WO1987000223A1 - Pneumatic float- and fender elements for marine use and means for joining such elements together - Google Patents

Abstract

Means for joining together two or several cylindric inflatable buoyant bodies, such as fenders or floats, and the invention relates further to embodiments of buoyant bodies especially adapted for effecting the joints. The invention consists in that the joint is provided by means of a tubular member overlapping the transition zone between each two adjacent fender- or float elements and establishing the interlocking between the said elements by means of the pneumatic pressure in the elements.

Description

PNEVMATIC FLOAT- AND FENDER ELEMENTS FOR MARINE USE AND MEANS FOR JOINING SUCH ELEMENTS TOGETHER.

The present invention relates to a new type of pnevmatic float- and fender elements for marine use, more particularly a means for joining or coupling together two or more such elements together to form a chain or link.

Pnevmatic float- and fender elements for marine purposes are used both individually and in groups, usually in the shape of a link or string of such elements. Such float- and fender work is widely used for various marine purposes, for instance on boats, ships, along piers and in harbours and for other marine purposes such as for oil lenses, paravans and in connection with towing. Pnevmatic floats of this type, usually having regular cylindric form, are also used as inflatable buoyant bodies for smaller vessels, such as salvation floats and the like. The float- or fender elements for such purposes are either provided with a fastening eye or the like in one or both ends or are provided with a through-going channel for a rope, wire, rod or the like, by means of which the elements are linked together.

Known solutions for joining or linking together a number of float- and/or fender elements cause several problems. The main problems arise in the linking- or transition zone between the separate elements in the link. The elements are thus vulnerable for being damaged in the usually recessed transition zone between the separate elements. Further, the transition zone between the elements in a link has a tendency to form a "receiving station" or debris and growth, which in itself causes various problems and are highly undesirable. A special problem arises when such linked together elements are utilized as railing bumper protection along the side of a boat, since the transition zone between each two separate elements in the link forms a source or considerable sea splashing drifting into the boat and being very unpleasant for the personnel aboard. A special disadvantage with a link of float- or fender elements which are joined together with a continuous rope passing through" the elements in the link, is that it may be rather difficult to replace a damaged element in the link. The main object of the present invention is to provide an improved means for joining together two or more pnevmatic float- or fender elements in a way such that the above described disadvantages can be avoided.

A further object of the invention is to provide a new type of pnevmatic float- or fender element which can be joined together in a link in a such way that the separate elements in the link can not undertake pivotable moments relative to each other about the longitudinal axis.

A special object of the invention is to provide a means whereby a link of joined together pnevmatic elements can be extended or shortened in accordance with the need in a very simple and quick fashion.

The present invention is generally characterized in that the pnevmatic float- or fender elements in question are coupled together by means of a tube- or bushinglike member overlapping the transition zone between any two adjacent elements, and in that said bushinglike elements at least partly are being attached by means of the internal pnevmatic pressure in the adjacent buoyant body.

The invention can be realized in several fashions. The bushingshaped member can thus be made in the shape of a separate bushing which is threaded onto an end proportion of each two adjacent elements and being fastened thereto during the inflation of the same. In another embodiment the fender element is at least in one end provided with a tube- shaped, freely existing extension or socket adapted for being threaded onto an adjacent element without such socket or sleeve extension. Thereby a socket connection is formed between the two elements. .The invention can thus be realized with more or less cylindric elements with or without tube- shaped extensions in the respective ends, since the separate elements can be provided with tubeshaped extensions, or by means of separate transition sleeves or sockets.

In order to obtain a dependable interlocking of the elements the socket elements or the end portion of the element without tube extensions are provided with circumferentially arranged, cooperating groove, respectively beads, which smack into mutual engagement when the elements are threaded together, the final interlocking taking place when the elements subsequently are subjected to internal pnevmatic pressure during the inflation thereof. The pnevmatic element will always constitute the internal part in the thereby formed socket joint since the socket-shaped element will remain "free-standing" regardless whether it as a tubeshap^d extension on one of the pnevmatic elements, or is present in the shape of separate sleeve members.

Some embodiments of the invention shall be described with reference to the accompanying drawings, wherein:

Figures la and lb are schematic views showing two conventional embodiments of cylindrical and longitudinal fender elements, respectively, coupled together in a row or link.

Figure 2 is a sectional view through the end part of two adjacent fender elements in accordance with the invention, locked together by means of a special bushing-shaped transition element.

Figures 3a and 3b are detail views in an enlarged scale showing sections of the joining wall between the said two fender elements and which further illustrate the interlocking solution, prior to and subsequent to inflation of the elements, respectively.

Figure 4 is showing a similar view through the end part of two adjacent fender elements in accordance with the invention wherein the one element is provided with a bushing- or socket- shaped extension which is threaded onto a dimensionally conforming end part of an adjacent fender element.

Figure 5 is a sectional view corresponding to Figures 2 and 3 and which illustrates a means consisting of a combined locking- and attachment means between two fender elements.

Figure 6 is a sectional view similar to Figure 5, illustrating two adjacent interlocking elements. A pipe is threaded through the central passage though the elements, said pipe between two adjacent fender elements provided with a laterally extending fastening membey.

Figure 7a is a view illustrating an angularly shaped socalled bow fender provided with a socket extension in each end designed for being joined for instance to a "side fender" as illustrated in Figure 7b.

Figures la and lb are showing two embodiments of conventional float- or fender elements coupled together in a row or link. Fender elements 2,2,2 as shown in Figure la are provided with centrally extended tubeshaped passages 4,4,4. Through these is positioned a pipe or a wire 6. Fender elements of this type are in each end usually provided with a reinforcement collar 8. The fender elements 10 shown in Figure lb are instead of a passage in ecah end provided with a fastening eye 12, 12, etc. and the elements are here joined together by means of rope slings 14 or the like. Fender links of the type shown in Figures la and lb present several dis¬ advantages. Thus, the fendring action will be poor in the transition zones between each pair of elements, and adjacent elements have a tendency to be subjected to tearing in the end parts when exposed to great stresses or loads causing deflation of the fender, either in that for instance the eyes are damaged, or in that the tube elements are damaged in the mouth openings due to stresses caused by the throug-going wire or pipe. As mentioned previously, fender chains or links of this type further give right to growth and also to sea splash. Sea splashing is particularly undesirable, especially when such fender work shall be arranged along the upper side of smaller boats, causing great inconvenience for the persons aboard.

Figure 2 is showing an embodiment for fender elements made in accordance with the invention. Opposing end parts 20,22 of two adjacent fenders 24,24 are herein coupled together by means of a socket or bushing-shaped element 26 dimensioned for being threaded onto preferably recessed end portions 20,22 on the fender element such that the outside of the bushing element extends flush with the outside of the fender elements. When the fender elements are being inflated the bushing will be frictionally locked to the fender elements. In the shown embodiment the fender elements are further provided with a tubeshaped passage 30,30 for receiving a wire 31 or the like. Such fender elements can thus be coupled together by means of a through-going wire as an alternative or in addition to the bushing-shaped transitional elements in accordance with the invention. In addition to providing a double safety measure in regard the intercoupling, such solution can imply other advantages. Thus, the wire can for instance be replaced keeping the fender link intact. A though-going wire will further be of interest if the fender link shall be used as a lens oriboom, such as an oil boom , for towing purposes ©r for other similar purposes. The inside diameter of the bushing- shaped element 26 should be equal to or somewhat larger than the outside diameter of the end portions 20,22 of the fender elements such that the operation of threading the elements together- goes easily prior to that the _.fender elements are being inflated. During the inflation the diameter of the fender element will increase, having into effect that the encompassing bushing-shaped element is being locked to the fender element. Various solutions can be used in order to increase the interlocking strength. This detail shall be further described later.

The detail Figures 3a and 3b are showing enlarged cross- sectional fragmentary views of the transition zone "B", as shown in Figure 4 and illustrates a preferred embodiment of the surface contour on the mutually overlapping fender walls. As shown, the two opposed wall portions facing each other are provided with circumferentially arranged grooves, respectively beads 47,48. The outside diameter of the "tap fender" and the inside diameter of the tubeshaped extension, respectively, are such adapted that a clearance exists there¬ between as shown in Figure 3a prior to that the fender elements are being inflated. The tubeshaped extension is not subjected to internal pressure and will remain with the same diametrical dimension, while the "tap fender" will expand and have into effect that an interlocking of the elements takes place as illustrated in Figure 3b.

Figure 4 is showing an example of the preferred embodiment for a fender element in accordance with the invention. The fender element 40 is in one end provided with a sleeve or bushing-shaped extension 42 which extends flush with a sleeve or bushing-shaped extension 42 which extends flush with the outside of the fender wall proper, while an adjacent complementary fender 41 as shown is provided with a recessed portion 43. The transverse end walls 44 and 45 of the fender elements are in the preferred embodiment for the invention provided with a concave shape as shown before inflation. With a concave end wall is, firstly, hindered a marked swelling of the end walls during the inflation, secondly, one maintains an effective tendering also in the transition zone ,-between two adjacent fender elements, and thirdly, the chances for ripping apart of the fender elements are reduced. In this connection the centrally extending tubeshaped element 46 which extends from end wall to end wall has an important function, since it serves as tension member or tension stay between the end walls and thereby effectively prevents or reduces bulging of same. To serve this function the centrical element obviously does not seem to be pipe- or channel-shaped.

In the embodiment_shown in Figure 5 the end part 51 of the "tap fender" 49 is provided with an imbedded threaded element 50 for an attachment ear 52 which subsequent to the intercoupling of the elements is being threaded into place through flush-going apertures 54 in the tubeshaped extension 56. Several such attachment ears can obviously be arranged if desired. Thus, frequently it is desireable to have two diametrically opposed located attachment ears available for having openings for attachment ears along a fender link. The described solution for attachment ears on the fender link serves at least two functions, namely firstly to provide an extra positive interlocking of the elements, and secondly to provide fastening means along the fender link. In the transition zone between a pipeshaped extension 56 and the fender element 60 proper, can further be arranged small air bleed apertures 59. Such apertures are, however, not required if the fender elements are provided with through-going centrally extending passages as shown in the example.

In Figure 6 is shown an embodiment similar to the one shown in Figure 5. In this embodiment is however through the centrical passage 62 positioned a pipe 64 to which, in the spacing between two fenders, is attached a laterally directed steel wire 66 for attachment of the fender link, for instance along a ship railing or for other purposes. An advantage with this solution is that the fender as such, i.e. the wall material of the fender, is not serving as anchoring for the attachment means.

It shall at this point be remarked that in the Figures showing sections through the end walls of the elements, the said end walls are for the sake of clarity shown in unloaded condition, i.e. without internal pnevmatic pressure.. In inflated condition with normal internal pressure the central passage elements through the fender will be somewhat extended or stretched, and the end walls will attain a contour substantially as shown with stitched lines 61 in Figure 4.

Figure 6a shows an angularly shaped socalled "bow fender" . Such fenders are very applicable to be positioned around the bow on salvation vessels, towing vessels and the like. A such bow fender is being moulded in an angle as shown, such that the total elbow angle or bend corresponds to the bow curvature of the vessel. The shown fender element 70 is in both ends provided with tubeshaped extensions 72 and 74, adapted to be threaded onto complementary side fenders 76 as s-hown in Figure 6b of the rectilinear type having a tap 78 in one end and a tubeshaped extension 80 in the other end.

Float- and fender elements in accordance with the invention can also be made with 180° angle from end to end and thus having substantially semi-circular form such that elements can be coupled together two by two and form a closed ring structure. Such "ring floats" are among other things very actual in connection with offshore activities, such as in connection with the floating- and towing of pipelines. A special advantage with such ringshaped floats is that they can be mounted onto and removed from a pipeline in a quick and simple fashion.

Smaller vessels and boats for leisure and sport and also smaller commercial vessels are usually using separate fenders which are positioned in spaced intervals along the hull to supplement possible fender lists or the like. In recent years, particularly in connection with offshore oil activities, it has been found desirable, however, and in many cases required,to provide towing boats and the like with pnevmatic collars which can give effective fendering, for instance in connection with work at and adjacent to oil rigs, other vessels, etc.

A general shortcoming with linked together fender elements has hitherto been that the transition zone between the separate elements consitutes an undesirable impediment in various ways, such as a reduction of the continuity of the fendring capability of the fender work, and as 'previously mentioned, giving rise to considerable sea splashing whichnot only is an' inconvenience for the persons aboard but also causes accumulation of water in the boat. In order to avoid disadvantages of this kind one has hitherto provided fender elements with more or less plain, cross-going ends, but this solution has not proved to be particularly good, since subsequent to being inflated the end parts will attain a convex curvature. To reduce the problems in connection with the transition zone between the separate fender elements one has also attempted to place fender links in tubeshaped casings or bags, but such implements are expensive and fragile. Through the present invention is provided a solution which removes most of, not to say, all of the problems one hitherto has met in connection with interlinked fender elements. In addition to providing a contiuous fender surface without any practical transition zones between the separate fender elements, one has maintained the possibility to provide attachment means between the elements, either in the shape of fastening ears or the like mounted directly to the fender material, preferably in the overlapping portion between each two of the elements, or as fastening elements attached to a pipe or a wire which is positioned through the centrical passages. When a fender link in accordance with the invention shall be usilized as a boom, such as a socalled oil boom, or in connection with hauling or towing, a rope or wire is placed through the fender link. Special advantages with the invention in connection with such use is that one obtains transverse or radial stability, inasmuch as the separate fender elements cannot rotate relative to each other. Further, the drag function will be very low. .Trials have shown that the interlocking of the elements obtained is very strong and dependable, particularly when the elements are provided with circumferential grooves/beads as illustrated in Figures 3a and 3b. In supplement one may of course, if desirable, use an adhesive on the meeting surfaces.

The separate tube- or bushing-shaped transition elements or alternatively, the tubeshaped extensions on the separate fender elements or floats can be realized in several ways. Thus, one may give the tubeshaped transition elements an extra wall thickness if it is desirable to obtain a special stiffening and/or reinforcement of the joint or the transition zones between the pnevmatic elements. Alternatively it may be desirable for special applications to make the transition zones between the elements especially pliable, for instance for use as floating booms or for application along curved surfaces. Flexibility can be provided in several fashions, for instance by making the tubeshaped transitions with a thinner wall thickness than the elements otherwise, or the tubeshaped elements can alternatively be made with a circumferential fold or bellow which will provide a large degree of pliability of the fender link while retaining torque stability as well as the interlocking strength.

It will be understood that the invention can be realized in a number of different fashions without leaving the scope of invention. The drawings are showing some embodiments of fender elements in accordance with the invention together with auxiliary equipment and where the elements proper are formed as regular cylindrical elements. It shall be understood, however, that the invention can be realized with differently shaped fender elements. The fender elements can thus be either concave or convexly curved in longitudinal direction between the transition zones. Convex-shaped fender elements may for example be actual when fender links in accordance with the invention shall be used as protection along piers and channels or also in connection with towing purposes where a large buoyancy is desirable.

Claims

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

1. Means for joining together two or more inflatable pnevmatic fender- or float elements made of flexible plastics material, c h a r a c t e r i z e d in that the desired number of elements are joined together, one after the other^ by means of a tubeshaped member overlapping the transition zone between adjacent two elements in the row, said overlapping tubeshaped member establishing a continuous joint between the respective fender elements by means of the pnevmatic pressure in the fender elements.

2. Means in accordance with claim 1, wherein said pnevmatic element is integrally moulded with a tubeshaped extension member at least in the one end adapted to be threaded onto and subscribe the end part of an adjacent fender without such tubeshaped extension.

3. Means in accordance with claim 1 or with claim 2, wherein the tubeshaped member constitutes a separate-tubeshaped element adapted to be threaded onto two adjacent pnevmatic fender elements in order to form a continuous transitional joint between the same when said pnevmatic elements have been inflated whereby is effected a binding along the mating surfaces of the tubeshaped elements and the pnevmatic elements, respectivel .

4. Means in accordance with any of preceding claims, c h a r a c t e r i z e d in that the pnevmatic element at least in one of the ends is provided with a recessed cylindrical section adapted for reception of a complementary tubeshaped transitional element whereby is provided a flush transitional joint between the pnevmatic elements.

5. Means in accordance with any of preceding claims, wherein the inside surface of the tubeshaped member or element and the outside of the complementary end section of the pnevmatic element are provided with circumferentially extending grooves, beads or the like, adapted to arrive into mutual mating engagement during the joining aiϊd inflation of the pnevmatic elements and thereby forming a positive interlocking of the respective element contituting the joints. 5. Means in accordance with any of preceding claims, wherein said pnevmatic fender element in per se known fashion is provided with a centraly extending through-going tubeshaped passage for reception of a rope or the like.

6. Means in accordance with any of preceding claims, c h a r a c t e r i z e d in that the end walls on the pnevmati fender elements are concavely shaped relative to the fender body proper, said concavely shaped end walls in each end of the pnevmatic fender element being joined by means of said theough-going tubeshaped passage element.

7. Means in accordance with any of preceding claims, c h a r a c t e r i z e d in that the pnevmatic fender element is angularly shaped between the respective ends, and is given a total bend substantially corresponding to the bow angle of a boat.

8. Means in accordance with any of preceding claims 1 to 8, wherein the pnevmatic fender elements are given a curvature of about 180° such that when two such elements are joined together they form a completed ringshaped buoyant body.

9. Cylindric inflatable pnevmatic buoyant body of flexible plastics material, such as a fender or a float, said buoyant body in one end provided with a tubeshaped open extension having the same diameter as the buoyant body proper, said tubeshaped extension adapted for being threaded onto a complementary cylindric buoyant body without such extension.

10. Cylindric inflatable pnevmatic buoyant body of flexible plastics material, such as a . fender or a float, said buoyant body in both ends provided with a tubeshaped open xtension having the same diameter as the buoyant body proper, said tubeshaped extension adapted for being threaded onto a complementary cylindric buoyant body without such extension.