CA1220387A - Means for mounting a thruster propeller unit - Google Patents
Means for mounting a thruster propeller unitInfo
- Publication number
- CA1220387A CA1220387A CA000449871A CA449871A CA1220387A CA 1220387 A CA1220387 A CA 1220387A CA 000449871 A CA000449871 A CA 000449871A CA 449871 A CA449871 A CA 449871A CA 1220387 A CA1220387 A CA 1220387A
- Authority
- CA
- Canada
- Prior art keywords
- tubular member
- lifting line
- vessel
- bottom plating
- lock chamber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Earth Drilling (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The mounting of a thruster propeller unit in the bottom plating of a vessel is facilitated by the use of lifting lines, operable from within the vessel. Each line is made to pass a lock chamber adjacent to an opening in the bottom plating, outside the opening where the thruster propeller is to be fitted. The lock chamber includes a first, rigid tubular member, which is the housing for a slide valve, as well as a second tubular member, which is resilient at least in the transverse direction. The two tubular members define a passage being substantially wider than the diameter of the lifting line. The second tubular member is at its top provided with a sealing sleeve which fits around the line. The locking chamber is connected to a source of compressed air, which makes it possible to main-tain a pressure within the chamber balancing the pressure of the surrounding water.
The mounting of a thruster propeller unit in the bottom plating of a vessel is facilitated by the use of lifting lines, operable from within the vessel. Each line is made to pass a lock chamber adjacent to an opening in the bottom plating, outside the opening where the thruster propeller is to be fitted. The lock chamber includes a first, rigid tubular member, which is the housing for a slide valve, as well as a second tubular member, which is resilient at least in the transverse direction. The two tubular members define a passage being substantially wider than the diameter of the lifting line. The second tubular member is at its top provided with a sealing sleeve which fits around the line. The locking chamber is connected to a source of compressed air, which makes it possible to main-tain a pressure within the chamber balancing the pressure of the surrounding water.
Description
I
file proselyte inverltioll relates to means for noun-tying a tllrusLer propeller unlit.
offshore vessels, especially those of the semi sub-mersibLe type, are often equipped with thruster propellers, which are rotatable 360 and are used for propulsioll, steer-iffy as well as for positionirlg of the vessel. lounging and dismounl-irlg of these thruster propeller units is a difficult and tickles work.
Us the propeller UllitS are mutilated below tile both Tom platoon of the vessel, the space within the latter, adjacent: to the location of mou-ltjrlg must be separated from the surroulldirlg water. on occasional screening around the operlillcJ, where the propeller Unlit is to be rmoullted, can easily be arranc3ed, but the lines used for performing the terlrlinating part of the lifting of tile unit into the opera-in has hitherto caused many problems.
Usually there is a vertical tube for equal line, which from a hole irk Lowe bottom platirlg, within the vessel, reaches us) to or somewhat above the water level. As the decks of the pontoons carrying the semi submersible vessel during a mountirlg operation will be located just above water level, the space rema:irli-lg for the lifting gear will be rather restricted. Roy required space for the lifting gear must be provided above the deck of the pontoorl, in local-tries needed for other purposes, for instance as bunker or ballast tanks.
'file present inverltion provides efficient means, which do not require much space, for passing a lifting line through the bottom platirlg, and which permits some side ward movement of the line.
. .
Z~338~7 Tile inventioll thus provides means for Insulting a luster propeller unit in an opelli1lg in the bottle struck lure of a vessel end colllpri.sil)g a least two lif.i.nc3 fines, pass.irlc3 out throug11 the bottom plating outside of the opera-S in all beirlg attachable to the thruster propeller Unlit, when the latter has beer brought to a position adjacent to tile opetlillcJ, in which each li.ftinc3 line is passed trackage a plurality ox lock chambers mourlted at the bottle plating, cacti perm:itti.rlg the passage of a lifting lisle and adjacent to tile bottom platirlg including a first, rouges tubular mulberry, ellclos~ g a passage substantially wider tall the cl.iallleter of the liftincJ line, and a second, tubular menlber wtl.i.cll is resili.el-lt at least transversely to the lotting line, said seconc1 member, at its end remote from the bottom pl.at:illcJ, supportincJ a packing sealing around the associated lofting line, end tloistillg means withirl the vessel for operati.llcJ said lines.
lo aft aspect thereof the present inverltic)ll pro-v:Ldes meals Err moulltillt3 a thruster Unlit in an open:irlg in the bottom structure owe a vessel and comprising at least two lotting fines, operable from inside the vessel, passing out throucJtl the bottom platting outside of the operling and being attachable to the thruster propeller unit, when the latter has been brought to a position adjacent to the openillc3, ion Wtl.iCtl each lifting line is passed through a lock chamber at the bottom plating, and adjacent to the latter includes a first, rigid tubular member, enclosing a passage sub Stan-tidally winder than the diameter of the lifting line, as well as a second, tubular member being resiliellt at least transversely to the lifting line resilient tubular member arid :imcludinc3 a bellows-shaped portion, fitted between two flunkies, which are held together by means of a namer of si.dewardly movable, rigid rods, the second tubular member, at its end remote from the bottom plating carrying a pack-inch scaling around the lifting line.
I -I
The lock chamber is preferably corlllected to a Sioux s~pplyillcJ a gaseous fluid at a pressure suited to balallce eye pressure of the surrounding water. 'rho first tubular mulberry is advarltageously formed as the housing for a closure valve.
'rho second, resilient member preferably includes a belk:~ws-shaped portrayal, fitted bitterly two flunkies, WtliCh are Hillel together by meals of a nunlbe.r of sidewardly move able, rouged rods. 'I've upper of the two flanges, throuc3h which the lifting Lyon passes out from the lock challlber, is preferably provided with a sealillg sleeve comprising a nulllber. of split rubber washers.
A cowl operable from withal the vessel and adapted to clockwise the mourlti.rlg openillg is preferably formed arid adapt ted to permit a waterti.cJht fitting of the thruster propeller unlit in the portion of the bottom platincJ surrourlcli.llg the openi.llg durillg a preliminary stage of the mounting opera-twill.
The inverlti.on will below be described with reference to the accompanying drawings, in which:-Figure 1 shows an end view of a semi submersible offshore vessel during the mounting of a thruster propeller Unlit;
Figure 2 shows a cross section through a portion of one of the ponytails owe the vessel; and Figure 3 shows a detail of the lock chamber at the lift line.
, ~2~3~7 Thruster propellers may be used with various types old vessels and Lloatirlg bodies, and the offshore vessel shown - 2b -Jo ~ZV38'7 in Figure 1 is one example only of a possible use. Toe figure illustrates one manner of mounting and dismounting the housing of a thruster propeller unit.
The offshore vessel shown comprises a working platform lo which by means of columns if is carried from two pony loons 12. Upon the plat~orln there is a superstructure 13 providing housing for the staff, and including workshop, stores as Furthermore there is a derrick 14 and a number ox cranes 15, 16, 17.
The vessel is shown in transit position, i.e. the decks of the pontoons 12 are located just above the water level.
Each pontoon 12 is provided with a number of thruster pro-poller units 18, which are located below the bottom plating of the pontoons.
The thruster propeller units are, in the manner better explained in connection with the following figures, mounted in openings in the bottom plating. In the manner indicated in the loft part ox Figure l a thruster propeller unit 18 may be moved by means of wires lo, 20 from the cranes from a position I upon barge, to a position II, and then to a post-lion III directly below the intended opening. From position III the unit is lifted into the opening by meats of lines operable from within the pontoon.
The attachment of these lines and the releasing of the crane wires will require the assistance of divers. Alterna-lively the transfer to position III may occur by means of some displacing carrier, which by divers is guided to the desired position below the opening.
The pontoons 12 will in the conventional manner he pro-voided with ballast tanks, as well as with pumping machinery connectable thereto for deter milling the draft of the pony loons. Furthermore there is an engine room 22 serving each thruster propeller unit.
In Figure 2 the bottom plating of a pontoon is denoted ho 23, and an opening 24 in the plating is surrounded by a reinforced plate structure 25. A flange at the thruster pro-poller unit wow be bolted watertight to this structure.
The final lifting of a unit is brought about by means Jo 3~7 of a number of lifting lines 26, preferably three, even if two only are shown in the (drawing. essay lines are operable from within the engine room 22, and will sealingly pass through the bottom plating by way of lock chambers 27, located outside the opening 24 for the thruster unit.
The lines 26 are connected to lifting gears 28 of arbitrary known type.
Figure 2 shows, in broken Hines a thruster unit 18 hanging in the crane wires 19 and 20, and in full lines just lifted into the opening 24 by means of lie lines 26. When no unit is mounted in the opening 24 this must be closed-off from the surrounding water.
This can be made by means of a deep cowl 29, which can be fitted to the reinforced structure 25 by means of bolts 30 accessible from the engine room before the pontoon is first launched, or before a fitted unit is removed later on for overhauling.
The cowl I must not hamper the mounting and dismounting of the unit 18, and it is so wide, that it can receive the portion of unit extending above its mounting flange.
When the thruster unit 18 has been properly mounted the cowl 29 is removed and a rotating mechanism 32, provisional-lye stored beside the opening, is fitted. Finally an electric driving motor is mounted upon the rotating mechanism.
Figure 3 shows, more in detail, a lock chamber 27 per-milting the passage of a lifting line 26.
An opening 33 in the bottom plating outside the big opening 24 for the thruster unit is surrounded by a collar having a mounting flange 34.
The lock chamber 27 comprises a first, rigid tubular member 35, which is formed as a housing for a slide valve member 36 and is provided with flanges for mounting at the flange 34 and for carrying a second, resilient tubular member 37.
The rigid tubular member 35 and the opening 33 enclose a passage, which has a considerable cross sectional area come pared with the diameter of the lifting line 26, so a term-net fitting 46 at the line can pass.
~'2~3~1~
The resilient member 37 comprises a bellows-shaped port lion 38, Moe for instance ox rubber, which permits move-mints in the transverse direction, and is mounted between two flanges 39, 40. These are interconnected by rigid rods 41, which are mounted so as to follow the transverse move-mints of the bellows.
Thy upper flange 40 is provided with an opening, through which the line 26 passes. A sealing sleeve 42 is fitted in this opening, and houses a number of rubber washers 43.
These are split radially so as to permit an easy mounting around the line 26, so an efficient sealing is obtained also along the border zones between the individual strand cores.
In order to prevent the entrance of water into the en-gone room, the lock chamber is connected to a source 44 supplying a gaseous fluid, preferably compressed air, and having a pressure suitable to balance the pressure of the surrounding water. The lock chamber can in this manner be maintained substantially free from water.
In the supply conduit there is a non-return valve 45, which prevents water entering toe supply conduit in case of failure of the supply source.
The embodiment above described and shown in the drawings is an example only of the invention, and the details thereof may be varied in many ways within the scope of the append claims. The means for mounting may be used with various kinds of vessels, and it is evident, that the dismounting of a thruster unit will occur in reverse order, compared to what has been described.
The second resilient member may be shaped in many ways and or instance be composed of a number of annular bellows.
file proselyte inverltioll relates to means for noun-tying a tllrusLer propeller unlit.
offshore vessels, especially those of the semi sub-mersibLe type, are often equipped with thruster propellers, which are rotatable 360 and are used for propulsioll, steer-iffy as well as for positionirlg of the vessel. lounging and dismounl-irlg of these thruster propeller units is a difficult and tickles work.
Us the propeller UllitS are mutilated below tile both Tom platoon of the vessel, the space within the latter, adjacent: to the location of mou-ltjrlg must be separated from the surroulldirlg water. on occasional screening around the operlillcJ, where the propeller Unlit is to be rmoullted, can easily be arranc3ed, but the lines used for performing the terlrlinating part of the lifting of tile unit into the opera-in has hitherto caused many problems.
Usually there is a vertical tube for equal line, which from a hole irk Lowe bottom platirlg, within the vessel, reaches us) to or somewhat above the water level. As the decks of the pontoons carrying the semi submersible vessel during a mountirlg operation will be located just above water level, the space rema:irli-lg for the lifting gear will be rather restricted. Roy required space for the lifting gear must be provided above the deck of the pontoorl, in local-tries needed for other purposes, for instance as bunker or ballast tanks.
'file present inverltion provides efficient means, which do not require much space, for passing a lifting line through the bottom platirlg, and which permits some side ward movement of the line.
. .
Z~338~7 Tile inventioll thus provides means for Insulting a luster propeller unit in an opelli1lg in the bottle struck lure of a vessel end colllpri.sil)g a least two lif.i.nc3 fines, pass.irlc3 out throug11 the bottom plating outside of the opera-S in all beirlg attachable to the thruster propeller Unlit, when the latter has beer brought to a position adjacent to tile opetlillcJ, in which each li.ftinc3 line is passed trackage a plurality ox lock chambers mourlted at the bottle plating, cacti perm:itti.rlg the passage of a lifting lisle and adjacent to tile bottom platirlg including a first, rouges tubular mulberry, ellclos~ g a passage substantially wider tall the cl.iallleter of the liftincJ line, and a second, tubular menlber wtl.i.cll is resili.el-lt at least transversely to the lotting line, said seconc1 member, at its end remote from the bottom pl.at:illcJ, supportincJ a packing sealing around the associated lofting line, end tloistillg means withirl the vessel for operati.llcJ said lines.
lo aft aspect thereof the present inverltic)ll pro-v:Ldes meals Err moulltillt3 a thruster Unlit in an open:irlg in the bottom structure owe a vessel and comprising at least two lotting fines, operable from inside the vessel, passing out throucJtl the bottom platting outside of the operling and being attachable to the thruster propeller unit, when the latter has been brought to a position adjacent to the openillc3, ion Wtl.iCtl each lifting line is passed through a lock chamber at the bottom plating, and adjacent to the latter includes a first, rigid tubular member, enclosing a passage sub Stan-tidally winder than the diameter of the lifting line, as well as a second, tubular member being resiliellt at least transversely to the lifting line resilient tubular member arid :imcludinc3 a bellows-shaped portion, fitted between two flunkies, which are held together by means of a namer of si.dewardly movable, rigid rods, the second tubular member, at its end remote from the bottom plating carrying a pack-inch scaling around the lifting line.
I -I
The lock chamber is preferably corlllected to a Sioux s~pplyillcJ a gaseous fluid at a pressure suited to balallce eye pressure of the surrounding water. 'rho first tubular mulberry is advarltageously formed as the housing for a closure valve.
'rho second, resilient member preferably includes a belk:~ws-shaped portrayal, fitted bitterly two flunkies, WtliCh are Hillel together by meals of a nunlbe.r of sidewardly move able, rouged rods. 'I've upper of the two flanges, throuc3h which the lifting Lyon passes out from the lock challlber, is preferably provided with a sealillg sleeve comprising a nulllber. of split rubber washers.
A cowl operable from withal the vessel and adapted to clockwise the mourlti.rlg openillg is preferably formed arid adapt ted to permit a waterti.cJht fitting of the thruster propeller unlit in the portion of the bottom platincJ surrourlcli.llg the openi.llg durillg a preliminary stage of the mounting opera-twill.
The inverlti.on will below be described with reference to the accompanying drawings, in which:-Figure 1 shows an end view of a semi submersible offshore vessel during the mounting of a thruster propeller Unlit;
Figure 2 shows a cross section through a portion of one of the ponytails owe the vessel; and Figure 3 shows a detail of the lock chamber at the lift line.
, ~2~3~7 Thruster propellers may be used with various types old vessels and Lloatirlg bodies, and the offshore vessel shown - 2b -Jo ~ZV38'7 in Figure 1 is one example only of a possible use. Toe figure illustrates one manner of mounting and dismounting the housing of a thruster propeller unit.
The offshore vessel shown comprises a working platform lo which by means of columns if is carried from two pony loons 12. Upon the plat~orln there is a superstructure 13 providing housing for the staff, and including workshop, stores as Furthermore there is a derrick 14 and a number ox cranes 15, 16, 17.
The vessel is shown in transit position, i.e. the decks of the pontoons 12 are located just above the water level.
Each pontoon 12 is provided with a number of thruster pro-poller units 18, which are located below the bottom plating of the pontoons.
The thruster propeller units are, in the manner better explained in connection with the following figures, mounted in openings in the bottom plating. In the manner indicated in the loft part ox Figure l a thruster propeller unit 18 may be moved by means of wires lo, 20 from the cranes from a position I upon barge, to a position II, and then to a post-lion III directly below the intended opening. From position III the unit is lifted into the opening by meats of lines operable from within the pontoon.
The attachment of these lines and the releasing of the crane wires will require the assistance of divers. Alterna-lively the transfer to position III may occur by means of some displacing carrier, which by divers is guided to the desired position below the opening.
The pontoons 12 will in the conventional manner he pro-voided with ballast tanks, as well as with pumping machinery connectable thereto for deter milling the draft of the pony loons. Furthermore there is an engine room 22 serving each thruster propeller unit.
In Figure 2 the bottom plating of a pontoon is denoted ho 23, and an opening 24 in the plating is surrounded by a reinforced plate structure 25. A flange at the thruster pro-poller unit wow be bolted watertight to this structure.
The final lifting of a unit is brought about by means Jo 3~7 of a number of lifting lines 26, preferably three, even if two only are shown in the (drawing. essay lines are operable from within the engine room 22, and will sealingly pass through the bottom plating by way of lock chambers 27, located outside the opening 24 for the thruster unit.
The lines 26 are connected to lifting gears 28 of arbitrary known type.
Figure 2 shows, in broken Hines a thruster unit 18 hanging in the crane wires 19 and 20, and in full lines just lifted into the opening 24 by means of lie lines 26. When no unit is mounted in the opening 24 this must be closed-off from the surrounding water.
This can be made by means of a deep cowl 29, which can be fitted to the reinforced structure 25 by means of bolts 30 accessible from the engine room before the pontoon is first launched, or before a fitted unit is removed later on for overhauling.
The cowl I must not hamper the mounting and dismounting of the unit 18, and it is so wide, that it can receive the portion of unit extending above its mounting flange.
When the thruster unit 18 has been properly mounted the cowl 29 is removed and a rotating mechanism 32, provisional-lye stored beside the opening, is fitted. Finally an electric driving motor is mounted upon the rotating mechanism.
Figure 3 shows, more in detail, a lock chamber 27 per-milting the passage of a lifting line 26.
An opening 33 in the bottom plating outside the big opening 24 for the thruster unit is surrounded by a collar having a mounting flange 34.
The lock chamber 27 comprises a first, rigid tubular member 35, which is formed as a housing for a slide valve member 36 and is provided with flanges for mounting at the flange 34 and for carrying a second, resilient tubular member 37.
The rigid tubular member 35 and the opening 33 enclose a passage, which has a considerable cross sectional area come pared with the diameter of the lifting line 26, so a term-net fitting 46 at the line can pass.
~'2~3~1~
The resilient member 37 comprises a bellows-shaped port lion 38, Moe for instance ox rubber, which permits move-mints in the transverse direction, and is mounted between two flanges 39, 40. These are interconnected by rigid rods 41, which are mounted so as to follow the transverse move-mints of the bellows.
Thy upper flange 40 is provided with an opening, through which the line 26 passes. A sealing sleeve 42 is fitted in this opening, and houses a number of rubber washers 43.
These are split radially so as to permit an easy mounting around the line 26, so an efficient sealing is obtained also along the border zones between the individual strand cores.
In order to prevent the entrance of water into the en-gone room, the lock chamber is connected to a source 44 supplying a gaseous fluid, preferably compressed air, and having a pressure suitable to balance the pressure of the surrounding water. The lock chamber can in this manner be maintained substantially free from water.
In the supply conduit there is a non-return valve 45, which prevents water entering toe supply conduit in case of failure of the supply source.
The embodiment above described and shown in the drawings is an example only of the invention, and the details thereof may be varied in many ways within the scope of the append claims. The means for mounting may be used with various kinds of vessels, and it is evident, that the dismounting of a thruster unit will occur in reverse order, compared to what has been described.
The second resilient member may be shaped in many ways and or instance be composed of a number of annular bellows.
Claims (9)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. Means for mounting a thruster propeller unit in an opening in the bottom structure of a vessel and com-prising at least two lifiting lines, passing out through the bottom plating outside of the opening and being attachable to the thruster propeller unit, when the latter has been brought to a position adjacent to the opening, in which each lifting line is passed through a plurality of lock chambers mounted at the bottom plating, each permitting the passage of a lifting line and adjacent to the bottom plating inclu-ding a first, rigid tubular member, enclosing a passage substantially wider than the diameter of the lifting line, and a second, tubular member which is resilient at least transversely to the lifting line, said second member, at its end remote from the bottom plating, supporting a packing sealing around the associated lifting line, and hoisting means within the vessel for operating said lines.
2. A means according to claim 1, in which the lock chamber is connected to a source supplying a gaseous fluid at a pressure suited to maintain the lock chamber substantially free from the water surrounding the vessel.
3. means according to claim 2, in which the first tubular member is the housing for a closure valve.
4. A means according to claim 3, in which the second, resilient member includes a bellows-shaped portion, fitted between two flanges, which are held together by means of a plurality of sidewardly movable, rigid rods.
5. A means according to claim 4, in which the upper of the two flanges through which the lifting line passes out from the lock chamber, is provided with a sealing sleeve comprising a plurality of split rubber washers.
6. Means for mounting a thruster unit in an open-ing in the bottom structure of a vessel and comprising at least two lifting lines, operable from inside the vessel, passing out through the bottom plating outside of the open-ing and being attachable to the thruster propeller unit, when the latter has been brought to a position adjacent to the opening in which each lifting line is passed through a lock chamber at the bottom plating, and adjacent to the latter includes a first, rigid tubular member, enclosing a passage substantially wider than the diameter of the lifting line, as well as a second, tubular member being resilient at least transversely to the lifting line resilient tubular member and including a bellows-shaped portion, fitted bet-ween two flanges, which are held together by means of a number of sidewardly movable, rigid rods, the second tubular member, at its end remote from the bottom plating carrying a packing sealing around the lifting line.
7. A means according to claim 6, in which the lock chamber is connected to a source supplying a gaseous fluid at a pressure suited to balance the pressure of the surrounding water.
8. A means according to claim 6, in which the first rigid tubular member is the housing for a closure valve.
9. A means according to claim 7, in which the first rigid tubular member is the housing for a closure valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000449871A CA1220387A (en) | 1984-03-19 | 1984-03-19 | Means for mounting a thruster propeller unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000449871A CA1220387A (en) | 1984-03-19 | 1984-03-19 | Means for mounting a thruster propeller unit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1220387A true CA1220387A (en) | 1987-04-14 |
Family
ID=4127430
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000449871A Expired CA1220387A (en) | 1984-03-19 | 1984-03-19 | Means for mounting a thruster propeller unit |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1220387A (en) |
-
1984
- 1984-03-19 CA CA000449871A patent/CA1220387A/en not_active Expired
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |