WO1991016150A1

WO1991016150A1 - Cleaning equipment, especially for the cleaning of a tank

Info

Publication number: WO1991016150A1
Application number: PCT/DK1991/000110
Authority: WO
Inventors: Erik Lund Jepsen; Flemming Hansen
Original assignee: Toftejorg A/S
Priority date: 1990-04-25
Filing date: 1991-04-24
Publication date: 1991-10-31
Also published as: DK102390A; DK102390D0

Abstract

Tank cleaning equipment (20) according to the invention is mounted in a housing (18) over the opening (26) to a tank (5) and having a valve (16, 17) for the closing of the opening (26). Inside the housing (18) there is suspended a cleaning head (1) with movable nozzles (2) which are connected to a telescopic supply pipe (3) or an extendable hose (4) through which cleaning fluid under pressure can be conveyed to the nozzles (2). The extending of the fluid supply pipe (3, 4) is controlled by a drum drive (10) with a wire (7) which, over rollers (9), is connected (8) to the cleaning head (1), whereby the whole of the cleaning aggregate can be lowered into the tank (5) and housed completely in the housing (18) when cleaning is not being carried out. The equipement can thus be made very compact and is hereby well suited for permanent mounting on tanks, e.g. on tanker vessels, and the operation can be made automatic and independant of manual control and handling. This results in a more safe and environment-friendly cleaning as compared with the hitherto-known stationary installations in tanks.

Description

CLEANING EQUIPMENT, ESPECIALLY FOR THE CLEANING OF A TANK

The invention relates to cleaning equipment, especially for the cleaning of a tank, and comprising a cleaning head with movable nozzles which is mounted on a fluid supply pipe which can be introduced into the interior of the tank and through which fluid can be supplied from a pump placed out¬ side the tank, so that the fluid flowing from the nozzles during cleaning can spray the whole of the internal surface of the tank, after which the cleaning head is withdrawn completely out of the tank.

Equipment of this kind is used for the cleaning of tank in- teriors and similar enclosed spaces when these are empty of contents. These tanks can be stationary, mobile or sea¬ going tanks which have to be cleaned in order to be able to function according to their purpose.

Both permanently-installed as well as transportable clean¬ ing equipment is known for the cleaning of such tanks.

The disadvantages with the permanent installations are that the cleaning head, the supply pipe and support arms easily become so soiled that it can be difficult to get the equip¬ ment to function satisfactorily. Moreover, such installa¬ tions can suffer damage from being in a permanently im¬ mersed state.

The application possibilities of the transportable equip¬ ment are limited to the cleaning of open tanks, which can give rise to environmental dangers in the event of leakage, and in special cases there can arise further dangers of ex¬ plosive mixtures. Furthermore, in such cases a pre-washing cannot be carried out in accordance with the valid norms, the reason being that the tank cannot be closed during the cleaning .

It is the object of the invention to overcome the many drawbacks and disadvantages inherent in the known cleaning equipment, and this is achieved with equipment which has a fluid supply pipe configured as telescopically-extendable pipe sections which are mounted on the outside of the tank in a housing in which the pipe sections and the cleaning head can be kept when the cleaning head has been drawn out of the tank.

The equipment achieved hereby is first and foremost com¬ pact, in that the pipe does not take up much space in its telescoped state, whereby the height of the construction can be considerably reduced. The equipment can thus be used for permanent mounting, especially on tanker vessels, and enable cleaning to take place by means of suitable automa¬ tics, thus rendering the cleaning operation independent of time and place. A standard of cleaning of a hitherto un- known high class can thus be achieved by relatively simple means which are light in weight and require neither qual¬ ified supervision nor operation, and which do not occupy much space.

Moreover, the pipes can be made mutually unturnable, where¬ by the cleaning process can be completely controlled in that the cleaning head can be secured unturnably on the supply pipe. The cleaning programme is hereby uniform, and therefore the cleaning is always the best possible.

By configuring the supply as a flexible hose as disclosed in claim 2, it will be possible to introduce a considerable length of hose and hereby clean deeper tanks, and the weight of the equipment will remain relatively low.

By mounting the telescopic pipes on the top of the tank as disclosed in claim 3, the weight of the cleaning head will draw the pipes out to the desired depth, after which a wire winch can easily lift the head and withdraw it from the tank together with the pipes.

By mounting a drive wire both on the cleaning head and in the hose drum as disclosed in claim 4, the insertion of the cleaning head can be effected in a very practical manner, and the withdrawal will be correspondingly simple.

Finally, as disclosed in claim 5, it is expedient to mount a valve between the cleaning equipment and the tank, and to provide drain holes in the housing in which the cleaning head is kept after withdrawal from the tank. This enables the access for the cleaning head to be completely closed off, and also ensures that the residual fluid in the clean¬ ing head and supply pipe is led away from the housing and does not risk running back into the inside of the tank at the next cleaning.

The invention will now be described in more detail with reference to the drawing, where

fig. 1 is a schematic drawing showing equipment for the cleaning of a single tank seen from above,

fig. 2 is a schematic drawing showing corresponding equipment for the cleaning of several tanks seen from above,

fig. 3 shows equipment with a telescopic supply pipe withdrawn from the tank, seen from the side and partly in section,

fig. 4 shows this equipment seen in the direction IV-IV in fig. 3, fig. 5 shows equipment with a supply hose withdrawn from the tank, seen from the side and partly in sec¬ tion, and

fig. 6 shows this equipment seen from the rear.

Two examples of the use of the cleaning plant are shown schematically in figs. 1 and 2.

The actual equipment 20 is seen from above mounted at a suitable place on the top of a tank 5 which is indicated in the drawing by the stippled line, which on a ship would normally be on the deck 6, as shown in figs. 3, 5 and 6.

The individual items of equipment 20 are via a valve 21 connected to a permanently-mounted fluid pipe 19 which functions as supply pipe for the cleaning fluid under pres¬ sure, and which is connected in a commonly-known manner to a pump 22.

The cleaning of the tank interior can be carried out by suitable control of the valves 21. Where the need exists, an automatic and programmable cleaning can be established in such a manner that it is effected at the desired inter¬ vals and with the desired degree of efficiency. This is of great importance, especially on tanker vessels, and this can be carried out with the cleaning equipment which can work even in relatively hard weather with corresponding seas. The otherwise necessary changes in course and pos¬ sibly lying to are hereby avoided, whereby the capacity of the tanker is utilized to the optimum.

At the same time, the cleaning can be effected without man- ual operation, which is made possible by the configuration of the actual cleaning unit, which will now be described in more detail .

In figs. 3 and 4 is shown an example of an embodiment com¬ prising an outer housing 18 in the form of a length of pipe which is welded to the deck 6 over the hole 26 which leads to the interior 5 of the tank.

At the bottom of the housing 18 there is a built-in slide valve 16, the valve element of which can be inserted as in- dicated by the stippled line, and hereby completely shut off the tank 5 from the atmosphere.

At the top of the housing 18 there is internally secured a telescope housing 23 which encloses a number of mutually associated pipes 3, see fig. 4, the inner pipe of which is secured to the actual cleaning head 1 which is located under the pipes.

Moreover, at the top there is access for the pressure fluid through an inlet pipe 19 with flange and access 25. When pressure fluid is supplied, this will partly extend the telescopic pipes 3 and hereafter start the cleaning head's nozzles 2.

For the control of the lowering and also of the raising of the cleaning head 1, one or more steel wires 7 are mounted to the head in a pair of fastenings 8, said wires running over wheels 9 at the side of the telescope housing 23. The wire 7 is finally led over a winch drum 10 which can be turned by a motor 11 or possibly manually by means of a handle (not shown).

When a tank is to be cleaned, the equipment is in the posi¬ tion shown in figs. 3 and 4 with the valves 16, 17 closed and the supply valve 21 shut off. Hereafter, the valves 16, 17 are opened and the motor 11 is started. The cleaning head 1 is lowered successively with the inlet pipes 3 until the cleaning head 1 is in its start position, where fluid is supplied through the pipes 3 to the cleaning head 1 by the opening of the supply valve 21. The nozzles 2 on the cleaning head inject the cleaning fluid into the interior of the tank in such a manner that the whole inside surface of the tank is sprayed in ac¬ cordance with a certain pattern, controlled partly by the cleaning head and partly by its position at the height which is controlled by the winch 10.

When the cleaning is complete, the inlet 25 to the head ^'1 is cut off, and the head is raised to the -starting posi- tion, after which the valve 17 cuts off the supply to the tank 5.

Above the valve 16, 17 in the housing 18 there is one or more drain holes 24 through which cleaning fluid from the cleaning equipment can be led away. These drain holes 24 can be provided with a not-shown closing arrangement, pre¬ ferably by means of a valve, so that the holes can be com¬ pletely blocked off from the surroundings when the valve 16, 17 is open. The movable parts of the cleaning equipment hereby form part of the inside of the housing 18, which is an advantage from the point of view of security.

Upon the closing of the valve 16, 17 when the cleaning equipment is withdrawn from the tank, the drain holes 24 must be opened again in order for the fluid to be led away from the inside of the housing. This is a prerequisite for enabling the cleaning process to be automated, in that it must be ensured that drain fluid from the cleaning equip¬ ment cannot run back into the tank 5.

The equipment is hereafter ready for the next cleaning op- eration in the tank, and corresponding equipment mounted on adjacent tanks can clean these in a corresponding manner.

In figs. 5 and 6 is shown a second embodiment in which the supply pipe is replaced by a flexible hose 4 which is in¬ serted from above through an opening in the top of the housing 18. The end of the hose is secured to the cleaning head 1 and runs in an arc over a number of guide rollers 9 to a drum 12 on which the rest of the hose is wound. The supply to the end of the hose is effected in a known manner through an inlet 25 in the side of the drum.

For the winding-out and winding-in of the hose 4, -a winch with a drum 10 is mounted which is driven by a motor 11, and on which there is wound one or more steel wires 7 which over the rollers 9 are secured to the cleaning head 1 at fastening points 8.

Moreover, on the drum axle there is mounted a wheel 14 with a drive 13 to a drivewheel 15 on the drum axle. When the motor 11 turns the winch, the hose 4 will be unwound so that the cleaning head is lowered into the tank 5, and con¬ versely the hose will be wound up on the drum and withdrawn from the tank.

This embodiment has the advantage that a cleaning head can be introduced to relatively great depths and with a reason¬ ably good stability. Where this is desired to be improved, a special hose or holster will be able to be used which by fluid pressure provides necessary stiffening by distension of channels in the side in a commonly-known manner.

Similarly, this embodiment will be able to be automated, whereby the possibility is provided of a high standard of cleaning in a safe, environment-friendly and labour-saving manner.

Claims

C A I M S

1. Cleaning equipment, especially for the cleaning of a tank, and comprising a cleaning head provided with movable nozzles which is mounted on a fluid supply pipe which can be introduced into the tank, and through which fluid can be supplied from a pump placed outside the tank so that fluid ejected from the nozzles during the cleaning can spray the whole of the interior of the tank, after which the cleaning head is withdrawn completely from the tank, c h a r a c ¬ t e r i z e d in that the fluid supply pipe is configured as telescopically extendable pipe sections (3) which are mounted in a housing (18) on the outside of the tank (5) in which the pipe sections (3) and the cleaning head (1,2) can be kept when the cleaning head (1,2) is withdrawn from the tank (5) .

2. Cleaning equipment according to claim 1, c h a r a c ¬ t e r i z e d in that the fluid supply pipe is configured as a flexible hose (4) which is wound on a hose drum (12) mounted on the outside of the tank (5) in a housing (18) in which the cleaning head (1,2) can be kept in rolled-back position.

3. Cleaning equipment according to claim 1, c h a r a c ¬ t e r i z e d in that the pipe sections (3) are mounted on the top (6) of the tank (5), and in that the cleaning head (1,2) is connected to a wire drive (7,8,9,10,11) for the lowering and raising of the cleaning head (1,2).

4. Cleaning equipment according to claims 1 and 2, c h a r a c t e r i z e d in that the hose drum (12) is connected to a drive (13,14,15), and in that the cleaning head (1,2) is connected to a cooperating wire drive (7,8,9,10,11) for the introduction and withdrawal of the cleaning head (1,2) from the tank (5).

5. Cleaning equipment according to claims 1-4, c h a r ¬ a c t e r i z e d in that the cleaning head (1,2) and the fluid supply pipe (3,4) are separated from the tank (5) by means of a slide valve (16,17) mounted at the bottom of the housing (18) and with drain holes (24) in the housing above the valve (16,17).