WO1998026981A1

WO1998026981A1 - A device for safety- and fire-extinguishing installation on a helicopter platform

Info

Publication number: WO1998026981A1
Application number: PCT/NO1997/000334
Authority: WO
Inventors: Magnus Birkeland
Original assignee: Magnus Birkeland
Priority date: 1996-12-16
Filing date: 1997-12-12
Publication date: 1998-06-25
Also published as: NO965405L; NO965405D0; AU7737698A; NO304509B1; GB2334441A; GB9913585D0; GB2334441B

Abstract

A safety and fire-extinguishing system assembly on a helicopter deck (1), preferably on offshore installation or ships, of the type which is designed as a polygon divided into a number of sectors (2) and having pressurised water supply for flooding the deck surface in order to remove and, if necessary, extinguish burning fuel on the deck surface in connection with a possible helicopter accident, and having a gutter (3) running along the periphery of the polygon for receiving flooding water and any fuel it may wash with it, and having a grating system (4) provided at a distance above the deck surface, and having a plurality of liquid distribution pipes (6) running towards the centre of the deck from a feed pipe (5) extending along the periphery of the deck, and which vary in length and decrease in number in relation to the decreasing width of the deck sector (2) in question, and with liquid distribution outlets (7) preferably distributed at regular intervals, the liquid distribution pipes (6) being supplied from a compression pump via a feed line having adjustable throttle means incorporated therein.

Description

A DEVICE FOR SAFETY- AND FIRE EXTINGUISHING INSTALLATION ON A HELICOPTER PLATFORM

The present invention relates to a safety and fire extinguishing system assembly on a helicopter deck, preferably on offshore installations or ships.

The assembly is used in connection with the type of helicopter deck that is designed as a polygon divided into a number of sectors and having a gutter running along the periphery of the polygon, and having a grating system provided at a distance above the deck surface.

Helicopter decks equipped with fire extinguishing systems of the above-mentioned type are previously known from NO 146 532-B and 148 328-B, both in the name of the present inventor.

The principle on which the systems on the helicopter decks are based according to the previous patents is to remove burning or combustible fluid from areas below and around a crash-landed helicopter and to conduct this fluid out to the peripheral areas of the helicopter deck.

This is achieved in the known patents in that water is introduced through water discharge openings in the centre of the helicopter deck and that the water then flows freely in all directions and down into a collecting channel extending around the periphery of the helicopter deck and having outflow pipes.

When water is supplied through the central openings, it will flow freely to all edges and take with it any burning or combustible fluid away from the central deck area and out into the collecting channel.

Tests have shown that fuel, e.g., jet fuel, which floats on water and which is still burning when it reaches the channel, will rapidly be extinguished when it runs together with the extinguishing or flooding water down into the outflow pipe from the collecting channel.

This relatively rapid extinguishing is a consequence of oxygen starvation. Water having a low temperature will be capable of preventing vaporisation from the leaked fuel and as long as vaporisation and thus gas generation is prevented or kept to a minimum on account of the low temperature, the chance of ignition will be small. Furthermore, reference will also be made to NO 176 509-B, also in the present inventor's name. This patent describes a water supply means for a fire extinguishing system of the type described above where a recirculation cycle is used which comprises a water storage vessel in the form of a tank and a recirculation pump, inserted between the outlets employed and the water discharge openings for the supply of water, and wherein there are incoφorated facilities for separating fuel carried by the water, in order to reduce thereby the consumption of water and reduce the water supply capacity requirements for a possible pressurised water system.

In all the Norwegian patents referred to above, the water is conveyed to the helicopter deck by means of feed lines from the periphery to the central area where one or more water discharge openings are provided.

It has been found that this gives relatively high excess height of water centrally without any full guarantee that when it flows towards the periphery of the deck the water will actually flood all areas of the deck adequately.

The helicopter deck is usually divided into sectors, but this does not give full guarantee of complete flooding either.

The object of the present invention is to remedy this defect and also to improve the facility for de-icing in cold climatic conditions without thereby having to resort to costly systems or investments.

In simple terms, the principle of the present invention is based on feeding water through several distribution pipes running from the periphery of each sector and providing several fluid distribution outlets along the length of all the pipes in order to cover essentially the whole area of each deck sector simultaneously.

Accordingly, the present invention relates to a safety and fire extinguishing system assembly for a helicopter deck, preferably on offshore installations or ships, of the type which is designed as a polygon divided into a number of sectors having a supply of pressurised water for flooding the deck surface in order to wash away and, if necessary, extinguish any burning fuel on the deck surface in connection with a possible helicopter accident, and having a gutter running along the periphery of the polygon for receiving flooding water and any fuel it may wash with it, and having a grating system provided at a distance above the deck surface. The invention is characterised by a plurality of liquid distribution pipes running towards the centre of the deck from a feed pipe extending along the periphery of the deck, and which vary in length and decrease in number in relation to the decreasing width of the deck sector in question, and with liquid distribution outlets preferably distributed at regular intervals, the liquid distribution pipes being fed from a compression pump via a feed line with adjustable throttle means incorporated.

The invention will be described in more detail with reference to the accompanying drawings, wherein:

Fig. 1 shows a helicopter landing deck of conventional design, divided into eight sectors;.

Fig. 2 shows one sector of a deck with a possible distribution pipe configuration according to the invention; - Fig. 2a shows a detail of the discharge outlets of the distribution pipes; and

Fig. 3 shows on a larger scale a detail at the peripheral area of the helicopter deck.

The helicopter deck 1 in Figure 1 is generally polygonal in shape, shown here in the most preferred form, namely built up of eight sectors 2 forming an octagon.

Figure 2 shows a possible configuration of the liquid distribution pipes.

In general, the sector is triangular in shape with base line 5 and side edges 8.

In the illustrated embodiment the base line consists of a feed pipe 5 for liquid, preferably pure water under pressure.

With a view to safety, it is an advantage if the feed pipe 5 in each sector is supplied separately from a non-illustrated source of liquid under pressure.

A plurality of liquid distribution pipes 6 branch off from the feed pipe 5.

The liquid distribution pipes 6 are of varying lengths so that the number of liquid distribution pipes along a line parallel to the base line, represented by the feed pipe 5, is essentially the same. Thus, in the illustrated embodiment there are shown four short pipes 6a, two slightly longer pipes 6b, two even longer pipes 6c and a central long pipe 6d.

The distribution pipes 6 are preferably symmetrically distributed.

The liquid distribution pipes 6 are equipped with discharge outlets 7, such that at the end of each pipe 6 there is an outlet, but also so that there are provided discharge outlets, preferably evenly distributed along the length of the pipes.

These outlets are shown in greater detail in Figure 2a where the end of a liquid distribution pipe 6 is indicated at 9 and where 10 is used to denote a cap or hood for turning the liquid flow in the direction of the deck periphery as is indicated by the arrow (P).

In the case of discharge outlets which are provided on a continuous pipe it is conceivable that the cap 10 is simply made in the form of wings 11 having an overlying cover 12 for turning and directing the liquid flow downwards towards the deck and in the direction of the periphery.

Figure 3 shows a detail of the peripheral area of the helicopter deck, at right angles to the distribution pipe 5. Distribution pipes 6 branch off from the feed pipe 5, in the illustrated embodiment the centrally located and perpendicularly branched off distribution pipe 6d, but it will be appreciated that the other distribution pipes 6 in principle are branched off in the same way.

The distribution pipes 6 are preferably rectangular sections as indicated in Fig. 2a. Making the distribution pipes 6 in the form of rectangular sections gives good contact with the bottom surface of the grating section 4 for heat convection when the system is supplied with heated water. This gives advantages when de-icing as will be disclosed in more detail below.

Although it is not shown, it is not difficult to envisage that the defining edges of the deck sector, as indicated at 8 in Figure 2, may also be water-carrying distribution pipes with evenly distributed but non-illustrated liquid distribution outlets and having a configuration like the right or left half of the devices according to Figure 2a. The drainage system is indicated in Figure 3 by a gutter 3 parallel to the feed pipe 5, and with a pipe 12 extending from the gutter 3 for carrying water and combustible liquid mixed therewith to a downstream separation step or other further treatment.

The actual landing surface of the helicopter deck is indicated in Figure 3 which shows in section a preferred embodiment of structural sections which are arranged on the liquid distribution pipes 6, parallel to the deck sector base line as indicated by the feed pipe 5.

These pipes may be equipped on their upper side with longitudinal, preferably relatively pointed beads 13, which in order to achieve further increased friction may be broken in the longitudinal direction of the section into relatively short lengths thereby obtaining a certain spiked effect.

With the assembly according to the invention a number of advantages are achieved, of both a traffic safety and a fire safety nature.

In the area of traffic safety, it has previously be necessary on flat decks to use a coating having means embedded therein to give a non-slip surface.

For additional safety, rope work has previously been laid on all kinds of decks in order to attempt to secure better friction in the event of large snow or ice loads.

These precautions can be completely eliminated with the assembly according to the invention.

By means of the thermal effect resulting from water compression downstream of the compression pumps when throttling the water flow that is known from fire fighting technology, it is possible, whenever there is any sign of snow blockage or freezing up of the helicopter deck, to feed hot water through feed pipe 5 and distribution pipes 6 so as to keep the deck free of snow and ice at all times.

Because the grating 4 is directly connected to the distribution pipes 6, which preferably have a rectangular configuration, good heat conduction is ensured, as well as the effective snow and ice clearing resulting therefrom. As mentioned above, the water distribution system is supplied with the aid of a non- illustrated compression pump and a non-illustrated feed line in which there is provided a suitable throttle means, preferably a valve, for thermoregulation.

5 When throttling the water flow from the compression pump, the water will be heated rapidly, which, for example, may represent major problems in ordinary fire hoses. This thermal effect is here intended to be harnessed by an adjustable throttle valve in the feed line to the feed pipe 5 and the distribution pipes 6. When de-icing the helicopter deck, the system can be actuated well before landing and supplied with heated water by means l o of adjustment of the throttle valve. In addition to the hot water between the deck surface and the pipe system helping to clear snow and ice, the large welded surfaces between the distribution pipes 6 and the grating 4 as indicated earlier will be instrumental in conducting heat into the grating, an effect which is enhanced as this is preferably made of aluminium.

15

A further clearing effect arises with the aid of the landing wind from the helicopter as the free rhombus points in the grating sections 4 are turned towards the centre and therefore guide the wind into and under the grating.

20 Substantially improved traffic safety is thereby obtained in addition to pure fire safety

Thus, by means of the system of the invention, major advantages are obtained in that the system under normal conditions can be put into operation in a normal manner without this disrupting the helicopter traffic or disturbing the personnel present, and that the 25 system under abnormal weather conditions with snow and ice can be put into operation using heated water well before landing so that the deck is clear for landing.

The system can be remote-controlled with respect to all the functions including climatic. This is of course done with the aid of suitable temperature sensors, which means that the 30 need for an extra helicopter man is dispensed with on platforms where the crew has been down-sized.

In principle, the system is simple and can without difficulty be incoφorated into existing decks by connection to existing pressurised water systems as, for example, 35 described in NO 176 509-B mentioned above. Owing to the simple structure and ready access to all the components the system is easy to maintain and simple to operate.

For the same reasons, it is also reasonably inexpensive without this having a detrimental effect on safety and efficiency.

Claims

P a t e n t c l a i m s

1.

A safety and fire-extinguishing system assembly on a helicopter deck (1), preferably on offshore installations or ships, of the type which is designed as a polygon divided into a number of sectors (2) and having pressurised water supply for flooding the deck surface in order to remove and, if necessary, extinguish any burning fuel on the deck surface in connection with a possible helicopter accident, and having a gutter (3) running along the periphery of the polygon for receiving flooding water and any fuel it may wash with it, and having a grating system (4) provided at a distance above the deck surface, characterised by a plurality of liquid distribution pipes (6) running towards the centre of the deck from a feed pipe (5) extending along the periphery of the deck, and which vary in length and decrease in number in relation to the decreasing width of the deck sector (2) in question, and with liquid distribution outlets (7) preferably distributed at regular intervals, the liquid distribution pipes (6) being supplied from a compression pump via a feed line having adjustable throttle means incoφorated therein.

2.

The assembly according to claim 1 , characterised in that the liquid distribution pipes (6) are rectangular pipes.

3.

The assembly according to claims 1 and 2, characterised in that the sector bounds (8) are also made in the form of liquid distribution pipes.