techniques. As a general guide, it may be treated as bronze but should be machined dry, without coolant. Tooling should be tungsten carbide-tipped in order to obtain a fine finish. CIP Marine Composites are non-toxic; however, it is advisable to use adequate dust extraction during the machining process. (See “Machining” section for additional information)

ShaftMaterialsforRudders&SternTubesCIP Marine Composites work well with the following corrosion resistant, shaft materials: 316 stainless steel, Inconel, Monel, Stellite and Gunmetal. The recommended surface finish is 4 to 32 micro inches. Sharp or rough surfaces will increase bearing wear. When bearings are operating in water with high silt content, use of harder shafting, liners or carbide coatings are suggested. Filtered water flush should also be considered.

ShaftandHousingWhen replacing a bearing in an existing housing, it should be measured in three places on the length, and at 90° in order to obtain a good average diameter. If the housing is out of round, the bearing will assume that shape after installation.

An entry chamfer should be used so the OD of the bearing is not altered during press in.

When measuring the housing, if it is found to be greatly out of round or misaligned, a chocking repair compound may be used. Three of the most common products are: Chockfast Orange, Belzona and Epocast 36.

There are two methods of installing bearings with a chocking compound. The first is to hold the new bearing in place and simply pour the repair compound around it. For future replacement of the bearing, a dummy bearing with a release agent can be used. After the chocking compound has cured, the dummy bearing can be removed and the new CIP Composite bearing installed (contact the chocking supplier for information on the proper use of the repair compound). The second way is to pour the chocking compound directly around the actual replacement bearing.

CIP Marine US - CIP Marine Engineering Manual 3/1/2010 Page 2

CIP Marine CompositesUS Section

There are many effects on the bearing to take into consideration. Composite bearings require larger press fits and greater running clearances than other materials. The following questions, calculation pages, and tables will guide you through the steps to size a bearing.

Multi Groove Bearings have a number of equally spaced axial grooves that allow water to flow through the bearing for cooling and debris removal. This bearing design is normally manufactured as a full diameter bearing. Full diameter bearings are installed with an interference fit. The shipyard can press or freeze fit these bearings. If two bearings are required, it is advisable to line up the grooves of the bearings.

If the bearings are used in water that is contaminated with abrasive materials, a filtered water supply should be considered. A harder material for the shaft may also be used. The water flow rate should be a minimum of 1 to 1.5 gallons per minute per inch of shaft diameter.

The normal length to diameter ratio should be designed at 2:1. If the housing requires a longer bearing above the 2:1 ratio, the additional length that exceeds the ratio should have an increased diameter to reduce misalignment. This portion of the bearing is considered a safety bearing.

FreezeFittingFreeze fitting is the preferred method for installation of CIP Marine Bearings. CIP Composites do not become brittle during the freezing process. Freezing in liquid nitrogen is preferred. In order to protect personnel from severe burns, great care should be taken when handling liquid nitrogen and the frozen bearings. Also, adequate ventilation is necessary because oxygen is used when liquid nitrogen gassing occurs in confined areas. Consult your liquid nitrogen supplier for safety suggestions.

Obtain an insulated container that is large enough to hold the bearing with room for handling, and to retain -320° F. A plywood bottom can be attached to the bearing prior to placing in the insulated container. This will help contain the liquid nitrogen inside the bearing and will help reduce the amount required.

Once the bearing is inside the container, fill the bearing to the top with liquid nitrogen. An insulated cover should be installed on the container. The liquid nitrogen will be boiling. Wait until boiling stops, and leave the bearing in the container for an additional 25 to 30 minutes. Remove the cover and carefully check the bearing OD to see if the bearing will fit in the housing.

Remove the bearing and install in the housing. Retain the bearing while it returns to ambient temperature.

Stern Tube US - CIP Marine Engineering Manual 3/1/2010 Page 1

Multi-Groove Stern Tube Bearing US Section

Type of Vessel _________________________________________

Current Bearing Material _________________________________________

Shaft Diameter Max ______________ Min _______________

Shaft Material & Finish Matl ______________ Finish _______________

Housing Diameter Max ______________ Min _______________

Vessel Operating Area _________________________________________

Estimated Water Temperature Max ______________ Min _______________

Using Fresh Water Flush Yes ______________ No _______________

Once you have the above information, transfer it to the following calculation sheet for Stern bearings. Consult Table A1 as directed in the calculations.

Line 1 = Bearing Machine to OD Minimum

Line 2 = Bearing Machine to OD Maximum

Line 3 = Bearing Machine to ID Minimum

Line 4 = Bearing Machine to ID Maximum

Line 5 = Bearing ID Installed Minimum

Line 6 = Bearing ID Installed Maximum

Line 7 = Diameter Clearance Installed Minimum

Line 8 = Diameter Clearance Installed Maximum


Multi-Groove Bearing Application QuestionsUS Section

TABLE A1 - US DimensionsforMarineBearingsColumnA ColumnB ColumnC

Shaft Size Min. Wall Thickness

Min. Interference

Min. Shaft Clearance After Inst.

Number of Grooves

Groove Angles in °F Groove Width Groove Depth

1.12 / 2.37 .32 .006 .012 4 72.0° .312 .1562.37 / 4.00 .35 .009 .016 5 60.0° .312 .1564.00 / 5.87 .39 .013 .020 6 51.4° .375 .2505.87 / 7.87 .47 .017 .025 7 45.0° .375 .2507.87 / 9.87 .55 .022 .029 8 40.0° .500 .2509.87 / 11.87 .55 .028 .033 9 36.0° .500 .250

11.87 / 13.75 .63 .033 .038 10 32.7° .562 .31213.75 / 15.75 .63 .038 .042 11 30.0° .562 .31215.75 / 17.75 .79 .044 .046 12 27.7° .625 .37517.75 / 19.62 .79 .049 .051 13 25.7° .625 .37519.62 / 21.62 .87 .055 .055 14 24.0° .875 .43721.62 / 24.00 .87 .059 .059 15 22.5° .875 .437

Chamfer inside and outside diameter, 1/8” x 30°

TABLE B1 - US Suggested Machine Tolerance ID & OD of Marine Bearings


Tables A1 & B1US Section

Length.50 - 4 4 - 8 8 - 12 12 - 18 18 +

.50 - 3 +/- .002 +/- .002 +/- .003 +/- .004 +/- .0053 - 7 +/- .002 +/- .002 +/- .003 +/- .004 +/- .0057 - 12 +/- .002 +/- .002 +/- .004 +/- .004 +/- .00512 - 17 +/- .003 +/- .003 +/- .004 +/- .005 +/- .00517 - 32 +/- .005 +/- .005 +/- .006 +/- .006 +/- .007

NOTE: For calculating bearing size, use machining tolerance total. Total tolerance is equal to twice the tolerance in the charts. (For bearing 8 x 9.25 x 16in the total tolerance for calculation = 2 x .004” or .008”)

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Contact_______________________ Phone___________ Fax___________

Shaft Diameter_________________ Housing Diameter_________________Brg Machining Temperature___________ Brg Operating Temp____________Minimum Clearance on Diameter_____________

1) Housing Max + Interference Min, See Table A1-Column B

____________ + _______________ = ________________(1) Brg OD Min

2) Bearing OD Min (1) + Machining Tolerance, See Table B1

____________ + _______________ = ________________(2) Brg OD Max

3) Max Shaft Dia + (Bearing OD Max (2) – Housing Min) + Clearance Min, See Table A1-Column C

_________ + ( _________ - _________ ) + __________ = __________(3) Brg ID Min

4) Brg ID Min (3) + Acceptable Machining Tolerance, See Table B1

______________ + _______________ = ________________(4) Brg ID Max

5) Brg ID Min (3) – ( Brg OD Max (2) - Housing Min )

__________ - ( __________ - __________ ) = __________(5) Brg ID Installed Min

6) Brg ID Max (4) – (Brg OD Min (1) – Housing Max )

__________ - ( __________ - __________ ) = __________(6) Brg ID Installed Max

7) Brg ID Installed Min (5) - Max Shaft

__________ - ___________ = ___________ (7) Dia Clearance Installed Min

8) Brg ID Installed Max (6) - Min Shaft

__________ - ___________ = ___________ (8) Dia Clearance Installed Max


CIP Stern Tube Bearing CalculationUS Section

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____________ + _______________ = ________________(1) Brg OD Min


____________ + _______________ = ________________(2) Brg OD Max


_________ + ( _________ - _________ ) + __________ = __________(3) Brg ID Min


______________ + _______________ = ________________(4) Brg ID Max










CIP Stern Tube Bearing CalculationUS Section

Name (XXX)XXX-XXXX (XXX)XXX-XXXX

11.995 / 12.000 13.250 / 13255 68°F 40°F .038

13.255 .033 13.288

13.288 .008 13.296

12.000 13.296 13.250 .038 12.084

12.084 .008 12.092

12.084 13.296 13.250 12.038

12.092 13.288 13.255 12.059

12.038 12.000 .038

12.059 11.995 .064

As with the Stern Tube Bearings, we need to gather the pertinent information about the application of the rudder.

The wall thickness for new designs should be .04 inches x the shaft diameter plus .08 inches. When using this formula the inside diameter will reflect a reduction equal to the press fit. If a thicker wall is used some of the press will be absorbed into the wall.

Installation MethodsCIP Composite Bearings can be freeze fitted to ease installation. CIP Bearings do not become brittle during the freezing process. Liquid nitrogen is the best method; in some cases dry ice or refrigeration may also be used. In addition, hydraulic Port-a-Power units may be used.

Installation Procedure when FreezingExtreme caution is suggested in order to not get burned by the liquid nitrogen. Wear protective clothes, eye wear and gloves during this procedure. In addition, liquid nitrogen will use up oxygen when it is gassing; be sure to ventilate the work area. Consult the supplier for additional safety precautions.

Assemble a container large enough for the bearing with a few inches above the bearing when the bearing is on end. This container should be insulated due to the extreme coldness of the liquid nitrogen, (-320° F). A plywood end or bottom should be in the box. The down end of the bearing can be synthetic greased to form a seal to keep the liquid nitrogen inside the bearing.

Next, fill the inside of the bearing with liquid nitrogen to the top and place a cover over the bearing. The liquid nitrogen will be boiling. Once boiling stops, let bearing stand for an additional 25-30 minutes. Remove the cover and check the bearing OD to see that it will fit into the housing.

If the bearing size is proper, remove it from the container and proceed with the installation. Block or hold the bearing in the housing, especially if the installation is vertical. As the bearing returns to normal temperature and increases in size, the proper interference with the housing will be obtained.

Rudder US - CIP Marine Engineering Manual 3/1/2010 Page 1

Rudder BearingsUS Section

Installation Procedure with a Hydraulic Press or Port-a-PowerBefore starting to install a CIP Rudder Bearing, consult the force graph (Graph 1) to make sure you have adequate power available. If the housing is rough, the amount of force will be increased. It is very important that the housing has a lead in chamfer and that the bearing is in line with the bore.

The end of the bearing may be machined with a housing size minus .004” to .006” diameter by .75” long lead in area. This will assure that the bearing starts into the housing in a correct manner.

Rudder bearings should be retained at top and bottom. You can use shoulders, bolt on rings, other rings, or keepers to prevent the bearing from moving over time.

CIP Rudder Bearings can be produced up to 32 inches long. If there is a requirement for longer bearings, two bearings may be installed. A simple butt-joint is adequate, but some designers have used a notch-joint to lock the bearings together. An adhesive may be applied if necessary.


Rudder BearingUS Section

Installation Force for Rudder BearingsGraph 1 is estimated force required to press a CIP Rudder Bearing into a housing with a smooth surface. If the surface is rough, the force required will be increased.


Graph 1 - Installation ForceUS Section

Type of Vessel _________________________________________





Bearing Temperature @ Machining ______________




InterferenceDue to a lower modulus than metal bearings, CIP Composite Rudder Bearings require greater press fit. See the following tables for our recommended interference for bearing size, operating temperature and machining temperatures. If the bearing is operating below the water line, Table A should be used. For the upper rudder bearing that is out of the water, you may consider Tables B - D. Table E shows suggested machining tolerances. If you can reduce machining tolerances, you will reduce the maximum clearance after installation.


Rudder Bearing Application QuestionsUS Section

TableA: RecommendedMinimumBearingInterferencefor32°FOperatingTemperatureFor Bearings Machined at These Temperatures


Bearing Interference Table A - BUS Section

Dia 23°F 32°F 41°F 50°F 60°F 68°F 77°F 86°F4 .003 .004 .005 .006 .007 .008 .009 .0106 .006 .007 .009 .010 .012 .013 .015 .0168 .009 .011 .013 .015 .017 .018 .021 .023

10 .012 .015 .017 .020 .022 .025 .027 .02912 .016 .019 .022 .024 .028 .031 .033 .03614 .019 .023 .026 .030 .033 .037 .040 .04316 .022 .026 .030 .034 .038 .044 .046 .05018 .026 .030 .035 .039 .044 .048 .053 .05720 .030 .039 .041 .044 .049 .054 .059 .06422 .034 .039 .044 .050 .055 .061 .066 .07124 .035 .041 .047 .053 .060 .065 .071 .07626 .040 .046 .053 .059 .066 .072 .079 .08528 .043 .050 .057 .064 .071 .077 .085 .09230 .047 .055 .062 .069 .077 .084 .092 .09632 .051 .059 .067 .075 .083 .090 .098 .106

TableB: RecommendedMinimumBearingInterferencefor14°FOperatingTemperatureFor Bearings Machined at These Temperatures

Dia 60°F 68°F 77°F 86°F4 .009 .010 .011 .0126 .015 .016 .018 .0198 .021 .023 .025 .027

10 .027 .029 .032 .03412 .033 .036 .039 .04214 .040 .043 .047 .05016 .046 .050 .054 .05818 .053 .057 .061 .06620 .059 .064 .069 .07422 .066 .070 .077 .08224 .071 .077 .083 .08926 .078 .085 .091 .09828 .085 .092 .098 .10530 .092 .099 .106 .11432 .098 .106 .114 .122


Bearing Interference Table C - DUS Section

Dia 60°F 68°F 77°F 86°F4 .011 .012 .013 .0146 .018 .019 .020 .0228 .025 .027 .029 .030

10 .032 .034 .037 .03912 .040 .042 .045 .04814 .047 .050 .054 .05616 .053 .058 .062 .06618 .061 .066 .070 .07520 .068 .074 .079 .08422 .077 .082 .088 .09324 .083 .089 .095 .09826 .091 .098 .104 .11128 .098 .105 .112 .11930 .110 .114 .121 .12832 .120 .130 .138 .146

TableC: RecommendedMinimumBearingInterferencefor-4°FOperatingTemperatureFor Bearings Machined at These Temperatures

Dia 60°F 68°F 77°F 86°F4 .013 .014 .015 .0166 .021 .022 .024 .0258 .029 .031 .033 .035

10 .037 .039 .042 .04412 .045 .048 .051 .05414 .053 .057 .061 .06416 .062 .065 .070 .07318 .070 .075 .079 .08420 .078 .084 .088 .09422 .088 .093 .098 .10424 .094 .100 .106 .11226 .104 .110 .117 .12328 .112 .120 .126 .13330 .121 .128 .136 .14332 .138 .146 .154 .161

TableD: RecommendedMinimumBearingInterferencefor-22°FOperatingTemperatureFor Bearings Machined at These Temperatures

Clearance for Rudder BearingsGraph 2 is for selecting clearances between the shaft and the bearing. Both the Recommended Classification Upper Limit and the Recommended Lower Limit are indicated on this graph. If you are not applying classification rules you may select a clearance between the upper and lower limits.


Graph 2 - ClearanceUS Section

TableE: MachiningToleranceforIDandOD

Length.50 - 4 4 - 8 8 - 12 12 - 18 18 +

.50 - 3 +/- .002 +/- .002 +/- .003 +/- .004 +/- .0053 - 7 +/- .002 +/- .002 +/- .003 +/- .004 +/- .0057 - 12 +/- .002 +/- .002 +/- .004 +/- .004 +/- .00512 - 17 +/- .003 +/- .003 +/- .004 +/- .005 +/- .00517 - 32 +/- .005 +/- .005 +/- .006 +/- .006 +/- .007

If your machine shop can hold tighter tolerances, the maximum clearance will be reduced. As length increases tolerances will also increase.

NOTE: For calculating bearing size, use machining tolerance total. Total tolerance is equal to twice the tolerance in the charts. (For bearing 8 x 9.25 x 16in the total tolerance for calculation = 2 x .004” or .008”)

OnceyouhavetheinformationfromtheApplicationQuestions,transferittothefollowingcalculationsheetforRudderBearings.ConsultTablesA-Easdirectedinthecalculations.










Table E - Machining ToleranceUS Section

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Shaft Diameter_________________ Housing Diameter_________________Brg Machining temperature___________ Brg Operating Temp____________Minimum Clearance on Diameter______ Graph 2

1) Housing Max + Interference Min, See Tables A – D: Operating Temp

____________ + _______________ = ________________(1) Brg OD Min

2) Bearing OD Min (1) + Machining Tolerance, See Table E

____________ + _______________ = ________________(2) Brg OD Max

3) Max Shaft Dia + (Bearing OD Max (2) – Housing Min) + Clearance Min, Graph 2

_________ + ( _________ - _________ ) + __________ = __________(3) Brg ID Min

4) Brg ID Min (3) + Acceptable Machining Tolerance, See Table E

______________ + _______________ = ________________(4) Brg ID Max










CIP Rudder Bearing CalculationUS Section O

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________ + _______ = _______(1) Brg OD Min


________ + _______ = ________(2) Brg OD Max


________ + ( _______ - ________ ) + _____ = ________(3) Brg ID Min


________ + ______ = ________(4) Brg ID Max


________ - ( _______ - ________ ) = ________(5) Brg ID Installed Min


________ - ( _______ - ________ ) = ________(6) Brg ID Installed Max


________ - ________ = ______ (7) Dia Clearance Installed Min


________ - ________ = ______ (8) Dia Clearance Installed Max


CIP Rudder Bearing CalculationUS Section

Name (xxx)xxx-xxxx (xxx)xxx-xxxx

15.995 / 16.000 17.500 / 17.505 68°F 32°F .05

17.505 .044 17.549

17.549 .008 17.557

16.000 17.557 17.500 .05 16.107

16.107 .008 16.115

16.107 17.557 17.500 16.050

16.115 17.549 17.505 16.071

16.050 16.000 .050

16.071 15.995 .079

CIP Marine Composites - MetricThe composite material used for Marine applications is a laminated plastic material made by impregnating polyester fabric with thermosetting resins. The physical properties of CIP Marine Composites make it an excellent bearing material for both above below the water line. CIP Marine composites offer design engineers an attractive, cost effective alternative to the traditional materials such as bronze, brass, rubber or other urethane based materials..

Applications (Stable in both fresh and salt waters) • RudderBearings • SternTube/StrutBearings • PropellerShaftBearings • PintleBearings • Multi-GroovedBearings • ThrusterBearings • DeckMachinery • SlipwayPads • GuideStrips • Fairleads • PulleyLineBushings • General PlainBushings ThrustWashers WearPadsSolid LubricantsCIP Marine Composites are 100% bearing materials and contain molybdenum disulphide, PTFE and other proprietary lubricants dispersed evenly throughout the material reducing friction.

StandardRawTubes&SheetsSizesTubes SheetsMinimum Bore .............9.5mm Minimum Thickness........1.59mm Maximum Bore.............1371mm Maximum Thickness.......152.40mmStandard Lengths.........406 - 609 - 812mm Standard Widths..............406 – 609 – 812mm Standard Lengths……….609–914–1219–1524mm FinishedPartsFinished/Machined parts can be manufactured to CIP or customers drawings. In addition to custom bearings and wear pads, spherical bearings can be made to solve misalignment problems. Parts requiring hex, square or irregular ID shapes can be produced from mandrels with the appropriate configuration. Please contact CIP for Engineering and Technical support.

CIP Marine CompositesMetric Section

CIP Marine Metric- CIP Marine Engineering Manual 3/1/2010 Page 1

MachiningCompositeBearingsCIP Marine Composites are readily machinable by conventional machining techniques. As a general guide, it may be treated as bronze but should be machined dry, without coolant. Tooling should be tungsten carbide-tipped in order to obtain a fine finish. CIP Marine Composites are non-toxic; however, it is advisable to use adequate dust extraction during the machining process. (See “Machining” section for additional information)

ShaftMaterialsforRudders&SternTubesCIP Marine Composites work well with the following corrosion resistant, shaft materials: 316 stainless steel, Inconel, Monel, Stellite and Gunmetal. The recommended surface finish is 1.02x10-4 to 8.13x10-5 mm. Sharp or rough surfaces will increase bearing wear. When bearings are operating in water with high silt content, use of harder shafting, liners or carbide coatings are suggested. Filtered water flush should also be considered.

ShaftandHousingWhen replacing a bearing in an existing housing, it should be measured in three places on the length, and at 90° in order to obtain a good average diameter. If the housing is out of round, the bearing will assume that shape after installation.

An entry chamfer should be used so the OD of the bearing is not altered during press in.

When measuring the housing, if it is found to be greatly out of round or misaligned, a chocking repair compound may be used. Three of the most common products are: Chockfast Orange, Belzona and Epocast 36.

There are two methods of installing bearings with a chocking compound. The first is to hold the new bearing in place and simply pour the repair compound around it. For future replacement of the bearing, a dummy bearing with a release agent can be used. After the chocking compound has cured, the dummy bearing can be removed and the new CIP Composite bearing installed (contact the chocking supplier for information on the proper use of the repair compound). The second way is to pour the chocking compound directly around the actual replacement bearing.

CIP Marine Metric - CIP Marine Engineering Manual 3/1/2010 Page 2

CIP Marine CompositesMetric Section

There are many effects on the bearing to take into consideration. Composite bearings require larger press fits and greater running clearances than other materials. The following questions, calculation pages, and tables will guide you through the steps to size a bearing.

Multi Groove Bearings have a number of equally spaced axial grooves that allow water to flow through the bearing for cooling and debris removal. This bearing design is normally manufactured as a full diameter bearing. Full diameter bearings are installed with an interference fit. The shipyard can press or freeze fit these bearings. If two bearings are required, it is advisable to line up the grooves of the bearings.

If the bearings are used in water that is contaminated with abrasive materials, a filtered water supply should be considered. A harder material for the shaft may also be used. The water flow rate should be a minimum of 96.3 to 144.3 liters per minute per millimeter of shaft diameter.

The normal length to diameter ratio should be designed at 2:1. If the housing requires a longer bearing above the 2:1 ratio, the additional length that exceeds the ratio should have an increased diameter to reduce misalignment. This portion of the bearing is considered a safety bearing.

FreezeFittingFreeze fitting is the preferred method for installation of CIP Marine Bearings. CIP Composites do not become brittle during the freezing process. Freezing in liquid nitrogen is preferred. In order to protect personnel from severe burns, great care should be taken when handling liquid nitrogen and the frozen bearings. Also, adequate ventilation is necessary because oxygen is used when liquid nitrogen gassing occurs in confined areas. Consult your liquid nitrogen supplier for safety suggestions.

Obtain an insulated container that is large enough to hold the bearing with room for handling, and to retain -195.56° C. A plywood bottom can be attached to the bearing prior to placing in the insulated container. This will help contain the liquid nitrogen inside the bearing and will help reduce the amount required.

Once the bearing is inside the container, fill the bearing to the top with liquid nitrogen. An insulated cover should be installed on the container. The liquid nitrogen will be boiling. Wait until boiling stops, and leave the bearing in the container for an additional 25 to 30 minutes. Remove the cover and carefully check the bearing OD to see if the bearing will fit in the housing.

Remove the bearing and install in the housing. Retain the bearing while it returns to ambient temperature.

Stern Tube Metric- CIP Marine Engineering Manual 3/1/2010 Page 1

Multi-Groove Stern Tube Bearing Metric Section

Type of Vessel _________________________________________








Once you have the above information, transfer it to the following calculation sheet for Stern bearings. Consult Table A1 as directed in the calculations.









Stern Tube Metric - CIP Marine Engineering Manual 3/1/2010 Page 2

Multi-Groove Bearing Application QuestionsMetric Section

TABLE A1 - Metric DimensionsforMarineBearingsColumnA ColumnB ColumnC

Shaft Size Min. Wall Thickness

Min. Interference

Min. Shaft Clearance After Inst.

Number of Grooves

Groove Angles in °C Groove Width Groove Depth

28.45/60.20 8.13 .15 .30 4 72.0° 7.92 3.9660.20/101.60 8.89 .23 .41 5 60.0° 7.92 3.96

101.60/149.10 9.91 .33 .51 6 51.4° 9.53 6.35149.10/199.90 11.94 .43 .64 7 45.0° 9.53 6.35199.90/250.70 13.97 .56 .74 8 40.0° 12.70 6.35250.70/301.50 13.97 .71 .84 9 36.0° 12.70 6.35301.50/349.25 16.00 .84 .97 10 32.7° 14.27 7.92349.25/400.05 16.00 .97 1.07 11 30.0° 14.27 7.92400.05/450.85 20.07 1.12 1.17 12 27.7° 15.88 9.53450.85/498.35 20.07 1.24 1.30 13 25.7° 15.88 9.53498.35/549.15 22.10 1.40 1.40 14 24.0° 22.23 11.10549.15/609.60 22.10 1.50 1.50 15 22.5° 22.23 11.10

Chamfer inside and outside diameter, 3.18mm x 30°

TABLE B1 - Metric Suggested Machine Tolerance ID & OD of Marine Bearings


Tables A1 & B1Metric Section

Length12.7-101.6 101.6-203.2 203.2-304.8 304.8-457.2 457.2 +

12.7-76.2 +/- .051 +/- .051 +/- .076 +/- .101 +/- .12776.2-177.8 +/- .051 +/- .051 +/- .076 +/- .101 +/- .127177.8-304.8 +/- .051 +/- .051 +/- .101 +/- .101 +/- .127304.8-431.8 +/- .076 +/- .076 +/- .101 +/- .127 +/- .127431.8-812.8 +/- .127 +/- .127 +/- .152 +/- .152 +/- .178

NOTE: For calculating bearing size, use machining tolerance total. Total tolerance is equal to twice the tolerance in the charts. (For bearing 203 x 235 x 406mm the total tolerance for calculation = 2 x .101 or .202)

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____________ + _______________ = ________________(1) Brg OD Min


____________ + _______________ = ________________(2) Brg OD Max


_________ + ( _________ - _________ ) + __________ = __________(3) Brg ID Min


______________ + _______________ = ________________(4) Brg ID Max










CIP Stern Tube Bearing CalculationMetric Section

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____________ + _______________ = ________________(1) Brg OD Min


____________ + _______________ = ________________(2) Brg OD Max


_________ + ( _________ - _________ ) + __________ = __________(3) Brg ID Min


______________ + _______________ = ________________(4) Brg ID Max










CIP Stern Tube Bearing CalculationMetric Section

Name (XXX)XXX-XXXX (XXX)XXX-XXXX

304.67/304.80 336.55/336.68 20°C 4.44°C .97

336.68 .84 337.52

337.52 .20 337.72

304.80 337.72 336.55 .97 306.94

306.94 .20 307.14

306.94 337.72 336.55 305.77

307.14 337.52 336.68 306.30

305.77 304.80 .97

306.30 304.67 1.63

As with the Stern Tube Bearings, we need to gather the pertinent information about the application of the rudder.

The wall thickness for new designs should be 1.02mm x the shaft diameter plus 2.03mm. When using this formula the inside diameter will reflect a reduction equal to the press fit. If a thicker wall is used some of the press will be absorbed into the wall.

Installation MethodsCIP Composite Bearings can be freeze fitted to ease installation. CIP Bearings do not become brittle during the freezing process. Liquid nitrogen is the best method; in some cases dry ice or refrigeration may also be used. In addition, hydraulic Port-a-Power units may be used.

Installation Procedure when FreezingExtreme caution is suggested in order to not get burned by the liquid nitrogen. Wear protective clothes, eye wear and gloves during this procedure. In addition, liquid nitrogen will use up oxygen when it is gassing; be sure to ventilate the work area. Consult the supplier for additional safety precautions.

Assemble a container large enough for the bearing with a few inches above the bearing when the bearing is on end. This container should be insulated due to the extreme coldness of the liquid nitrogen, (-195.56° C). A plywood end or bottom should be in the box. The down end of the bearing can be synthetic greased to form a seal to keep the liquid nitrogen inside the bearing.

Next, fill the inside of the bearing with liquid nitrogen to the top and place a cover over the bearing. The liquid nitrogen will be boiling. Once boiling stops, let bearing stand for an additional 25-30 minutes. Remove the cover and check the bearing OD to see that it will fit into the housing.

If the bearing size is proper, remove it from the container and proceed with the installation. Block or hold the bearing in the housing, especially if the installation is vertical. As the bearing returns to normal temperature and increases in size, the proper interference with the housing will be obtained.

Rudder Metric - CIP Marine Engineering Manual 3/1/2010 Page 1

Rudder BearingsMetric Section

Installation Procedure with a Hydraulic Press or Port-a-PowerBefore starting to install a CIP Rudder Bearing, consult the force graph (Graph 1) to make sure you have adequate power available. If the housing is rough, the amount of force will be increased. It is very important that the housing has a lead in chamfer and that the bearing is in line with the bore.

The end of the bearing may be machined with a housing size minus .10 to .15mm diameter by 19.05mm long lead in area. This will assure that the bearing starts into the housing in a correct manner.

Rudder bearings should be retained at top and bottom. You can use shoulders, bolt on rings, other rings, or keepers to prevent the bearing from moving over time.

CIP Rudder Bearings can be produced up to 812mm long. If there is a requirement for longer bearings, two bearings may be installed. A simple butt-joint is adequate, but some designers have used a notch-joint to lock the bearings together. An adhesive may be applied if necessary.


Rudder BearingMetric Section

Installation Force for Rudder BearingsGraph 1 is estimated force required to press a CIP Rudder Bearing into a housing with a smooth surface. If the surface is rough, the force required will be increased.


Graph 1 - Installation ForceMetric Section

Type of Vessel _________________________________________





Bearing Temperature @ Machining ______________




InterferenceDue to a lower modulus than metal bearings, CIP Composite Rudder Bearings require greater press fit. See the following tables for our recommended interference for bearing size, operating temperature and machining temperatures. If the bearing is operating below the water line, Table A should be used. For the upper rudder bearing that is out of the water, you may consider Tables B - D. Table E shows suggested machining tolerances. If you can reduce machining tolerances, you will reduce the maximum clearance after installation.


Rudder Bearing Application QuestionsMetric Section

TableA: RecommendedMinimumBearingInterferencefor0°COperatingTemperatureFor Bearings Machined at These Temperatures


Bearing Interference Table A - BMetric Section

Dia -5°C 0°C 5°C 10°C 15.6°C 20°C 25°C 30°C101.60 .08 .10 .13 .15 .18 .20 .23 .25152.40 .15 .18 .23 .25 .30 .33 .38 .41203.20 .23 .28 .33 .38 .43 .46 .53 .58254.00 .30 .38 .43 .51 .56 .64 .69 .74304.80 .41 .48 .56 .61 .71 .79 .84 .91355.60 .48 .58 .66 .76 .84 .94 1.02 1.09406.40 .56 .66 .76 .86 .97 1.12 1.17 1.27457.20 .66 .76 .89 .99 1.12 1.22 1.35 1.45508.00 .76 .99 1.04 1.12 1.24 1.37 1.50 1.63558.80 .86 .99 1.12 1.27 1.40 1.55 1.68 1.80609.60 .89 1.04 1.19 1.35 1.52 1.65 1.80 1.93660.40 1.02 1.17 1.35 1.50 1.68 1.83 2.01 2.16711.20 1.09 1.27 1.45 1.63 1.80 1.96 2.16 2.34762.00 1.19 1.40 1.57 1.75 1.96 2.13 2.34 2.44812.80 1.30 1.50 1.70 1.91 2.11 2.29 2.49 2.69

TableB: RecommendedMinimumBearingInterferencefor-10°COperatingTemperatureFor Bearings Machined at These Temperatures

Dia 15.6°C 20°C 25°C 30°C101.60 .23 .25 .28 .30152.40 .38 .41 .46 .48203.20 .53 .58 .64 .69254.00 .69 .74 .81 .86304.80 .84 .91 .99 1.07355.60 1.02 1.09 1.19 1.27406.40 1.17 1.27 1.37 1.47457.20 1.35 1.45 1.55 1.68508.00 1.50 1.63 1.75 1.88558.80 1.68 1.78 1.96 2.08609.60 1.80 1.96 2.11 2.26660.40 1.98 2.16 2.31 2.49711.20 2.16 2.34 2.49 2.67762.00 2.34 2.51 2.69 2.90812.80 2.49 2.69 2.90 3.10


Bearing Interference Table C - DMetric Section

Dia 15.6°C 20°C 25°C 30°C101.60 .28 .30 .33 .36152.40 .46 .48 .51 .56203.20 .64 .69 .74 .76254.00 .81 .86 .94 .99304.80 1.02 1.07 1.14 1.22355.60 1.19 1.27 1.37 1.42406.40 1.35 1.47 1.57 1.68457.20 1.55 1.68 1.78 1.91508.00 1.73 1.88 2.01 2.12558.80 1.96 2.08 2.24 2.36609.60 2.11 2.26 2.41 2.49660.40 2.31 2.49 2.64 2.82711.20 2.49 2.67 2.84 3.02762.00 2.79 2.90 3.07 3.25812.80 3.05 3.30 3.51 3.71

TableC: RecommendedMinimumBearingInterferencefor-20°COperatingTemperatureFor Bearings Machined at These Temperatures

Dia 15.6°C 20°C 25°C 30°C101.60 .33 .36 .38 .41152.40 .53 .56 .61 .64203.20 .74 .79 .84 .89254.00 .94 .99 1.07 1.12304.80 1.14 1.22 1.30 1.37355.60 1.35 1.45 1.55 1.63406.40 1.57 1.65 1.78 1.85457.20 1.78 1.91 2.01 2.13508.00 1.98 2.13 2.24 2.39558.80 2.24 2.36 2.49 2.64609.60 2.39 2.54 2.69 2.84660.40 2.64 2.79 2.97 3.12711.20 2.84 3.05 3.20 3.38762.00 3.07 3.25 3.45 3.63812.80 3.51 3.71 3.91 4.09

TableD: RecommendedMinimumBearingInterferencefor-5.6°COperatingTemperatureFor Bearings Machined at These Temperatures

Clearance for Rudder BearingsGraph 2 is for selecting clearances between the shaft and the bearing. Both the Recommended Classification Upper Limit and the Recommended Lower Limit are indicated on this graph. If you are not applying classification rules you may select a clearance between the upper and lower limits.


Graph 2 - ClearanceMetric Section

TableE: MachiningToleranceforIDandOD

If your machine shop can hold tighter tolerances, the maximum clearance will be reduced. As length increases tolerances will also increase.

NOTE: For calculating bearing size, use machining tolerance total. Total tolerance is equal to twice the tolerance in the charts. (For bearing 203 x 235 x 406mm the total tolerance for calculation = 2 x .101 or .202)

OnceyouhavetheinformationfromtheApplicationQuestions,transferittothefollowingcalculationsheetforRudderBearings.ConsultTablesA-Easdirectedinthecalculations.










Table E - Machining ToleranceMetric Section

Length12.7-101.6 101.6-203.2 203.2-304.8 304.8-457.2 457.2 +

12.7-76.2 +/- .051 +/- .051 +/- .076 +/- .101 +/- .12776.2-177.8 +/- .051 +/- .051 +/- .076 +/- .101 +/- .127177.8-304.8 +/- .051 +/- .051 +/- .101 +/- .101 +/- .127304.8-431.8 +/- .076 +/- .076 +/- .101 +/- .127 +/- .127431.8-812.8 +/- .127 +/- .127 +/- .152 +/- .152 +/- .178

Dia

met

er




____________ + _______________ = ________________(1) Brg OD Min


____________ + _______________ = ________________(2) Brg OD Max


_________ + ( _________ - _________ ) + __________ = __________(3) Brg ID Min


______________ + _______________ = ________________(4) Brg ID Max










CIP Rudder Bearing CalculationMetric Section O

ri

gi

na

l C

Op

y




________ + _______ = _______(1) Brg OD Min


________ + _______ = ________(2) Brg OD Max


________ + ( _______ - ________ ) + _____ = ________(3) Brg ID Min


________ + ______ = ________(4) Brg ID Max


________ - ( _______ - ________ ) = ________(5) Brg ID Installed Min


________ - ( _______ - ________ ) = ________(6) Brg ID Installed Max


________ - ________ = ______ (7) Dia Clearance Installed Min


________ - ________ = ______ (8) Dia Clearance Installed Max


CIP Rudder Bearing CalculationMetric Section

Name (xxx)xxx-xxxx (xxx)xxx-xxxx

406.27/406.40 444.50/444.63 20°C 0°C 1.27

444.63 1.12 445.75

445.75 .20 445.95

406.40 445.95 444.50 1.27 409.12

409.12 .20 409.32

409.12 445.95 444.50 407.67

409.32 445.75 444.63 408.20

407.67 406.40 1.27

408.20 406.27 1.93

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Marine Engineering Manual.pdf · Engineering Manual . ... Stern Tube US - CIP Marine Engineering Manual 3/1/2010 Page 2 Multi-Groove Bearing Application Questions