DESCRIPTION

The present invention concerns a device for greasing the end of a tube, particularly suitable for being used in the assembly of oil pipelines, pipes for drilling oil wells or other pipes for transporting industrial fluids.

The invention also encompasses the cartridge adapted for containing a greasing substance and configured to allow the sealed coupling with the greasing device of the invention.

As known, pipes of the aforementioned types are made by connecting in series many pieces of tube, each of which has a threaded end that is screwed to the adjacent piece.

There is a need to prevent the fluid flowing in the pipe from leaking through the joints between the various pieces, causing the corrosion of the threads and thus leading to damage to the system and to losses of fluid.

Such a requirement is achieved by greasing the threaded ends of the pieces in advance so that, once screwed in, the grease acts as a sealing element that prevents the fluid from leaking.

The aforementioned greasing also prevents seizure among the pieces of tube during the disassembly of the pipes, which is carried out for example with drilling pipes at the end of use.

According to the prior art, the aforementioned greasing is carried out by a worker, who manually distributes the grease on the ends of each piece.

The aforementioned operation has the drawback that carrying it out in accordance with best practice takes a substantial amount of time, with consequent labour costs.

Moreover, if the operation is not carried out in accordance with best practice, there can be an uneven layer of grease and, therefore, possible local sealing defects of the joint.

The present invention aims to overcome the aforementioned drawbacks.

In particular, the purpose of the present invention is to make a greasing device that allows the grease to be distributed on the end of a tube so as to form a substantially even layer around the tube itself, in particular on the threaded end thereof.

Another purpose of the invention is for the distribution of the grease to be able to be carried out with a particularly quick and simple manoeuvre. The aforementioned purposes are accomplished through a greasing device made in accordance with the main claim.

Further detailed characteristics of the invention are given in the relative dependent claims.

The invention also encompasses the cartridge adapted for containing a greasing substance, in accordance with claim 1 1 .

Advantageously, the even distribution of the grease avoids imperfect joints being obtained between the pieces of tube, thus preventing possible leaks of fluid.

Again advantageously, the speed of execution permitted by the device of the invention limits the labour required and, therefore, the relative costs with respect to what is allowed by the prior art.

The aforementioned purposes and advantages, together with others that will be mentioned hereinafter, will be highlighted during the description of some preferred embodiments of the greasing device of the invention that are given, for indicating and not limiting purposes, with reference to the attached tables of drawings, where:

- figs. 1 a and 1 b respectively show an axonometric view and a side view of the greasing device of the invention;

- fig. 2 shows an axonometric view of the tubular body belonging to the greasing device of the invention;

- fig. 3 shows a sectioned axonometric view of the tubular body of the invention according to a section plane parallel to the longitudinal axis of the same tubular body;

- fig. 4 shows the view from above of the tubular body belonging to the greasing device of the invention;

- fig. 5 shows a side view of the section of the tubular body of the invention according to a section plane parallel to the longitudinal axis of the same tubular body;

- fig. 6 shows a partially sectioned axonometric view of the tubular body of the invention;

- fig. 7 shows a side view of the inlet mouth made on the tubular body of the invention;

- fig. 8 shows a section view of the housing made in the tubular body of the invention to receive the end of a tube; - fig. 9 shows a first reciprocal position between the tubular body and the gun belonging to the greasing device of the invention, such a position being adapted for allowing the loading of a cartridge containing a greasing substance;

- fig. 10 shows the work position taken up by the tubular body with respect to the gun of the greasing device of the invention;

- fig. 1 1 shows a section view of a first embodiment of the cartridge of the invention;

- fig. 12 shows a section view of a second embodiment of the cartridge of the invention.

The greasing device of the invention, wholly indicated in figs. 1 a and 1 b with 1 , is particularly suitable for being used to evenly distribute a greasing substance, in particular grease, on an end of a tube T.

In particular, the aforementioned greasing device 1 is suitable for greasing the threaded ends of the pieces of tube T used to make oil pipelines, pipes for drilling wells or, more generally, in pipes for transporting fluids, in particular corrosive fluids.

The greasing device 1 , according to the invention, comprises a tubular body 2, represented in an isolated manner in figs. 2 to 7, on which an outer surface 3 and an inner surface 4 are defined.

As can be seen in figs. 3 and 5, at the aforementioned inner surface 4 a housing 5 is defined adapted for receiving an end of the tube T, as represented in fig. 8.

In detail, such a housing 5 is defined so that, when the tube T is received in the same housing 5, the inner surface 4 is adapted for facing the outer surface of the aforementioned tube T, as can be seen in fig. 8.

In particular, according to the preferred embodiment of the invention, again represented in figs. 3 and 5, such a housing 5 is defined through the U-shaped profile that the tubular body 2 takes up at its inner surface 4. The advantages of such a type of housing 5 will be made clearer hereinafter.

However, this does not rule out the possibility that for different embodiments of the invention such a housing 5 can be defined in a different way, for example it can be defined by a simple abutment surface arranged at the inner surface 4 of the aforementioned tubular body 2, provided that the same housing 5 allows the coupling, although not stable and permanent, of a tube T with the greasing device 1 of the invention.

The greasing device 1 of the invention, as can be seen in fig. 2, also comprises an inlet mouth 6 made on the aforementioned outer surface 3.

According to the preferred embodiment of the invention described here, the inlet mouth 6 is configured to be sealably coupled with the head of a cartridge containing the aforementioned greasing substance to be deposited externally on an end of the tube T.

In even greater detail, the inlet mouth 6 has, according to a section plane perpendicular to its longitudinal axis X1 , as can be seen in fig. 7, a substantially circular profile. Moreover, as can be seen in fig. 5, at its inner surface 61 , the inlet mouth 6 is equipped, along the direction defined by such a longitudinal axis X1 , with recesses 7 alternating with protrusions 8 to ensure the sealed coupling with the head of the aforementioned cartridge.

Preferably, such recesses 7 and protrusions 8 extend in a spiral, so as to define, advantageously, a threading that allows the sealed coupling by screwing between the same inlet mouth 6 and the head of the cartridge, also equipped with suitable recesses and protrusions extending in a spiral.

According to a variant embodiment of the invention, such recesses 7 and protrusions 8 could not extend in a spiral, but rather could be defined with a "sawtooth" profile, so as to allow the pressure sealed coupling of the inlet mouth 6 with the head of a cartridge in turn provided with suitable recesses and protrusions with "sawtooth" profile.

However, this does not rule out the possibility that in further different embodiments of the invention the inlet mouth 6 does not have the aforementioned circular profile or is not equipped with the aforementioned recesses 7 and protrusions 8 extending in a spiral or not. In other words, it is possible for such an inlet mouth 6 to be configured for the coupling of different devices from a cartridge, provided that the same inlet mouth 6 allows the introduction of the aforementioned greasing substance inside the greasing device 1 of the invention.

Going back to the preferred embodiment of the invention described here, the greasing device 1 comprises, furthermore, a plurality of holes 9 made on its inner surface 4, as can be seen in figs. 2, 3, 5 and 6.

In particular, each of such holes 9 is adapted for facing the outer surface of the tube T when an end of the latter is received in the aforementioned housing 5, as can be seen in fig. 8.

Preferably, but not necessarily, the greasing device 1 of the invention comprises four holes 9, each of which is spaced from the adjacent ones by an angular distance substantially equal to 90°. Moreover, the aforementioned holes 9 are distributed on the inner surface 4 symmetrically with respect to the axis of symmetry defined at the longitudinal axis X1 of the inlet mouth 6.

This does not rule out the possibility that, according to alternative embodiments of the invention, the number of holes 9, made on such an inner surface 4, can be more or less than four; in the minimum case even a single hole 9 could be provided.

Finally, the greasing device 1 of the invention comprises a plurality of ducts 10 defined inside the aforementioned tubular body 2, between the inner surface 4 and the outer surface 3, as can be seen in figs. 3 and 5. Such inner ducts 10 are configured to place the aforementioned inlet mouth 6 in communication with each of the holes 9 so as to allow the insertion of the greasing substance from the same inlet mouth 6 and the flow thereof towards the end of the tube T through the ducts 10 and the holes 9.

Advantageously, the aforementioned characteristics of the greasing device 1 of the invention make it possible to obtain a distribution of the greasing substance on the end of a tube T with a particularly quick and simple manoeuvre. Moreover, the greasing device 1 makes it possible to distribute such greasing substance around such an end of the tube T more evenly with respect to what is obtained with the techniques of the prior art.

A contribution is also made to achieving this advantage by the particular configuration of the aforementioned housing 5. Indeed, with the end of the tube T inserted in the housing 5, since the greasing substance exiting from the holes 9 is directed towards the bottom of such a housing 5, when it touches it, it undergoes a deviation in the lateral direction. In this way, the same greasing substance is distributed evenly also in the spaces of the housing 5 defined between two adjacent holes 9. When the greasing substance has filled the entire gap between the end of the tube T and the inner wall of the housing 5, i.e. when it has touched the entire end of the aforementioned tube T, the same greasing substance in excess tends to come out from the upper part of the greasing device 1 of the invention. Once this situation has been reached, the operator interrupts the flow of the greasing substance towards the tube T and possibly passes on to the greasing of a further tube T.

Preferably, the greasing device 1 of the invention is configured so that the paths defined between the inlet mouth 6 and each of the holes 9, through the aforementioned inner ducts 10, have substantially the same length.

This characteristic, advantageously, makes it possible to make the greasing substance reach the holes 9 with the same pressure. Therefore, the amount of greasing substance that comes out from each of such holes 9 at the same moment is substantially the same. Therefore, thanks to such a characteristic of the greasing device 1 of the invention, an even more homogeneous distribution of the greasing substance around the end of the aforementioned tube T is obtained.

In particular, preferably but not necessarily, as can be seen in fig. 6, the two holes 9 arranged on the same side of the inner surface 4 with respect to the aforementioned axis of symmetry corresponding to the longitudinal axis X1 of the inlet mouth 6 communicate with one another through a duct 101.

Such a duct 101 is, moreover, configured to communicate, substantially at its intermediate area 101a, with a further duct 102 that, in turn, is in communication with the inlet mouth 6. In this case, the particular geometry assumed by the ducts 101 and 102 ensures that the greasing substance travels the same distance to come out from both of the holes 9, therefore achieving the advantages just described.

According to the preferred embodiment of the invention, as can be seen for example in fig. 5, the tubular body 2 comprises a first outer tubular body 21 , in which said inlet mouth 6 is defined, and a second inner tubular body 22, in which the inner surface 4 and the holes 9 are defined.

Such first outer tubular body 21 and second inner tubular body 22 are configured to sealably couple with one another and to internally define the aforementioned inner ducts 10.

Preferably, such two outer and inner bodies 21 , 22 are respectively equipped with an inner and outer threading 211 , 221 so that their coupling is obtained by screwing.

Advantageously, the fact that the tubular body 2 of the greasing device 1 of the invention comprises the aforementioned two outer and inner bodies 21 , 22 makes it possible to adapt the same greasing device 1 to tubes T of different shapes and sizes, by simply replacing only the second inner body 22. Moreover, the fact that the two outer and inner bodies 21 , 22 can be decoupled from one another makes it possible to carry out the cleaning of the aforementioned inner ducts 10 in a quicker and easier manner.

Finally, as can be seen in figs. 1 a and 1 b, the greasing device 1 of the invention preferably also comprises a gun 11 adapted for receiving a cartridge that, in turn, is adapted for containing the aforementioned greasing substance. In particular, the gun 11 is provided with a handgrip 12 at a first end thereof 11a. Such a handgrip 12 allows an operator to activate a thruster 13 adapted for acting in turn on the piston of the same cartridge, therefore forcing the greasing substance to come out from the head of the latter. The gun 11 is also rotatably connected at its second end 11 b with the tubular body 2. In particular, such a rotatable connection is made so that the inlet mouth 6 of the tubular body 2 has its longitudinal axis X1 coinciding with the longitudinal axis X2 of the gun 11 at least for a so-called work position, represented in fig. 10.

Fig. 9, on the other hand, represents a further reciprocal position between the tubular body 2 and the gun 11 that makes it possible to carry out the coupling step of the head of a cartridge with the inlet mouth 6 of the same tubular body 2.

When such coupling is carried out, the tubular body 2, together with the cartridge, is rotated with respect to the gun 11 , so as to reach the aforementioned work position, indeed represented in fig. 10.

Preferably, the gun 11 is equipped with locking means 14 adapted for making the aforementioned work position represented in fig. 10 permanent, unless there is an external intervention by an operator.

Operatively, in order to carry out the greasing of the end of a tube T, a skilled worker positions the aforementioned end in the housing 5, as represented in fig. 8. Thereafter, through the aforementioned handgrip 12 of the gun 11 he/she actuates the piston of the cartridge so as to make the greasing substance flow and evenly distribute it on the end of the same tube T through the inlet mouth 6, the ducts 10 and the holes 9 belonging to the tubular body 2. As stated earlier, the invention also encompasses the cartridge 200, represented in fig. 1 1 and in fig. 12, comprising a hollow cylindrical body 201 in which the greasing substance is adapted for being contained. Such a cartridge 200, as already stated, comprises a head 202, at a first end 201a of the hollow cylindrical body 201 , adapted for allowing the aforementioned greasing substance to come out. Moreover, as already stated, the cartridge 200 comprises a piston 203 operatively coupled at the second end 201 b of the hollow cylindrical body 201 and adapted for pushing the greasing substance so that it comes out through the aforementioned head 202.

According to the invention, the cartridge 200, as can be seen in figs. 1 1 and 12, comprises an insert 204 made of elastomeric material defined around the aforementioned head 202. Such an insert 204 is provided, according to the direction defined by the longitudinal axis X3 of the same head 202, with recesses 205 alternating with protrusions 206 to allow the sealed coupling of the same head 202 with the inlet mouth 6 of the greasing device 1 of the invention, described earlier and in turn provided with recesses 7 alternating with protrusions 8.

In particular, as represented in fig. 1 1 , preferably but not necessarily, such recesses 205 and protrusions 206 extend in a spiral, so as to allow, as already stated, a coupling by screwing with the inner surface 61 of the inlet mouth 6 of the greasing device 1 of the invention, in turn provided with recesses 7 and protrusions 8 extending in a spiral.

According to a variant embodiment of the invention, represented in fig. 12, such recesses 205 and protrusions 206 could not extend in a spiral and rather be defined with a "sawtooth" profile, so as to allow the pressure sealed coupling of the head 202 with the inlet mouth 6 of the greasing device 1 of the invention, in turn provided with recesses 7 and protrusions 8 with "sawtooth" profile.

Preferably, the insert 204 is made on the head 202 by microfusion.

Based on what has been stated, therefore, the greasing device of the invention achieves all of the predetermined purposes.

In particular, the purpose of making a greasing device that allows the grease to be distributed on an end of a tube so as to form a substantially even layer around the tube itself, in particular on the threaded end thereof is achieved. The purpose of making a greasing device that allows the greasing substance to be distributed through a particularly quick and simple manoeuvre is also achieved.