US3209717A

US3209717A - Bow manoeuvring jet system for vessels

Info

Publication number: US3209717A
Application number: US259025A
Authority: US
Inventors: George T R Campbell; Norman V Laskey
Original assignee: Algonquin Shipping and Trading Ltd
Current assignee: Algonquin Shipping and Trading Ltd
Priority date: 1962-02-20
Filing date: 1963-02-18
Publication date: 1965-10-05
Anticipated expiration: 1982-10-05
Also published as: GB944640A

Description

Oct. 5, 1965 G. T. R. CAMPBELL ETAL 3,209,717

BOW MANOEUVRING JET SYSTEM FOR VESSELS Filed Feb. 18, 1963 3 Sheets-Sheet l Oct. 5, 1965 G. 'r. R. CAMPBELL ETAL 3,209,717

BOW MANQEUVRING JET SYSTEM FOR VESSELS Filed Feb. 18, 1963 5 Sheets-Sheet 2 Inventors fl- G.T.R. CAMPBELL N.V. LASKEY i z%g j; yi vfr Attorneys Oct. 5, 1965 e. T. R. CAMPBELL ETAL 3,209,717

BOW MANQEUVRING JET SYSTEM FOR VESSELS Filed Feb. 18, 1963 3 Sheets-Sheet 3 Inventors G.T.R. CAMPBELL Attorneys United States Patent 4 69 3 Claims. (Cl. 114-151) This invention relates to bow manoeuvering jet system for vessels and particularly to such systems which can be operatively connected with the steering system of the ship whereby directional control of the vessel is obtained particularly at low speeds directly from the steering wheel when manually controlled or when the vessel is being steered automatically in association with a gyro pilot and steering repeater system.

There have been numerous attempts at providing jet steering for vessels with the aid of a pumping system installed within the vessel. One form makes use of a mixed flow type pump in which the pump draws directly from the sea via a vertical suction pipe or pipes and discharges to transverse jet pipes. A central diverting valve is provided on the discharge side of the pump for the purpose of diverting the discharge from the pump to appropriate jet pipes on either side of the bow of the vessel. The disadvantage of such a system is the appreciable time lag which takes place between the instant the corrective bow thrust is anticipated and the moment when the jet becomes effective. The reason for this is because the pump which is normally run at an idle speed has to be speeded up and it is only when full speed is obtained in the pump that the thrust becomes effective. This time lag will produce excessive hunting in a ships steering system.

This is the prime cause of erratic performance of automatic pilots in heavy weather and can be defined as a type of self-exciting oscillation to which the system is subjected.

A primary object of the present invention is, therefore, to provide a bow steering system which can provide instantaneous thrust of an order of magnitude which can be varied over wide units and must be capable of operating in unison with the rudder and independent of the same when required.

The instantaneous operation of the full designed thrust from the jet nozzle is obtained by introducing a return or recirculating line on the discharge side of the pump. A control valve actuated by a pneumatic governor is installed in this line so that the appropriate quantity of water based on the rated speed of the pump is discharged to the return system while the static discharge head on the pump is maintained constant at all times. The control valve eifects a throttling process so that the pressure in the return line after passing the control valve is reduced to a value at which it can be introduced into the suction piping or trunking without undue turbulence. Alternatively, the pressure drop can be regulated to a value which would result in a very slight pressure head differential between the water in the return line and the hydrostatic pressure at a discharge point suitably located on the shell of the vessel at a level below the water line.

The bow manoeuvering system about to be described is simple and inexpensive and can be installed very readily in existing vessels as Well as in new construction. In addition to affording a vessel directional stability under all conditions of operation, the pump used for producing the jet can be used for ballasting and deballasting the vessel. It is only necessary to connect the suction eye of the bow jet pump to the main ballast lines.

With the return loop in the system and the control valve in association with a pneumatic governor used positioning and controlling the return flow and consequently the discharge pressure maintained in the system, the pump can be run at constant speed concomitant with a steady load on the prime mover driving the pump. The prime mover can be a reciprocating steam engine, steam turbine, gas turbine, diesel engine or electric motor. As the speed and power output of the prime mover used to drive the bow jet pump is constant, a difficult problem of speed and power control is solved in a very simple manner.

These and other objects of the invention will be apparent from the following detailed description and the accompanying drawings, in which:

FIG. 1 is a plan view of a portion of the bow section of a ship at approximately the tank-top level showing the bow jet steering inlet and discharge arrangement and the necessary control valves.

FIG. 2 is an elevation partly in section of the bow jet steering arrangement shown in FIG. 1.

FIG. 3 is an enlarged vertical section of the bow jet nozzle attached to the inner wall of a ships side.

FIG. 4 is a schematic layout of the bow jet steering system showing the electric and pneumatic controls for the system tied in with the vessels rudder; and 4a is the control panel.

FIGS. 5 and 6 are schematic layouts of the bow jet steering system tied in with the vessels rudder and using the vessels fluid cargo loading and unloading pump and storage system for operation of the jet steering system.

FIG. 7 is an enlarged plan view of the vessels pumping and distribution system shown in FIG. 5.

FIG. 8 is a transverse vertical section through a vessels hull showing the jet nozzle feed and discharge.-

Referring to the drawings, the invention is best illustrated in FIGS. 1 and 2. A schematic outline of the bow jet steering system complete with its electric and pneumatic controls, tied in with the steering rudder of the ship is shown on FIGURE 4.

The system consists of a vertical or a horizontal double suction centrifugal pump 5, driven by a suitable electric motor 6 or other suitable form of prime mover. The suction side of the pump 5 is connected, through the pipe 8 and expansion member 9 with the pump suction trunk 10, suitably located above the cellular double bottom of a ship 11 or if necessary within the double bottom. The trunk 10 is in direct communication with the sea via the port and

starboard valves

12 and 12A and the

sea inlet pipes

13 and 13A.

A branch connection 14 is fitted to the discharge side of the pump 5 and a discharge branch fitting 15 having a bifurcated configuration is secured to the connection 14 in direct alignment With the pump discharge. Two discharge pipes 16 are connected, at one end through the expansion members 17 with the discharge branch fitting 15. The opposite ends of the discharge pipes 16 are connected to the port and

starboard butterfly valves

18 and 18A, which, in turn, are connected to the port and

starboard discharge nozzles

19 and 19A. Each of these

valves

18 and 18A are operated by pneumatic actuators 20 via linkage 21.

The jet nozzle plates 22 (see FIG. 3) of the

discharge nozzles

19 and 19A are preferably machined out of solid stainless steel forgings and the configuration of the plates 22 are designed to suit the thrust requirements of the vessel.

As the design objective of the present bow jet steering system is to provide an instantaneous thrust at either of the port or

starboard nozzles

19 or 19A when required, the system has been arranged so that an artificial head is always maintained on the discharge side of the pump. This is achieved by connecting a return loop pipe 23 to 3 the branch 24 of the fitting 14 and leading back to the suction trunk 10 or directly overboard if deemed necessary. This pipe 23 is fitted with a control valve 25 and an expansion member 26.

The control valve 25 is operated by a pneumatic governor/ actuator 27 via the linkage 28.

The full rated head of the pump is maintained in the discharge pipes 16 at all times so that immediate response of jet thrust from either one or other of the

discharge nozzles

19 or 19A will result at the instant either one or the other of the

valves

18 or 18A are opened. The control valve 25 in the return loop pipe 23 will close concurrently with the opening of one or other of the

valves

18 or 18A so that the entire discharge from the pump 5 will be diverted to the

selected jet nozzle

19 or 19A.

The control system (see FIG. 4) incorporates electrically operated

solenoid valves

29 and 29A for controlling the fiow of compressed air to the pneumatic actuators 20 for the

valves

18 and 18A.

The thrust from either of the nozzles 22 can be varied over a wide range remotely from the control console 30 located in the wheel house or at any other convenient location of the vessel. On this console 30 a remote air loading panel 31 provides a pneumatic signal which is transmitted to the pressure pilot 32 located in the vicinity of the pneumatic governor-actuator 27. The pressure pilot 32 controls the stroking of the actuator 27 and, by varying the amount of water returned from the discharge side of the pump 5 to the suction trunk or directly to the sea between zero and 50% of the total flow, the thrust from the nozzles 22 can be appropriately varied.

An air accumulator 33 receives a supply of compressed air from the compressor 34 or other appropriate source of supply, through the reducing valve 35. The compressed air from the accumulator 33 is fed through the pipe 36 and

branch pipes

36A and 36B to the solenoid operated

valves

29 and 29A and thence to the actuators 20. The exhaust of air from the actuators is carried off by the lines 36C.

Compressed air from the accumulator 33 is also fed through the reducing valve 37 and pipe 38 to the pressure control panel 31, mounted on the control console 30, and from the remote on loading panel 31 the compressed air is fed through the pipe 39 to the control pilot 32. From the control pilot 32, compressed air is directed through either of the lines 40 or 41 to one or other side of the pneumatic governor/actuator 27 for appropriate movement of the actuator to effect a controlled opening or closing of the valve in the return loop between the pump 5 and the suction trunk 10.

The solenoid operated valves-29 and 29A are controlled either automatically or manually from the control console 30. For automatic control, a source of electric current 42 supplies current to the center position of the double throw switch 43 which is operated by a spring loaded pivoted arm 44, pivoted about the fulcrum 43A, the spring normally holding the arm in the mid or neutral position of the switch. The pivoted arm 44 terminates in a roller 44A which is in contact with a pair of adjustable

cam profile plates

45 and 46 mounted on a quadrant plate 47 attached to an extension 48 of the ships rudder stock.

In service, the angular position of the

cam profile plates

45 and 46 can be set at the most suitable angle, depending on the condition of wind and sea, so that the thrust of the bow jet will assist the rudder in providing a course correcting torque after the rudder has passed through a selected angle and thereby reduce the amount of helm required by the rudder. A switch 48A controlled by a push button 48B on the panel controls the flow of current to the double throw switch 43 and to each of the

solenoid valves

29 and 29A through the

lines

49 and 50 and the

return lines

51 and 52 from the electric solenoid valves are connected to opposite sides of the double throw switch 43.

For manual control of the

solenoid valves

29 and 29A, a switch 53 in the line 51 and operated by the push button 54 on the console 30 controls the solenoid valve 29, while a switch 55 in the line 52 and operated by the push button 56 controls the solenoid operated valve 29A. Indicating lights 57 provide on and off indication for the port solenoid valve 29, while the indicating lights 58 provide on and off indication for the starboard solenoid valve 29A.

The power supply to the pump motor 6 is by a separate supply, not shown, and is controlled by the stop/start push buttons 59.

An air pressure gauge 60 provides an indication of air supply pressure while the air pressure gauge 61 indicates the pressure in the line leading to the pressure control panel 31 and control pilot 32.

The above described installation of bow jet steering is applicable to most types of ships. However, a considerable saving in capital cost can be obtained in tanker type vessels where loading and unloading pump equipment is available at all times except when the vessel is stationary and loading and unloading operations are being carried out. This means that when such a vessel is underway such pump equipment is normally not in use and is available for the purpose of supplying bow jet steering in the manner above described. The use of loading and unloading pump equipment is hereinafter described and is illustrated in FIGS. 5, 6, 7 and 8.

In this particular application of the invention, the loading and unloading pumps 62 are shown in FIG. 7 and are each connected on one side with pipe lines 63 leading to the deck valves 64. The other side of the pumps are connected to the ships cargo tanks by the pipe lines 65. Suitable valves 74 are installed in all of the pipe lines 65 of the pumps 62 in accordance with standard tanker practice.

At suitable locations, as near the pumps 62 as possible, port and

starboard sea chests

66 and 67 respectively, are fitted on the ships side.

Pipe connections

68 and 69 connect the

sea chests

66 and 67 with each of the pumps 62 on the side of the pumps to which the pipe lines 65 are connected.

Main valves

70 and 71 are fitted at the

sea chests

66 and 67 and individual valves 72 are fitted in the

lines

68 and 79 between each of the pumps 62.

The pumps 62 and the

sea chests

66 and 67 are isolated from the

cargo distribution lines

63 and 65 by the

valves

73 and 74. This arrangement is standardized layout of a pump room in a modern tanker.

When it is desired to utilize the pumps 62 for bow jet steering, the valves 73 between the pumps 62 and the lines 63 are opened and the deck valves 64 are closed. The lines 63 are extended beyond the

deck valves

64 and 75 and are then merged into a single line 76 which is directed downwards into the forward pump room of the tanker in which the bow jet piping and port and starboard nozzles 190 and 190A are located (see FIGURE 6).

A branch fitting 77 is fitted to the end of the line 76, and a bifurcated fitting 78 is fitted to one of the branches of the fitting 77. Pipes connect between one branch of the bifurcated fitting 78 and the port and starboard butterfly valves and 180A fitted to the inboard side of the

jet nozzles

220 and 220A.

A pipe 79 connects the other branch of the fitting 77 with the butterfly valve 250 which is in communication with the sea by means of the short pipe 80.

The valves ISGJSGA, jet nozzles l90190A and valve 250 above described and illustrated in FIGS. 6 and 8 perform the equivalent functions as do the valves 18-18A, jet nozzles 19-19A, and valve 25 illustrated in FIG. 4.

The pneumatic and electrical controls of the valves 180-180A and the valve 250 are exactly the same as is described and illustrated in FIG. 4 and have been numbered similarly.

In the operation of this invention whereby an instantaneous trust is obtained to either port or starboard to assist the steering operation, the operation can be carried out either automatically or manually by merely setting the correct push buttons on the panel console 30. Manual operation would normally be resorted to when the vessel is being manoeuvred in confined waters such as in docking. At all other times, the system can be set to operate automatically.

Assuming that the system is set to operate automatically and the switch 48A has been closed. The pump 5 is in constant operation with the

valves

12 and 12A open to permit sea water to enter the pump 5. Air pressure is maintained in the accumulator 33 and in the

pipes

36, 36A and 36B. Any movement of the quadrant 47 in one direction or the other will operate the switch 43 and cause either of the

solenoid valves

29 and 29A to open depending upon the direction in which the quadrant 47 is moved. Assuming that it is the port solenoid valve 29 which has been energized, it will immediately cause the actuator 20 to move the valve 18 towards the open position. Simultaneously, the valve 25 will be moved towards the closed position, and the sea water discharge of the pump 5 will be diverted through the valve 18 and through the jet nozzle 19. The thrust from the nozzle 19 can be varied over a wide range by control of the valve 25. This control of the valve 25 is carried out remotely by the pilot adjusting the air loading panel 31 to provide a pneumatic signal which is transmitted to the pneumatic governor/positioner 27 which in turn controls the valve actuator 28. Adjustment of the opening of the valve 25 varies the amount of water returned to the sea and the thrust at the nozzle 19 is varied accordingly.

As the quadrant 47 is actuated in one direction or another, simultaneous opening and closing of one or other of the port or

starboard valves

18 or 18A will take place so that a thrust at either of the nozzles 22 or 22A will immediately assist the action of the ships rudder in providing a correction of the ships course.

With the ships automatic pilot in operation, the master gyro which initiates the signal for the necessary amount of course correction will provide very close directional stability and the dead bands incorporated in the steering gear mechanism of the vessel, which are normally effective to prevent hunting of rudder control over a limited range, can therefore be eliminated from the controls provided for the automatic pilot. With the close directional stability provided by the thrust at the

jet nozzles

19 and 19A, the amount of correction to be provided by the rudder can be reduced considerably. This reduction in rudder movement together with the instant application of thrust at the

nozzles

19 or 19A is of particular advantage in maintaining ships such as weather ships and cable laying ships on course or a fixed position in rough weather, particularly if the ships have to maintain a fixed position or proceed at slow speed.

Immediate changeover from automatic to manual control is achieved at the console 30. The pilot can then control the opening and closing of the

valves

18 and 18A by operating the appropriate switches 53 and 55 by the push buttons 54 and 56.

The operation of the system illustrated in FIGS. 5, 6, 7 and 8 is exactly the same as that above described with the exception that the deck valves 64 and the cargo distribution valves 74 are kept closed, and the sea chest valves and 71 are opened. One or all of the cargo pumps 62 are then operated to maintain a constant head of sea water in the

pipes

63, 75 and 76. When the

valves

180 and 180A are closed, the valve 250 is opened permitting the pump discharge to be exhausted to the sea through the pipe 80. However, when either of the

valves

180 or 180A are moved to the open position, the valve 250 is correspondingly moved towards the closed position permitting the full discharge of the pump or pumps 62 to be diverted to the jet nozzle whose corresponding valve is open.

What we claim is:

1. A bow manoeuvring jet system for ships comprising pump means, the said pump mean-s having its suction side connected to sea water, port and starboard jet nozzles, a valve associated with each of said nozzles, a pipe connection between the discharge side of said pump means and said valves, a by-pass connection between the discharge side of said pump means and its suction side, a control valve in said by-pass connection, pneumatic actuator means associated with each of said valves, the said actuator means associated with said control valve operating to close the said control valve when either of the said valves associated with the said nozzles are opened, a solenoid operated control valve associated with each of said actuators operating the said nozzles, the said latter control valve controlling the flow of air to the said actuators, a pressure control member associated with the said by-pass control valve, the said pressure control member controlling the degree of opening of the said control valve in relation to the degree of opening of the valves associated with the said nozzles, a ships steering mechanism, switch means associated with said steering mechanism, the said switch means controlling the said actuating means actuating the said valves associated with the said nozzles, said switch means effecting opening or closing of one or other of said latter mentioned valves in agreement with the movement of said steering mechanism.

2. In a jet system as set forth in claim 1 in which the switch means associated with the ships steering means for individually controlling the opening and closing of the valves associated with the said nozzles includes a cam mechanism secured to the ships steering means and a double throw switch operated by the said cam mechanism.

3. In a jet system as set forth in claim 1 in which the means associated with the ships steering means for individually actuating the said valves includes a cam mech anism secured to the ships steering means and a double throw switch operated by the said cam mechanism.

References Cited by the Examiner UNITED STATES PATENTS 410,181 9/89 Ongley 91-461 X 2,276,193 3/42 Hanley 114-151 X 2,786,420 3/57 Kenney 103-97 3,078,661 2/63 Spence 12 3,105,453 10/63 Hayes 114144 3,121,994 2/64 Aldropp 115-12 X MILTON BUCHLER, Primary Examiner. ANDREW H. FARRELL, Examiner.

Claims

1. A BOW MANOEUVRING JET SYSTEM FOR SHIPS COMPRISING PUMP MEANS, THE SAID PUMP MEANS HAVING ITS SUCTION SIDE CONNECTED TO SEA WATER, PORT AND STARBOARD JET NOZZLES, A VALVE ASSOCIATED WITH EACH OF SAID NOZZLES, A PIPE CONNECTION BETWEEN THE DISCHARGE SIDE OF SAID PUMP MEANS AND SAID VALVES, A BY-PASS CONNECTION BETWEEN THE DISCHARGE SIDE OF SAID PUMP MEANS AND ITS SUCTION SIDE, A CONTROL VALVE IN SAID BY-PASS CONNECTION, PNEUMATIC ACTUATOR MEANS ASSOCIATED WITH EACH OF SAID VALVES, THE SAID ACTUATOR MEANS ASSOCIATED WITH SAID CONTROL VALVE OPERATING TO CLOSE THE SAID CONTROL VALVE WHEN EITHER OF THE SAID VALVES ASSOCIATED WITH THE NOZZLES ARE OPENED, A SOLENOID OPERATED CONTROL VALVE ASSOCIATED WITH EACH OF SAID ACTUATORS OPERATING THE SAID NOZZLES, THE SAID LATTER CONTROL VALVE CONTROLLINGG THE FLOW OF AIR TO THE SAID ACTUATORS, A PRESSURE CONTROL MEMBER ASSOCIATED WITH THE SAID BY-PASS CONTROL VALVE, THE SAID PRESSURE CONTROL MEMBER CONTROLLING THE DEGREE OF OPENING OF THE SAID CONTROL VALVE IN RELATION TO THE DEGREE OF OPENING OF THE VALVES ASSOCIATED WITH THE NOZZLES, A SHIP''S STEERING MECHANISM, SWITCH MEANS ASSOCIATED WITH SAID STEERING MECHANISM, THE SAID SWITCH MEANS CONTROLLING THE SAID ACTUATING MEANS ACTUATING THE SAID VALVES ASSOCIATED WITH THE SAID NOZZLES, SAID SWITCH MEANS EFFECTING OPENING OR CLOSING OF ONE OR OTHER OF SAID LATTER MENTIONED VALVES IN AGREEMENT WITH THE MOVEMENT OF SAID STEERING MECHANISM.